Energy Management and Home Automation System

1. FIELD OF THE INVENTION

This invention relates generally to energy management and facility automation systems, and more particularly, to such a system having one or more controllers in each home for managing various devices in response to messages from a central controller, which may be programmed by each user to individually and uniquely control each device through a facility controller and which may be further programmed by a utility company to permit load reduction limited to selected devices for short periods of time.

2. DESCRIPTION OF THE PRIOR ART

In recent years, various attempts have been made to provide both energy management systems and home automation systems for controlling various appliances in the home. Such appliances include heating and air conditioning systems, water heaters, lights, various motors and the like. Similar attempts have been extended to commercial facilities, such as offices, stores, ware-houses and factories. Generally, the prior art efforts have been local systems which are expensive on a per facility basis because of the high cost of the main controller. Further, such systems are limited in their applicability and operation, and cannot be readily changed by the user to take into account changing circumstances.

A common problem faced by the utility company is the necessity to reduce demand for electricity, during certain time periods, such as during extremely hot or cold weather, or when an equipment breakdown occurs. Traditionally, the manner by which the utility company has reduced consumption by cutting service to entire neighborhoods or sectors of a grid, thereby totally eliminating all utility loads. In the case of an electric utility company, reducing consumption, when excess demand occurs, can better be accomplished by eliminating or reducing the demand by selected high energy consuming appliances, such as heating and air conditioning units, or water heaters, while leaving the more necessary items, such as lights, and small appliances or equipment, in a home. or business still operating. This type of an approach would greatly reduce the inconvenience to the homeowner and business owner, siLnce life as usual could continue for short times without heat or air conditioning, or unlimited hot water. Moreover, this type of approach has not adequately been addressed in the prior art.

U.S. Pat. No. 4,153,936, issued on May 8, 1979, to William D. Schmitz et al., describes an energy management system for monitoring and controlling energy-consuming loads.

U.S. Pat. No. 4,153,945, issued on May 8, 1979, to Elliol J. Actor et al., describes a control subsystem for controlling sensorbased systems.

U.S. Pat. No. 4,173,754, issued on Nov. 6, 1979, to George E. Feiker, describes a distributed control system in which a function code is sent from a central location to distributed receivers.

U.S. Pat. No. 4,213,182, issued on Jul. 15, 1980, to Charles W. Eichelberger et al., describes an energy load controller that sets various energy loads to various predetermined levels. The controller responds to information provided by a user-input device.

U.S. Pat. No. 4,217,646, issued on Aug. 12, 1980, to Anthony V. Caltagirone et al., describes an automatic control system for a building. The system of this patent sends control signals to devices in various regions of a building.

U.S. Pat. No. 4,375,637, issued on Mar. 1, 1983, to Paul A. Desjardins, describes an integrated alarm, communication, and building management system.

U.S. Pat. No. 4,530,008, issued on Jul. 16, 1985, to David S. McVoy, describes a secured communications system that prevents unauthorized access.

U.S. Pat. No. 4,567,557, issued on Jan. 28, 1986, to Martin J. Bruns, describes a building intelligence system with an uninterruptible power supply.

U.S. Pat. No. 5,119,412, issued on Jun. 2, 1992, to Arnaldo Attallah, describes a system for regulating and monitoring devices by telephone.

None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.

In accordance with one aspect of the invention, there is provided a utility commodity load reduction system including a plurality of controller means, each located within a different one of a plurality of facilities, for controlling the operation of various utility commodity consuming devices within the one facility. The system further includes central command means for providing general commands to each of the controllers the manner in which that controller controls the operation of the devices within each facility and utility command means for causing selected utility commands to be provided to selected ones of the controllers for causing selected ones of the devices being controlled by the selected controllers to operate in a manner consuming less of the utility commodity.

One preferred embodiment of the subject invention is hereafter described with specific reference being made to the following Figures, in which:

FIG. 1 shows a generalized block diagram of the energy management and me automation system of the subject invention.

FIG. 2 shows a block diagram of the water heater and automation control unit and the HVAC control unit used in user facility portion f the system shown in FIG. 1.

FIG. 3A shows a more detailed block diagram of the scheduler/controllers of the water heater and automation control unit shown in FIG. 2.

FIG. 3B shows a more detailed block diagram of the scheduler/contr lers of the HVAC control unit shown in FIG. 2.

FIG. 4 shows the programmable thermostat used with the HVAC controller of e subject invention.

FIG. 5 illustrates the general format of a paging message sent from the customer command center computer to a pager receiver in a control unit.

FIG. 6, having diagrams A, B and C, illustrates the makeup of the Schedule Information message sent from the customer command center computet to a pager receiver in a control unit.

FIG. 7, having diagrams A and B, illustrates the makeup of the Time, Date and Daylight message sent from the customer command center computer to a pager receiver in a control unit.

FIG. 8 illustrates the makeup of the Weather Information message sent from the customer command center computer to a pager receiver in a control unit.

FIG. 9 illustrates the makeup of the Initialization message sent from the customer command center computer to a pager receiver in a control unit.

FIG. 10 illustrates the makeup of the Utility Company Setup message sent from the utility command center computer to a pagier receiver in a control unit.

FIG. 11 illustrates the makeup of the Utility Company Initialization message sent from the customer command center conputer to a pager receiver in a control unit.

FIG. 12 illustrates the makeup of the User Override message sent from the customer command center computer to a pager receiver in a control unit.

FIGS. 13A and 13B, having diagrams A, B, C, D, E and F, illustrates the makeup of the System Parameter message sent from the customer command center computer to a pager receiver in a control unit.

FIG. 14 illustrates the makeup of the Expanded message sent from the customer command center computer to a pager receiver in a control unit.

FIGS. 15A and 15B are examples of types of published schedule used by a user of the invention for programming the HVAC unit or water hester units to be controlled; and

FIG. 16 is a general flow diagram useful in understanding, the operation of the program controlling the microprocessors used in the control units.

Referring to FIG. 1, a block diagram of the energy management and automation system 10 of the subject invention is shown. System 10 is organized to control both the usage of energy and the convenience of using electrical energy consuming devices in a wide area of facilities 12, such as homes, commercial buildings, apartment units and the like. One or more controllers 4 in etch facility 12 provides electrical control signals to various electrical consuming devices 16, such as heating and cooling units, water heaters, lights of various types, pumps, electrical appliances such as coffee makers or toasters, home entertainment devices, such as televisions, stereos, video recorders, and the like. The signals provided from controller 14 to devices 16 are of a type which may either turn the appliance on or off, or may set the devices 16 to an intermediate value, such as setting dimmable lights to a forty percent value.

Some devices, such as heating, ventilating, and air conditioning units (HVAC), water heaters, lights and the like, will require additional controls, such as thermostats or switches to control whether the appliance is to be turned on. Thus, in some instances, the "on" signals from controller 14 merely permit the appliance to turn on if other conditions are present. For example, the water heater control "on" signal permits more hot water to be generated, but the thermostat associated with the water heater must still indicate that hot water is needed. On the other hand, the "off" signal prevents the appliance from being on, regardless of the setting of other controls associated with the appliance.

The central, or common, portion 18 of system 10 includes a transmitter 20 which sends various signals to the controllers 14. These signals may address an individual controller 14, a group of controllers 14 or all of the controllers 14. While any communication link may be used from transmitter 20 to controllers 14, the preferred embodiment described herein utilizes the paging network services offered by various telephone companies and independent providers. Other communications links, such as, ISDN, television cable, FM radio, telephone lines, or direct communications may alternatively be used. The contents of the paging messages, indicated by the notation PAGE in FIG. 1, transmitted by transmitter 20 are determined by a customer command center computer 22 and a utility command center computer 24. It should be noted that there may be several utility command center computers 24 attached to transmitter 20 and computer 22, although only one is shown in FIG. 1. Computers 22 and 24 may be coupled to transmitter 20 by conventional telephone lines, which may be dedicated lines, or shared lines used in the public network, and provide appropriate signals to transmitter 20 to permit the subsequent transmission of paging message packets manifesting the appropriate information, as described hereafter with respect to FIGS. 5 through 14. In addition, computer 22 can communicate with the various controllers 14 over the public telephone network, as indicated by the line label TEL.

Generally, the particular manner by which the various devices 16 are to be controlled is determined by programmed command data stored in each of the controllers 14 in conjunction with a preexisting program contained in each controller 14. The programmed data is normally generated by customer command center computer :22 and transmitted to controllers 14 as paging message signals by transmitter 20, although in some instances it may be locally generated by operation of, for example, certain key sequences on a thermostat. Many of the paging message signals sent to controllers 14 are determined by the manner in which a user programs computer 22, using a conventional DTMF tone or pulse dial telephone communicating with computer 22. Some paging message signals, however, are determined solely by the customer command center computer 22 itself and automatically sent to all control units 14. The various paging message signals and the manner in which the user programming occurs is hereafter described in more detail.

In certain instances, the energy management and automation functions programmed by the user may be overridden by the utility company when it is necessary to reduce the consumption in a particular area. In this situation, utility command center computer 24 provides signals to transmitter 20, which, in turn, provides appropriate paging messages to the various controllers 14. These messages may cause certain appliances, such as heating or cooling units or water heaters, to be turned off, for selected times, such as for fifteen minutes, or for alternate ten minute increments over a defined period. Alternatively, the paging messages generated at the utility command center computer 24 may only require the selective disabling of certain appliances, such as reducing the temperature at which a heating unit can turn on, or increasing the temperature at which a cooling unit can turn on. The utility company paging messages are only sent to those facilities who have agreed to participate in a reduction program, usually in exchange for a reduced cost for electric power, natural gas or other commodity supplied. Other utility companies, such as gas utilities or water utilities, may also participate in the utility commodity reduction ability afforded by system 10. Computer programs within controllers 14 recognize the utility company paging messages and prevent a user from overriding the commands to reduce energy consumption, using the keys 84 on thermostat 42 or overriding the powerline transceiver 54 controls, something which the user can otherwise do. However, upon request to the customer command center 22, a utility company can authorize energy consumption in an emergency situation, such as a medical necessity.

Each message generated by transmitter 20 may be a typical paging message. For example, the paging message may be a numeric paging message consisting of twenty-three characters, each of which may be the numeric values "0"-"9", or the paging message may be an alpha/numeric paging message consisting of 80 characters, each of which may contain many more than the ten values available with the numeric paging message. In all of the paging messages, the first digit of the paging message defines the type of signal and the last digit is a checksum,digit. The various types of signals generated by computers 22 and 24, and transmitted as paging messages by transmitter 20, may be generally classified as containing, Schedule Information, Time, Date and Daylight Information, Weather information, Initialization information, Utility Company Set,up information, Utility Company Activation commands, User Override commands, and System Parameter commands. Generally, these paging messages are designed for transmittal as a twenty-three digrit numeric paging message, with the first digit identifying the type of signal. However, if the first digit of a paging message is, a "9" (or alternatively any number other than those between "0" alnd "8"), it may be used to identify another paging format, such as the 80 character alpha/ numeric format. Each of these messages and the response by controllers 14 thereto will be discussed in more detail hereafter.

Referring now to FIG. 2, a generalized block diagram of the controller unit 14 within a single facility 12 is shown. Controller 14 consists of one or more of two different types of control units, which are a HVAC (Heating, Ventilation and Air Conditioning) control unit 26 and a water heater and automation control unit 28. The HVAC control unit 26 is dedicated to controlling the heating and cooling of the home, whereas the water heater and automation control unit 28 controls the water heater and up to sixteen other appliances. It should be noted that within any given facility, one or more of either type of control unit 26 or 28 may be utilized, or alternatively, either unit 26 or 28 may be eliminated, if no desire exists for that particular unit. However, for most facilities, at least one of each type of control unit 26 and 28 will be used.

The primary portion of the HVAC control unit 26 is a scheduler/controller 30, which has a pager receiver 32, an HNAC controller 34 and a telephone interface (TI) 36 connected thereto. Pager receiver 32 may be any commercially available module capable of receiving and decoding the telephone company pager messages, such as the Model BPR2000 pager receiver, manufactured by Motorola, Inc. of Boynton Beach, Fla. Pager receiver 32 detects all pager messages broadcast and responds to certain message signals by providing a series of signals to scheduler/controller 30 manifesting a sequence of the digits zero through nine. In conventional digital pager systems, used by individuals, the digits received by the pager receiver 32 are displayed on a conventional seven segment liquid crystal display. In control unit. 26, the pager receiver 32 signals used to illuminate the seven segment display are intercepted and provided to scheduler/controller 30, where they are decoded to manifest the digits they represent. This permits the use of commercially available pager receiver modules for pager receiver 32.

Telephone interface 36 may similarly be any conventional DTMF receiver/transmitter circuit which detects, decodes and provides digital signals to controller 30 in response to conventional DTMF tone signals provided over the public access telephone network. HVAC controller 34 may be a commercially available programmable HVAC electronic thermostat, such as the one manufactured by Alerlton TechnologieS, Inc., of Seattle, Wash., under Model Number SATUX. While the hardware of HVAC controller 34 may be commercially available, the computer program, or firmware, of the commercial version require S modification to provide the information required by control unit 26, as will be more fully explained hereafter. Generally, HVAC controller 34 provides output voltages to control the fan and heating and cooling units of conventional heating and cooling units 38 found in most types of facilities 12. A series of switches 40 are set to indicate the particular type of heating/cooling unit 38 present in the facility 12. In addition, HVAC controller 34 is connected to a programmable thermostat 412, which may be controlled by the user to affect the operation of the heating/cooling unit 38. Thermostat 42, which is shown and described in more detail in FIG. 4, is simply a temperature detector, keyboard and display in a single package.

The water heater and automation control unit 28 is similar to the HVAC control unit 26. It also includes a scheduler/ controller 44 which is connected to a pager receiver 46 and telephone interface 48. Pager receiver 46 is identical to pager receiver 32 and telephone interface 48 is identical to telephone interface 36, both described above. In addition, scheduler/controller 44 hats a relay and driver circuit 50 coupled thereto, which switchably permits power to be applied to a conventional water heater 52, or other high amperage device, such as pumps of various types. Relay and driver circuit 50 may be simply a 35 amp switchable relay connected as a switch in series with the power lines connected to water heater 52. In addition, a transceiver 54 is connected to scheduler/controller 44 and may control up to N different appliances connected thereto.

One type of transceiver 54 which may be used is a standard power transceiver operating under the X-10 standard of providing RF signals over the electric lines existing throughout the facility 12. Such a device may control up to sixteen different energy consuming devices 56 connected thereto with commercially available interface devices. An example of transceiver 54 which may be used is a model TW523 manufactured and sold by X-10 USA of Northvale, N.J. Other types of connections, such as twisted pair, coaxial cable, fiber optics and so forth may also be utilized to interconnect scheduler/handler 44 with the various devices being controlled. Some of these connections may be bi-directional to permit communication of data back to scheduler/controller 44.

As noted above, telephone interfaces 36 and 48 permit communications between the command center computers 22 and 24 alnd each control unit 26 and 28 by using the public telephone network. To better use this telephone communication ability, an auto-dialing device may be included in each control unit 26 and 28. With this additional hardware, each control unit 26 and 28 may be directed to perform certain tasks and report the results to a designated telephone number. Where many units are to perform the same taLsk and report the results, the paging signals maybe used to address many units at one time and then each can call the designated number until a report is made. of course, this may require many automatic re-dial attempts until all units successfully report. An example of such communication is that system 10 may be include various devices 56 arranged to read utility meters, such as water, electric or gas meters, and report the reading back to the particular utiliLty company. The utility company may broadcast a broad based paging message requesting each control unit 26 or 28 in a designated area to read the meter and report the results to a designated utility company telephone number. Similarly, such action may be programmed to occur at specified times and dates by using the paging messages described herein. Alternatively, system 10 may be designed or programmed by appropriate paging messages to require each control unit 26 or 28 to report its status back to command center 22 or 24, either automatically, or on command.

Referring now to FIG. 3A, a block diagram of scheduler/controller 44 in water heater and automation controller unit 28 is shown. From a hardware view, scheduler/controller 44 is a microcomputer system, having, as its primary controller, a microprocessor 58, such as a commercially available Z-80 type microprocessor. Microprocessor 58 includes a sixteen bit address bus AB and an eight bit data bus DB, which are applied to various other modules in scheduler/controller 44, as hereafter explained. In addition, microprocessor 58 includes a plurality of various control signals for controlling the operation of various other modules. These control signals include the MREQ and M1 signals for controlling memory and I/O (input/output) access, the WR and RD signals for controlling the writing and reading of data to and from modules selected by the MREQ and M1 signals, the INT and NMI interrupt signals which interrupt the operation of microprocessor 58, the RESET signal which resets microprocessor 58 upon the application of power thereto, and the CLK signal which controls the frequency of operation of microprocessor 58. Each of these control signals are well known in the literature explaining the operation of a Z-80 microprocessor.

Conventional RAM memory 60 and EPROM memory 62 are coupled to bits 0-14 of address bus AB, to bits 0-7 of data bus DB and to the RD control signal from microprocessor 58. While not shown, AM memory 60 may have a voltage backup system, such as a large capacitor or a battery, to prevent the loss of data in the event of a power failure. In addition, a memory select circuit 64 is provided to select one of RAM memory 60 or EPROM memory 62 in response to the MREQ signal and A15 address bus signal applied thereto. The selected one of RAM 60 or EPROM 62 then.responds appropriately to the then occurring memory operation instruction from microprocessor 58. RAM 60 is addressed by the address lines A0-A12, and Address lines A13 and A14 are used as chip select alnd write enable signals. EPROM 62 is addressed by address lines PLOA14, and thus, may be a 32 K byte memory.

Scheduler/controller 44 also has a clock circuit 66 which provides various signals to the CLK, RESET and NMI inputs of microprocessor 58. Clock circuit 66 includes a conventional crystal oscillator circuit, the output of which is provided as the CLK input to set the timing of microprocessor 58. The oscillator signal is also divided and synchronize with a SYNC signal from transceiver 54 to provide an interrupt Signal at multiple as of 8.33 milliseconds to the NMI input of microprocessor 58. In addition, the PWRON signal from the power supply 68 is provided as an indication that power has been applied and is Synchronized with the oscillator signal to provide a Signal to the RESET input to reset microprocessor 58. Power supply 68 also provides the +V and -V voltages used throughout the circuit of controller/scheduler 44.

In addition, scheduler/controller 44 has two I/O ports 70 and 72 and a DTMF port 74, each of which are enabled by an I/O select circuit 76. Select circuit 76 has the Al and A2 address bus signals, the RD, WR and M1 signals applied thereto. The WR and M1 signals enable I/O select circuit 76 to decode the Al, A2 and RD signals applied thereto and provide one of the RD1, RD2 and WRI signals, which respectively enable I/O port 70, DTMF port 74 and I/O port 72. Generally, each of the ports 70 and 72 are used to permit microprocessor 58 to communicate with the various other modules in water heater and automation unit 28, that is transceiver 54, pager receiver 46, telephone interface 48 and relay and driver 50. Transceiver 54 provides a Receive (REC) signal and a Synchronization (SYNC) signal to scheduler/controller 44 and receives a Transmit (XMIT) signal-from scheduler/controller 44. The SYNC signal is a 120 hertz signal manifesting the zero cross point of the normal power line signal and the REC and XMIT signals are serial data and control signals between transceiver 54 and scheduler/controller 44. Pager receiver 46 similarly provides a CLOCK signal and a data signal and responds to a READ signal provided thereto. Telephone interface circuit 48 provides a RING signal and a DTMF signal and responds to a TONE signal and a SEIZE signal in a conventional manner. Finally, the relay and driver circuit 50 responds to a RELAY signal which causes the relay therein to be open or closed, depending upon the value of the REIAY signal.

I/O port 70 is used to receive incoming signals and is selected by the RD1 signal from I/O select circuit 76 and, when selected, receives ,the last data values applied at the eight input ports, labeled "0" through "7", thereof and provides it to data bus DB. The "0" input is connected to receive the RING signal from telephone interface 48 and the "1" input is not connected. The "2" input of I/O port 70 is connected to ground through a push button switch 78 and the "3" and "4" inputs to I/O port 70 are connected to two poles of a three pole switch 80 respectively. Three pole switch 80 has its switching arm coupled to ground and the third pole thereof is left unconnected. The owner or installer may use the two switches 78 and 80 to clear the RAM memory 60 prior to initialization. The 5 input of I/O port 70 is connected to receive the STD data signal from DTMF port 74, which indicates that data is ready to be sent on lines 0-3 of the data bus containing data received by telephone interface 48. DTMF port 74 is enabled by the RD2 signal form I/O select 76, and when the RD2 signal is received thereby, DTMF port 74 actually provides the binary data it has detected and decoded from the DTMF tones applied thereto from telephone interface 48. DTMF port may be any commercially available module, such as the MT8870 available from Mitel, Inc.

The "6" input of I/O port 70 is connected to receive the RTEC signal from transceiver 54, and represents one bit of data provided from one of the units 56 attached to transceiver 54. This data is provided in conjunction with the SYNC signal from transceiver 54, which is applied to clock circuit 66 and causes an interrupt signal to be provided to the NMI interrupt of microprocessor 58. WhLen this occurs, the REC data is read by the microprocessor 58 by enabling I/O port 70.

The "7" input of I/O port 70 is connected to receive the DATA signal from a shift register 82. Shift register 82 operates in conjunction with pager receiver 46 and receives the PDATA signal and the CLOCK signal from pager receiver 46. The CLOCK signal also is applied to the INT maskable interrupt input of microprocessor 58 to cause an interrupt thereof whenever pager receiver 46 receives and has processed data.

Where pager receiver 46 is a commercially available twentythree character digital receiver, it typically includes a twelve digit, seven segment display. The twenty-three digits are displayed in two groups of eleven and twelve digits each, with the twelfth digit of the first panel being a special character in the shape of a small "c" to indicate that there is a continuation of the message. In other receiver systems, the first panel includes twelve digits, with the last digit blinking as an indication that there is a continuation of the message. In both systems, they remain in the second panel. Scheduler/controller 44 captures the signals provided to the display by pager receiver 46 and then decodes the seven segment encoding to determine the digit, which is then converted to a binary code and stored in RAM memory 60.

Pager receiver 46 operates by causing the message to be displayed by issuing a serial PDATA signal of ninety-two bits and a CLOCK signal each time a bit of the PDATA signal occurs. As noted above, the CLOCK signal is applied to the INT input of microprocessor 58. Upon receiving the first interrupt, the program associated with microprocessor 58 disables the INT input for a period of time sufficient for all of the bits in the PDATA signal from pager receiver 46 to be entered into shift register 82. During this time, each bit of the PDATA signal is entered into the lowest register of shift register 82 by each CLOCK signal, with the remaining bits being shifted one stage higher. For a Motorola Model BPR2000 pager receiver, the digital data is detected and applied as a ninety-two bit serial signals manifesting a twelve digit seven segment display. Within the ninety-two bits, four bits are for special control characters and four bits are not used, leaving eighty-four bits to manifest twelve seven segment digits. It is this serial signal within the pager receiver 46 that is intercepted and applied as the PDATA signal to shift register 82.

I/O port 72 is used to provide signals to the various other modules in scheduler/controller 44. I/O port 72 receives the data to provide from data bus DB and is selected by the WRl signal from I/O select 76. I/O port has eight output ports, labeled 0-7. Port "0" provides the READ signal to pager receiver 46, causing it to provide the second message panel of eleven or twelve characters to shift register 82. The READ signal is the electronic equivalent of depressing the Read button on a conventional pager, theriby allowing display of another message, or the remainder of a message. Port "1" is coupled to a light emitting diode (LED) 84, which is used to signal the user or serviceman of various status conditions of controller/scheduler 44.

Ports "12" and "13" of I/O port 72 provide the TONE and SEIEZE signals to telephone interface 48 as a part of processing telephone communication between controller/scheduler 44 and the customer command center 22. Similarly, port "14" provides the XMIT data to transceiver 54 to cause the execution of commands by the, various appliances 56 connected to transceiver 54. For example, an )AIIT signal may be a series of bits causing a coffee pot to turn on, ora light to turn off. Port "5" provides the RELAY signal to set or reset the relay driver 50, typically for controlling a water heater. Port "16" is not connected.

Port 1171 of I/O port 72 is the SRCLK signal, which is connected to form a logical OR with the CLOCK signal at the clock input of shift register 82. As explained above, the CLOCK signal clocks the PDATA bits from pager receiver 46. Once the data manifesting the first panel of the message is completely provided to shift register 82, it is transferred as the DATA signal to microprocessor 58 and decoded into the various digits it represents. This transfer occurs by the provision of an appropriate number of SRCLK signals from I/O port 72 under the control of microprocessor 58. The number of SRCLK pulses will depend upon the number of stages in shift register 82, as it is first necessary to move the ninety-two bits originally stored in stages zero to ninety-one to the end stages of shift register 82 before commencing the actual transfer of data. After all ninety-two bits are transferred to microprocessor 58, the READ signal is issued from port 0 of I/O port 72 and the second panel of signals is stored in shift register 82 and transferred to microprocessor 58 as just explained.

Referring now to FIG. 3B, scheduler/controller 30 used with the HVAC control unit 34 is shown. Scheduler/controller 30 is essentially the same as scheduler/controller 44 shown in FIG. 3A and like number labels are used to represent like components. The differences between the two scheduler/controllers 30 and 44 is that scheduler/controller 30 controls the HVAC controller 34, which, in turn, controls the heating/cooling unit 38 and responds to information and commands from thermostat 42, instead of the transceiver 54 and relay and driver circuit 50 in scheduler/controller 30. HVAC controller 34 responds to data of the EMIT signal from pin 4 of I/O port 72 and provides the REC signal to both port "6" of I/O controller 70. In addition, the REC signal from HVAC controller 34 is provided to clock circuit 66, along with an EN signal from port "5" of I/O port 72. The REC and EN signals are used to generate the non-maskable interrupt, NMI, signal at a rate of 0.833 msec, which is at least ten times as fast as the NMI signal provided in FIG. 3A. Referring now to FIG. 4, the programmable thermostat 42 used with the HVAC controller 34, is shown. Basically, thermostat 42 is a simple keyboard and display device with an internal temperature sensor. It is connected directly to HVAC controller 34 and is used to permit the user to set various parameters stored in memory associated with HVAC controller 34 for controlling the temperature and other operating conditions of the,heating and cooling unit 38. As previously described, HVAC controller 34 includes its own microprocessor and a communication channel to permit microprocessor 58 in scheduler/controller 30 in FIG. 3B to read the user set parameters, as well as data internally generated by HVAC controller 34, and to provide various other commands and data values to HVAC controller 34. Thermostat 42 has seven keys 84, respectively labeled WARMER, COOLER, ON, OFF, HOME, AWAY AND SLEEP and a two digit display 86 which normally displays two numeric digits manifesting the sensed temperature. Display 86 is also capable of displaying letters of the alphabet to indicate the present mode of operation. For residences, the various user modes are HOME, AWAY, SLEEP, ON AND OFF, but for other facilities, such as commercial buildings, the modes are OCCUPIED, UNOCCUPIED, MAINTENANCE, ON and OFF. Thus, a commercial building thermostat similar to thermostat 42 would have the various keys labeled as WARMER, COOLER, ON, OFF, OCCUPIED, UNOCCUPIED and MAINTENANCE. In addition, there is also a SERVICE mode available for both residences and other facilities and is only to be used by the installer or repairman. Thermostat 42 is electrically coupled to the HVAC controller 34, as seen in FIG. 2, and is one of the manners in which the heating, air conditioning and ventilation system of the facility can be controlled by the user. For a home, at any given time, the heating, ventilation and air conditioning management is set based upon whether the user is home, away or sleeping; hence, the HOME, AWAY AND SLEEP modes. The primary parameter of control are a series of set-point temperatures, which are set by the user to determine operation during the various HOME, AWAY and SLEEP modes. Generally, during the HOME mode, the home is maintained cooler if air conditioning is required and warmer if heating is required. During the AWAY mode, the home is maintained warmer if air conditioning is required and. cooler if heating is required and during the SLEEP mode, the home is maintained at temperatures between the HOME and AWAY modes. During the ON mode, the HOME mode temperatures are used and, in effect, the ON mode merely overrides the AWAY or SLEEP modes to function as in the HOME mode. During the OFF mode, even lower heating and higher cooling set-points than used in the AWAY mode. may be utilized. For example, the OFF mode may be used during a vacation where an extended time away from the home is anticipated.

To program HVAC control unit 34, the various keys 84 on thermostat 42 are pressed. When the WARMER key 84 is pressed during normal operation, that is when display 86 is displaying the current temperature, display 86 displays the current mode (HO feor HOME, SL for SLEEP and AY for AWAY). On the other hand, if display 86 is displaying a set-point temperature (as a result of the user having previously pressed the HOME, AWAY or SLEEP keys 84, as discussed below), then pressing the WARMER key 84 increments the displayed set-point temperature. Pressing the COOLER key 84 when the current temperature is displayed on display 86 has no effect. However, if a set-point temperature is being displayed on dispLay 86, then the set-point temperature, as displayed, is decremented by pressing the COOLER key 84.

The ON and OFF keys 84 are used to override the previously set HOME, SLEEP and AWAY modes. This is done by controller timers contained in the software of scheduler/controller 34. Specifically, when ON key 84 is pressed, an ON timer is incremented in 0.1 hour increments (six minutes) up to a maximum of 9.9 hours. When the ON timer is set to 9.9, it does not decrement and thus is permanently set. During the time the ON timer is non-zero, the system is forced to the HOME mode, regardless of the times previously programmed for the various modes. When the OFF key 84 is pressed, the OFF timer is incremented in 0.1 hour increments to a maximum of 9.9. At a setting of 9.9 the OFF timer is not incremented, Tut when displaying any other value, it is decremented in real time back to zero. As long as the OFF timer is non-zero, the OFF set-points are used in controlling the temperature by heating or cooling. A depression of either the ON or OFF keys 84, or any of the HOME, SLEEP or AWAY mode keys 84, when either of the ON or OFF timers have values remaining cancels the remaining ON or OFF time. The ON and OFF keys 84 may also be used with the mode (HOME, SLEEP or AWAY) keys 84 to control the fan operation of the HVAC unit 38 when operating in that mode. Specifically, if a mode key 84 is pressed and the ON key 84 is pressed within two seconds thereafter, the fan is set to operate for that mode in a continuous manner and if the OFF key 84 is pressed within two seconds of pressing a mode key 84, the fan is set to operate in that mode in an intermittent manner, which is similar to the "automatic" setting of a conventional thermostat, that is, the fan only operates while or shortly after heating or cooling is occurring.

Each of the HOME, AWAY and SLEEP keys 84 are used to display the heating and cooling set-points used in the various modes. As used herein, the set-point is the temperature at which heating or cooling occurs. Thus, when the temperature in the facility falls to the heating set-point, the heating unit is turned on and when the temperature in the facility rises to the cooling set-point, the cooling unit is turned on. Generally, the first time one of HOME, AWAY and SLEEP keys 84 is pressed, the heating set-point temperature is displayed for five seconds. If the same key 84 is pressed a second time while the heating set-point temperature is being displayed, the cooling set-point temperature is displayed Ior five seconds. Each displayed set-point temperature may be increased or decreased using the WARMER or COOLER keys 84 during the five seconds the set-point temperature being displayed, as described above.

If either of the HOME, AWAY or SLEEP keys 84 are held depressed for one half of a second, the time scheduler commands are overridden and that mode is entered. This new mode then remains until the scheduler senses the time for a programmed mode change.

When in any of the HOME, AWAY or SLEEP modes, the fan may be set to operate either continuously, or intermittently with a thirty second overrun. It should be noted that the system is designed to prevent. either heating or cooling unless the fan is on. In the HOME MODE, the building is heated to the home heating set-point temperature and cooled to the home cooling set-point temperature. The maximum home heating set-point temperature the user is normally permitted to select is 80.degree. F. and the minimum home cooling set-point temperature the user can select is 70.degree. F., although both of these home set-point temperatures are adjustable in the SERVICE mode.

The maximum heating and minimum cooling set-point temperatures the user can select in the AWAY mode are 65.degree. F. and 74.degree. F. respectively, although these temperatures may be changed in the SERVICE MODE.

The maximum heating and minimum cooling set-points temperatures that the user can select in the SLEEP mode are 76.degree. F. and 74.degree. F., respectively, and again, these temperatures may be changed in the SERVICE mode.

In each of the HOME, SLEEP and AWAY modes, the heating and cooling set-point temperatures cannot be set within two degrees of one another. If an attempt is made to adjust one of the set-point temperatures to within two degrees of its opposite counterpart, the counterpart is automatically moved two degrees away.

The final mode is the SERVICE mode, which is normally only entered by a serviceman entering a prescribed sequence of key 84 depressions. For example, the sequence to enter the service mode may be COOLER, COOLER, HOME, ON and SLEEP, in that order. During the SERVICE mode, the system variables, such as the maximum or minimum set-point temperatures in the various normal modes may be viewed, or, if desired, changed. Each of the various system parameters has a two letter code, which may displayed along with the setting, by pressing the HOME and AWAY keys 84. Once the value for a parameter is displayed, it then may be adjusted upward or downward by respectively pressing the WARMER or COOLER keys 34.

The various parameters and the initial setting for each parameter are given in table I below:

The HVAC code refers to the manner in which switches 40 shown in FIG. 2, are set. The particular setting of the various switches 40, which are included in HVAC controller 34 to designate the type of HVAC unit being controlled. These switches are normally set during installation and need not be reset until the actual heating/cooling unit 38 is replaced or modified. Thus, no provision is provided to modify these switches in the SERVICE mode.

Generally, switch number "7" is set to manifest the presence of either an air conditioning (AC) unit or a heat pump (HP) unit, switches "9" and "10" are set to designate the number of cooling stages in an air conditioning system or the number of compressors in a heat pump and switches "11" and "12" are set to designate the number of heating stages in an air conditioning system and the number of auxiliary heat strips.

The various set-points can be adjusted, as explained above, by pressing the WARMER or COOLER keys 84 as the particular code and programmed temperature is displayed. The system is programmed so that the maximum set-point temperature can never exceed 80.degree. F nor can the minimum set-point temperatures be below 45.degree. F. The button counter variable is the time, in 0.1 second increments, that the HOME, AWAY and SLEEP keys 84 must be held down in order to cause a switch to the selected mode. This time is initially set to 0.5 seconds, but may be varied by the user or the service-person in the SERVICE mode.

The heating and cooling ramp time parameters are ramp cycle times in minutes and are used to control the heating and cooling cycles. Heating or cooling commands calling for heating or cooling functions may only be executed at the beginning of a ramp cycle, but the heating or cooling may be turned off at any time during a ramp cycle. The heating and cooling ramp percent parameters are determined as the current value, as a percent of the respective ramp times divided by the time between ramp signals. These values may be reset in the SERVICE mode using the WARMER and COOLER keys 84. The heating and cooling control signals which are internally generated in the HVAC controller using a modified proportional integral derivative algorithm and are used to drive the heating or cooling units.

The condensate alarm goes off when too much water is in the condensate pan and may be varied to either turn off cooling only (displays "C") or turn off the fan, heating and cooling units (displays "A").

Referring again to FIG. 3B, all of the data discusse d above is maintained in a memory associated with the microprocessor in HVAC controller 34, along with other data used in the programted operation of HVAC controller 34. For example, while all of the various set-point temperatures are stored, a separate location is used to maintain the current mode set-point temperatures. Further, other various memory locations are used to store operational flags, manifesting, for example, the operational status of certain elements of the heating/cooling unit 38, or whether the condensate alarm is on. Other locations of the memory contain the progranmd instructions for causing various actions by the heating/cooling unit 38. For example, the heat may be turned on whenever the temperature measured by the temperature sensor in thermostat 42 indicates that the temperature in the facility is below the current mode heating set-point.

While the various modes, particularly HOME, AWAY and SLEEP, discussed above, may be entered by the user operating thermostat 42, they are normally entered under the control of microprocessor 58. Within RAM 60, a schedule table is maintained which indicates the normal schedule of the user. The schedule is based upon eight different day entries, Sunday through Saturday and a Holiday. In addition, a counter is maintained in RAM 60 which is constantly updated in response to interrupts from Clock Circuit 66 to maintain the current time. Generally, the schedule table is maintained by time of day for each of the eight possible day entries and at the appropriate time, it sends appropriate messages using the REC and XMIT lines from and to I/O ports 70 and 72. For example, at the user programmed time for a change from the AWAY mode to the HOME mode, microprocessor 58 provides a signal causing a change in the schedule flags address of the memory in HVAC controller 34. Upon accepting the signal from microprocessor 58, the HVAC controller 34 provides an acknowledgment (ACK) signal to microprocessor 58, or if appropriate, a not acknowledged (NAK) signal. In response to the mode change signal, the program in HVAC controller 34 changes the currently active set-point temperatures and the status flags.

The communications link between microprocessor 58 in scheduler/handler 30 and HVAC controller 34 uses a 1200 baud multi-drop serial asynchronous communication protocol. Each command begins with an address character, followed by a stated number of additional characters and ending with a checksum character. Each character in the communication contains eleven bits, the first of which is a start bit and the second is a "1" if the character is an address character and a "0" if the character is a non-address character. The next eight bits of a character contain binary data and the eleventh bit is a stop bit. All commands are initiated by microprocessor 58 in scheduler/controller 30 and HVAC controller 34 merely responds to the command it receives. Microprocessor 58 sends two basic types of commands, Read and Write. HVAC controller 34 responds to a Read command by providing a variable length Response including the requested data and responds to a Write command by providing either an ACK (acknowledgment) or a NAK (not acknowledged).

The Read command contains eight characters, beginning, as follows:

1. an Address character,

2. a Length character containing the binary number "1000001111", indicating six characters following the Address character,

3. a code character containing the binary code "10000100",

4. a character indicating the trunk to which HVAC controller 34 is connected, which is not used in the embodiment described herein and thus may contain any binary code,

5. a character indicating the address of HVAC controller 34, which is not used in the embodiment described herein and thus may contain any binary code,

6. a Start character, which may be a number between 0 and 255,

7. a character containing the number of bytes to be read, and

8. a Checksum character, which is the sum of all characters, except the address character, preceding the checksum character.

The HVAC controller 34 responds with a variable message containing the data requested, which takes the following form:

1. an Address character,

2. a Length character containing the binary number which indicates the number of characters following the Address character,

3. a code character containing the binary code "1100001011",

4. a character indicating the trunk to which HVAC controller 34 is connected, which is not used in the embodiment described herein and thus may contain any binary code,

5. a character indicating the address of HVAC controller 34, which is not used in the embodiment described herein and thus may contain any binary code,

6. a Start character, which is the same as the Start character in the Read command,

7. Data character 1

8. Data character N, and

9. a Checksum character, which is the sum of all characters, except the address, character, preceding the checksum character.

The Write command is of a variable length, and is organized as follows:

1. an Address character,

2. a Length character containing the binary number which indicates the number of characters following the Address character,

3. a code character containing the binary code "10000110",

4. a character indicating the trunk to which HVAC controller 34 is connected, which is not used in the embodiment described herein and thus may contain any binary code,

5. a character indicating the address of HVAC controller 34, which is not used in the embodiment described herein and thus may contain any binary code,

6. a Start character, which may be a number between 0 and 255,

7. a character containing the number of data bytes to be written,

8. Data character 1

9. Data character N, and

10. a Checksum character, which is the sum of all characters, except the address character, preceding the checksum character.

The ACK message is returned by HVAC controller 34 if it accepts the write command message, and takes the form:

1. an Address character,

2. a Length character containing the binary number "00000011", indicating three characters following the Address character,

3. a code character containing the binary code "00100000", and

4. a Checksum character, which is the sum of all characters, except the address character, preceding the checksum character.

The NAC message is returned by HVAC controller 34 if it has not accepted the write command message for some reason, usually because the checksum is not verified, and takes the form:

1. an Address character,

2. a Length character containing the binary number "0000001"L., indicating three characters following the Address character,

3. a code character containing the binary code "00100001", and

4. a Checksum character, which is the sum of all character, except the address character, preceding the checksum character.

Referring again to FIG. 3A, the communication between microprocessor 58 and transceiver 54 for controlling home automation is generally similar to that described above, except that the conventional and well known X-10 protocol is followed. However, it should be noted that other types of communication buses or links between the transceiver 54 and various devices 56 may be used in place of the X-10 bus, and in such case, the protocols of those other types of buses or links would be followed.

While the manner in which programmable thermostat 42 is used to control many of the HVAC controller 34 parameters has been described at length above, the primary manner of changing either the HVAC controller 34 parameters or the water heater and automation control unit 28 parameters, particularly after the initial installation, is done using any common telephone to cause the customer command center computer 22 to send a paging message.

An example of when such a change would be desired is when a person, who normally leaves work at 5:00 PM, desires to work late or go out for dinner. Since that person normally arrives home at, for example, 5:30 PM, the home is controlled to switch to the HOME mode for heating and air conditioning at 5:30 PM and no lights are automatically turned on by the home automation system. With a simple telephone call to the control center computer 22 (seen in FIG. 1), that person can cause the HVAC controller to remain in the AWAY mode, thereby saving energy, and can further cause the outside lights and one or more inside lights to automatically turn on to give the presence that the home is occupied.

The manner in which the control pursuant to the example of the preceding paragraph occurs is by customer command center computer 22 causing an appropriate message to be sent to the scheduler/controllers 30 and 44 in a designated facility. According to the preferred embodiment of this invention, these messages may be sent using conventional and available paging messages broadcast by, for example, the local telephone companies. With a twenty-three digit numeric paging message being used to transmit the message, nine,different types of messages may be transmitted and the microprocessors 58 in either scheduler/controller 30 or 44 are designed to accept these messages and respond, under program control, in an appropriate manner. Also, a tenth message type. is available for other message formats, such as the 80 character alpha-numeric type of paging messages. The ten types of message formats are set out below in Table II.

Referring now to FIG. 5, a diagram g enerally representing any of the various twenty-three character messages is shown. As seen from FIG. 5, the message consists of twenty-three characters, each being one of the digits "0" through "19". The first character of the message is an identification (I/D) digit maniifesting the type of the message, based upon the listing in Table II above. Thus, if the message sent is a Weather message, the first character contains the character information manifesting the digit "13". The next 21 characters contain the information of the message, as described in detail below, and the final character contains a parity, or checksum digit, which may based upon the sum of the digits of the first twenty-two characters.

Whenever a message is transmitted, it is received by every control unit 26 and 28 within every facility 12 responding to the particular phone number of the paging message. When the twenty-three character paging message is used, up to 1000 different control units 26 and 28 may share the same phone number and each is given an address code of "000" through "999". Some paging messages are to be acted upon by all control units 26 and 28, while others are addressed only to a specific control unit 26 or 28, and only that addressed control unit 26 or 28 responds. Further, the type of control unit 26 or 28 receiving the message will determine, in part, the information content of the message. For example, a type "0" Schedule Information message addressed to a HVAC control unit 26 will manifest different information than a type "0" message sent to a water heater and automation control unit 28.

Referring now to FIG. 6, three diagrams, labeled A, B and C, useful in understanding the Schedule Information messages are shown. As noted from Table II, there are two different Schedule Information messages and these are distinguished by the first character being either "0" or "1". The difference is that a Schedule Information message beginning with "0" is for controlling the schedule of devices "0" through "9" being controlled by water heater and automation control unit 28, whereas a Schedule Information message beginning with "1" is for devices "10" through "16" being controlled by water heater and automation control unit 28. For an HVAC control unit 26, either type message may be used.

Diagram A of FIG. 6 illustrates the format of the twentythree characters of a Schedule Information message. As seen, the first character is either a "0" or a "1" and manifests that, if the message is addressed to a water heater and automation control unit 28, it contains schedule information for either devices "0" through "9" if the first character is a "0" or devices "10" through "16" if the first character is a "1". It should be noted that the water heater 52 is always device "0" and the various devices 56 attached to transceiver 54 are devices "1" through "16". Then particular designation of each device being controlled is set using the protocols of the X-10, or other communication link, system being utilized.

The second through fourth characters of the Schedule Information message is an address code for the controller to which the Schedule Information message is intended to be sent. This may be any number between "000" and "999". Each scheduler/controller 30 and 44 is assigned with a specific address of between "000" and "999", which address is unique to that scheduler/controller This address may be stored in the EPROM memory 62, or it may be hard-wired within the scheduler/controller. Generally, when a signal is received, the program controlling each scheduler/controller 30 or 44 looks at the signal to see if it should react. For global signals, such as time and date information, a reaction is programmed to always occurs. For other signals, the program must examine the address code to see if the signal is intended for that scheduler/controller 30 or 44.

The fifth and sixth characters represent the device number being addressed, (fifth character) and the event information (sixth character). The fifth character will be any number between "0" and "9" and represents devices "0" to "9" if the first character is a "0" and devices "10" to "16" if the first character is a "1". The sixth character may be any number between "0" and "7", which can be converted to a three bit binary code by microprocessor 58. After such conversion, the two low order bits represent how many event commands follow and the high order bit is set if the message is the second of a two part event message. A schedule for any device can consist of up to eight different events, such as turn on a device at a particular time or turn off a device at a particular time. However, each of the Schedule Information signals only contains sufficient room for four event commands, and thus, where more than four are needed, a second Schedule Information signal is needed and this is indicated by the sixth character being one of the numbers four through seven.

Following the sixth characters are four event commands of four character each. The first event command is contained in characters seven through ten, the second event command in characters eleven through fourteen, the third event command in characters fifteen through eighteen and the fourth event command in characters nineteen through twenty-two. Diagram B of FIG. 6 illustrates any of the four character event commands, where the four characters of each event command are labeled only as first, second, third and fourth. For the first two characters of an event command, only the digits zero through seven may be used, and these digits are then converted into a three bit binary code by microprocessor 58. Hence, the first and second characters are shown as containing a "Not Used" most significant bit.

The high order bits of the three bits used in the first and second characters of each of the four event commands are dedicated to defining a day designation; hence they are referred to as the day flags. Since there are eight bits available for the day flag (two in each of the four event commands) each of the eight day designations, Sunday through Saturday and Holiday, may be specified by simply placing a "1" in the appropriate location of the appropriate command. It should be recalled at this point that each Schedule Information message is limited to one device for one day, with a maximum of eight different events for that device on that, day being controllable.

Generally, an event command for water heater and automation control unit 28 will be an "on" or "off" command, followed by a time to execute the command, although for some appliances, such as lights with dimmers, intermediate degrees of "on" are possible. An event signal for the HVAC control unit 26 is a mode change at a specified time. In any case, the time may be a specified time, or it may be an offset from either sunrise or sunset.

As seen in Diagram B of FIG. 6, the higher ordered bits are shown on the left and the lower ordered bits are shown on the right. The highest order bits of the first and second character are not used and the second highest order bits are dedicated to the day flag, as explained above. The two low order bits of the first event command character manifest the command itself. For a Schedule Information message being provided to water heater and automation control unit 28, the two bit command to the device designated in character five may be as follows:

The "High" and "Low" manifestations are intermediate settings of a dimmable light, for, example. For a Schedule Information message provided to the HVAC control unit 26, the two bit command is to enter the designated mode, at the time set out in the remainder of the event command. The designated modes are represented as follows:

The remainder of the Schedule Information message is dedicated to setting forth the time at which the command is to be executed. This time may be expressed either as an absolute time, or as an offset form either sunrise or sunset. If a sunrise or sunset offset time is being expressed, then the two low order bits of the second character will be binary "1-1", as seen in Diagram C of FIG. 6. Otherwise the two low order bits of the second character will manifest the tens digit of the absolute time, as seen in Diagram B of FIG. 6. As seen in Diagram B, for a nonsunrise/sunset time, the third character of the event command is the units digit of the hour and the fourth character represents the number of five minute increments past the hour designated by the second and third characters. With this arrangement, any time on a twenty-four hour basis in five minute increments, except times ending in XX:50 and XX:55 can be selected. While this is somewhat of a limitation, most events will be programmed on a quarter hour mbasis, and thus, the inability to program the occurrence of an event at fifty or fifty-five minutes past the hour is not significant.

Referring to Diagram C of FIG. 6, the organization of the information for a slunrise/sunset offset is shown. The first two characters and th e fourth character are as described with respect to Diagram B of FIG. 6. However the third character, for a sunrise/sunset offset time is limited to digits zero through seven, which converts to a three bit binary code. When the high order bit is a fill, it designates an offset from sunset and when it is a "0", it designates an offset from sunrise. If the middle bit of the three bits of the third character is a "1", the offset is to be subtracted from the designated sunrise or sunset. On the other hand, if the middle bit of the three bits of the third character is a "0", the offset is to be added to the designated sunrise or sunset. If the low order bit of the third character is "1", then sixty minutes is to be added to the zero to forty-five minutes value in the fourth character. If the low order bit of the third character is a "0", then the value in the fourth character is the offset.

Referring now to FIG. 7, two Diagrams A and B, are shown. Diagram A illustrates the composition of the Time, Date anld Daylight Message is shown and Diagram B illustrates the Holidaiy message. The Time, Date and Daylight message of Diagram A and the Holiday message shown in Diagram B are provided to all control units 26 and 28 which respond to the pager telephone number. The Time, Date and Daylight message of Diagram A is periodically provided such as every fifteen minutes, in order to maintain the correct time for all control units 26 and 28 and in order to provide certain sever cold weather information in a timely manner. In addition, the time of sunrise and sunset is adjusted every day. The Holiday message, seen in Diagram B of FIG. 7, on the other hand, is only provided twice a day on the day before the designated holiday.

Referring specifically to Diagram A of FIG. 7, the I/D in the first character is a "12", indicating either a Time, Date and Daylight message or a Holiday message. For a Time, Date and Daylight message, characters two through five indicate the time, with characters two and three manifesting the current hour on a twenty four hour basis, and characters four and five manifesting the minute. In character two is a "13", then the Holiday message, shown in Diagram B, is indicated, as no hour can begin with a tens digit of three. Character six is a code from zero to seven indicating the day of the week. Specifically, characters zero through six represent Sunday through Saturday respectively, and character seven represents a holiday.

The next six characters of the Time, Date and Daylight message represent the current date, with characters seven and eight representing the month, characters nine and ten representing the day of the month and characters eleven and twelve representing the last two digits of the year. Character thirteen is sever cold temperature flag, which is set whenever very cold weather is anticipated and used in disabling a heat pump and enabling heat strips. Finally, characters fourteen and fifteen are an offset value from 4:00 AM in five minute increments to sunrise and characters sixteen and seventeen are an offset value from 4:00 PM in five minute increments to sunset. Characters eighteen through twenty represent the Julian Day count, which is the cumulative day count in any year, beginning with January 1 as day one. Characters twenty-one and twenty-two are not used and normally are zero and character twenty-three is a checksum digit.

The Time, Date and Daylight message is also used by each of the control units 26 and 28 to reset the proper time after a power-outage. It should be noted that the power supply includes a large capacitor attached, to the power output supplying RAM 60. This capacitor maintains power for up to two weeks in the event of a power outage, so the data stored in RAM 60 is not lost. However, the clock circuit 66 and microprocessor 58 are not operated during power outages and thus the time and date needs to be updated. Thus, the Time, Date and Daylight message is provided frequently, such as every fifteen minutes, to update the time and date information.

Diagram B of FIG. 7 shows the composition of the Holiday message, which is indicated if character one is a "2" and character two is a "3". Character three is not used and the sixteen characters four through nineteen are each limited to digits "0" through "7". Thus, the sixteen digits in characters four through nineteen may be used to represent forty-eight different predesignated holidays by decoding these digits to a binary coded decimal format and ignoring the high order bit. As will be explained hereafter with respect to the initialization message in FIG. 9, each user of system 10 may designate only those of the pre-designated available holidays that are appropriate to the user's life style. In addition, users may designate their own holidays using the system parameter message shown in Diagram F of FIG. 13B. Finally, characters twenty through twenty-two of the Holiday message of Diagram B of FIG. 7 represent the Julian day and character twenty-three is a checksum, digit.

Referring now to FIG. 8, a diagram illustrating the Weather Infiormation message is shown. The Weather Information message begins with an I/D code of "3" and is broadcast to all control units 26 and 28, either when the we ather changes, or alternately, one or more of these messages may follow the broadcast of the Tiume, Date and Daylight message. The second character is a number between zero and nine manifesting a type of weather indicator. For example, rainy, cloudy, humid, hot, sunny, and so forth may be represented by different numbers in character two. The next twenty characters manifest a two digit value for the identified weather information in each of ten different weather zones. A "00" in a zone portion of the weather message indicates that no change from the last weather message has occurred and any other number iiay indicate the degree of the type of weather indicated by the digit in character two. Each control unit 26 and 28 is programmed to know into which zone it falls, and thus,, there the weather information is more localized than the area served by the paging transmitter. The final digit of the weather message is the checksum digit.

Referring now to FIG. 91 a diagram illustrating the Initialization message is shown and begins with an lID code of "14". The Initialization message is generally provided in response to a telephone call to the customer command center computer 22, normally by an installer, at the time the customer premise equipment is installed. The Initialization message may be used to set the various parameters to the predefined default values, or it may be issued merely to see if the pager receiver 32 or 46 is set in the facility at a location to receive pager signals. The second through fourth characters manifest the address of the particular control units 26 and 28 requesting the initialization. The fifth character may be "0", "1", "3", "5" or "6" to indicate the type of information being transmitted in the following characters. Finally, the twenty-third, or last digit, is a checksum digit. Specifically, if character five is a "0", then no data follows and if character five is a "1", then the data in the locations sjLx through twenty-two is the default settings for various seventeen devices being controlled by facility automation control unit 28. These characters may each contain a value between zero and three. Similarly, if character five is a "3", then the data in characters six through twenty-two is the default settings for various HVAC parameters used in HVAC control unit 26. If character five is "5", then the data contained in characters six through twenty-one manifests the user's selection of the appropriate pre-designated holidays. The encoding for characters six through twenty-one is the same as described above with respect to characters four to nineteen in Diagram B of FIG. 7. Finally, if character five contains the value "6", then characters six and seven contain a two digit house code and characters seven and eight contain a two digit weather region. This information is used to designate the weather zone for the user in order to respond to the weather message shown in FIG. 8.

Referring now to FIGS. 10 and 11, two messages initiated by a electric power utility company may also be sent to individual ones of the control units 26 and 28. These messages are used by the utility company to assist it in more equitably reducing power consumption under circumstances when the potential demand for power exceeds the ability of the utility company to generate power. In the past, the utility company has turned off the power completely for selected user groups or load groups when load reduction was required. In the past, there has been no ability for the utility company merely reduce the energy usage of selective devices, as opposed to completely disabling the devices for predetermined periods of time.

Alternate methods of reducing power loads are preferable to completely eliminating the power from an entire neighborhood. For example, a reduction in power consumption can occur by raising the temperature which all air conditioners begin cooling and this reduction in power consumption over a slightly wider area may be as great as the consumption reduction from turning off all power to a given neighborhood. Alternatively, a reduction in power may be achieved by merely permitting an air conditioner or water heater to run for only a certain time, or to run only after a certain time has elapsed since the last operation. In the latter cases, the convenience for the consumer is much better since all power is not reduced and some air conditioning or hot water generation is still available. The two utility company messages shown in FIGS. 10 and 11, operating in conjunction with the other equipment described above, permits an improved manner of permitting a utility company to reduce consumption.

The Utility Setup Message, seen in FIG. 10, begins with an I/D character of "5" and is sent to a specific control unit 26 or 28 addressed by characters two through four. Following the control unit address, an eight digit Individual Recognition Code contained in characters five through twelve is sent and stored in the RAM memory 60 associated with microprocessor 58. The particular eight digit Individual Recognition code is developed by the utility company in order to permit equitable power reduction among its customers and may be unique for each control unit 26 or 28, or unique for every control unit 26 or 28 in a selected area. It should be noted that the Utility Company Setup message is only sent to those customers of the utility company agreeing to participate in the power reduction program, for which the utility company must give some concessions, such as a lower rate to encourage participation.

In the recognition code, only the digits zero through eight are used, so that when the code is later addressed by the Utility Company Activation message, the character nine can be used as a wildcard, or a digit not requiring a match to be recognized. An example of a recognition code may use the first digit to designate the particular utility company, the next two digits to designate a utility company division, the next three digits to designate a region within a division, and the final three digits to identify a sector within a region. It is necessary to use at least one character to designate the particular utility company because the area served by a paging system may cover areas covered by more than one utility company.

Once each participating facility has been setup with a recognition code, the utility company can selectively address those control units 26 and 28 for which it desires to reduce consumption. This is accomplished by transmitting the Utility Company Activation message, seen in FIG. 11. The Utility Company Activation message is broadcast to all control units 26 and 28 and begins with the I/D character "6". Next the message has an eight digit Shedding Recognition Code, which is generated by the utility company to access those control units 26 and 28 which are to be controlled to use less power. Because of the ability to use the wildcard digit "9" in the recognition code, a large number of control units 26 and 28 may be reached using a single message, or alternatively, only those control units 26 and 28 in a specific territory requiring load reduction may be selected. For example, a recognition code of 19999008 may address every control unit 26 or 28 served by utility company "1" within sector 008 of all regions and divisions. After the Shedding Recognition Code, the remainder of the Utilily Company Activation message contains various instructions and parameters dictating the manner in which the loads are to be reduced.

It should be understood that each of the HVAC control units 26 only control heating and air conditioning units, so the program therein responds to the Utility Company Activation message in a manner consistent with reducing the power consumption of a heating or cooling unit. On the other hand, the water heater and automation control unit 28 controls both a water heater, which consumes a substantial amount of energy and up to sixteen additional devices, such as lights, pumps, appliances and the like, which typically do not consume as much power. Thus, the water heater and automation control unit 28 may be programmed to only respond to power curtailment for the water heater, but not for the remaining items, such as lights and small appliances, being controlled. This is easily done, since the water heater is always device zero, whereas the remaining devices being controlled may be assigned any device number from one to sixteen.

The remaining data in the Utility Company Activation message permits various load reduction strategies to be adopted. For example, characters ten and eleven contain a two digit number manifesting, in minutes, a time to delay activating the load reduction operation. Character twelve, if set, indicates that the delay is to begin and end in a randomized manner over the set delay time, so that all units do not turn on at the same time after the reduction period. This technique permits total deactivation of the energy consuming device in a randomized order if desired.

The next six characters of the Utility Company Activation Message permits the energy usage of the heating/cooling units 38 or water heater 52 to be reduced, but not totally taken out of service. Specifically, characters thirteen and fourteen contain a two digit entry representing a time, in minutes, of a curtailment cycle, characters fifteen and sixteen contain a two digit numbier representing the percent of the cycle during which the loald reduction is to occur and characters seventeen and eighteen contain a two digit character representing the number of times to repeat the cycle. With this data, the control units 26 and 28 respond by disabling the heating/cooling units 38 or water heater 52 for a certain percentage of each defined cycle time. For example, a cycle may be defined as thirty minutes and the percent of the cycle to reduce the load may be fifty percent; thus, during the first fifteen minutes of each half hour, the water heater 52 or heating/cooling unit 38 is disabled. Further, this cycle may be repeated as many times as directed.

The next four characters of the Utility Company Activation message is used only with respect to HVAC control units 26. Characters nineteen and twenty contain a two digit heating setpoint temperature and characters twenty-one and twenty-two contain a cooling set-point temperature. By sending a Utility Company Activation message with these set-point temperatures, the utility company can merely affect at what temperatures the heating or cooling occurs. For example, in hot weather, the utility company can limit air condition to a certain temperature, such as for example, 840.degree. F. and in cold weather, the utility company can limit the temperature at which heating occurs, such as for example 65.degree. F. In the past, it has never been possible to adopt a mandatory power load reduction strategy by merely adjusting the interior temperatures at which heating or cooling occurs. However, power companies have historically requested voluntary compliance with this type of strategy without the ability to enforce adherence.

Referring now to FIG. 12, a diagram illustrating the User Override message is shown. As previously noted, the user can manually override certain modes in the HVAC control unit 16 using the ON key 84 of thermostat 42. Generally, an override means to return the unit being controlled to the normal setting when the facility is occupied. In the case of HVAC control unit 26, this means returning the mode to the HOME mode of operation where the temperature heating set-points are at the highest value and the cooling set-points are at the lowest value. With respect to the water heater and automation control unit 28, the water heater, for example, will be permitted to heat the water, whereas the normal schedule for the water heater is to be disabled during periods of time no one occupies the facility.

In certain instances, a user of system 10 may desire to return home prior to a normal return time, and in such instance, would want the home at the proper HOME mode temperature and the water heater ready to provide sufficient hot water for a shower. This can be done by simply calling the customer command center computer 22 and directing that the control units be overridden for certain energy consuming devices. The manner in which the user communicates with the customer command center computer 22 will be described hereafter. After a proper order has been received by the customer command center computer 22, the User Override message is transmitted over the paging network.

As seen in FIG. 12, the first digit of the User Override message is a "7", and is followed by the three digit address code for the control unit 26 or 28 being overridden. Next, characters five and six contain a two digit code manifesting the device number of the device to be overridden. Thus, normally, characters five and six will contain a value between zero and seventeen. If the value in characters five and six is eighteen, then all devices being controlled are designated to be overridden to the default value. Finally, if the value in character 5 is a two, then, the override is designated to a specific set of states for the devices being controlled. This is referred to herein as a mood string and may be any combination of devices operating previously designated by the user. Next, character seven contains a single digit manifesting the desired state of the device after the override. This digit may be between zero and three and may be similar to the Command code in an Event command of the Schedule Information message, as described above with respect to diagram B of FIG. 6. Next, the User Override message contains, in characters eight through eleven, four digits representing the hours and minutes of the desired override.

In some instances, the user does not desire to have the override occur until some point of time in the future, as opposed to immediately. In order to permit this future scheduling of override messages, characters twelve through twenty-one permit a date and time for the override to occur. Specifically, characters twelve and thirteen contain a two digit code representing the month in which the override is to occur, characters fourteen and fifteen contain a two digit code representing the day of the month in which the override is to occur, characters sixteen and seventeen contain a two digit code representing the year in which the override is to occur, characters eighteen and nineteen contain a two digit code representing the hour at which the override is to occur and characters twenty and twenty-one contain a two digit code representing the minute at which the override is to occur. In this scheme, character twenty-two is not used and as usual, character twenty-three is a checksum digit.

Referring now to FIGS. 13A and 13B, the System Parameter message is illustrated using diagrams A through F. The System Parameter message is used to permanently program the control units 26 and 28 and is used initially by the installers at initial installation and thereafter by the user any time a permanent schedule parameter change is desired to be implemented. This message should be contrasted with the Schedule Information message, which is used to send the time of various schedules, whereas the System Parameter message is used to set the parameters to be used at the time a particular scheduled event is to occur. For example, the Schedule Information message programs the scheduled time for HVAC control unit 26 causes the interior temperature to change as a result of a change from the AWAY mode to the HOME mode. On the other hand, the System Parameter message programs the various setpoint temperatures during the HOME an AWAY modes.

The basic System Parameter message is shown in diagram A of FIG. 13A, and begins with the I/D character "8" as the first character, followed by the three digit address of a control unit 26 or 28 as characters two through four. Next, character 5 contains a Type code, which may be the digits one through six, respectively manifesting:

Type 1--Device low level values Type 2--Device high level values Type 3--HVAC temperature set-points Type 4--Mood Strings Type 5--First Five User Selected Holidays Type 6--Second Five User Selected Holidays After the type character, the next seventeen characters, six through twenty-two, contain the message portion of the System Parameter message. The message portion of the various types of System Parameter message are shown in Diagrams B and C of FIG. 13A and Diagrams D, E and F of FIG. 13B.

Diagram B of FIG. 13A shows the format of the type 1 and type 2 message portions of the System Parameter message. The type 1 message specifies the low dimming level for up to seventeen devices (designated as devices 0 through 17) under control of control unit 20, whereas the type 2 message controls the high dimming level for those seventeen devices. As seen in diagram B, the format of the message portion of the type 1 or type 2 System Parameter message is a single digit having a value of between zero and nine in each of character positions six through twenty- two, each representing devices zero through sixteen respectively.

Diagram C of FIG. 13A shows the format of the type 3 message portion of the System Parameter message, which is used to set the various temperature set-points in an HVAC control unit 28. The format is a series of two digit value in character positions six through twenty-one, representing the following set-point values:

Character 22 is not used in the type three System Parameter message.

Referring now to FIG. 13B, Diagrams D and E represents the Type 4 Mood String message, which occurs when character five of the System Parameter Message is a "4". Up to ten different mood strings can be designated by the user and these are identified by the value ("0" through "9") in character six. As noted above, a mood string is activated by the override message discussed above with respect to FIG. 12. Each mood string may include up to seven different events, and each event is respectively specified in the next seven character pairs eight-nine, ten-eleven, twelve-thirteen, fourteen-fifteen, sixteen-seventeen, eighteen-nineteen and twenty-twenty-one. Character twenty-two is not used and character twenty-three contains the checksum digit.

Each of the two character events of the mood string message are shown in diagram E of FIG. 13B. The highest order bit of the binary decoded version of the first event character is not used. Thus, the first event character of a mood string message may only contain values of "0" through "7". The next highest order bit of the first event character represents the tens digit of the device number and the two low order characters of the first event character are the status of the designated device to be controlled, represented as follows:

Finally, the second character of the event represents the units digit of the device number.

Referring now to FIG. 14, the final type of message is seen which can be sent from transmitter 20 to the various control units 26 and 28 is the Expanded message. The Expanded message format may be defined to use the eighty character alpha-numeric paging signal. Thus, each of the eighty characters of the expanded message may contain any value between zero and "255". However, to prevent this signal from interfering with the equipment described herein, the first character cannot begin with values between zero and eight.

With the exception of the Time, Date and-Daylight message and Holiday message shown in FIG. 7 and the Weather Information message shown in FIG. 8, which are automatically sent out at a periodic interval, the remaining messages require some direction to the customer command center computer 22 in order to cause a transmission. Except for the Utility Company Setup and Utility company Activation messages, shown in FIGS. 10 and 11, this communication is normally from the homeowner or installer and normally occurs via telephone. Within the customer command center computer 22, an automatic telephone communication system is used, in conjunction with a digitized voice platform, to request actions desired by the caller be designated by pressing various buttons on a telephone. In order to initiate a message, the caller must first enter his or her own telephone number, followed by a personal identification number (PID). Based upon that information, the customer command center computer 22 can determine the identity of the user, the type of controllers 26 or 28 installed and the type of equipment being controlled by each control unit 26 or 28. Wilth this information, the customer command center computer 22, through pre-programmed voice messages accessing the digitized voice platform, then asks various questions which can be answered by pressing the keys on a DTMF tone telephone.

Generally, a customer can select one of the many predefined schedules which are published to the user and assigned a number. For example, a published heating/air conditioning schedule, which includes heating or cooling sleeping areas, may be as see FIG. 15. If the homeowner has a second heating/cooling unit which is only used to heat or cool common- areas where no person sleeps, a similar schedule to that shown above is used, but all codes are increased by one. The principal difference is that if the second mentioned schedule is used, the AWAY mode set- points are used in place of the SLEEP mode set-points. In using the published schedule, a person's home occupancy and sleeping habits may be conveniently entered by merely entering a three digit number for each day. However, if a person's occupancy and sleeping habits are not included in the published schedules, a custom schedule may be entered, although it may a longer time to enter the data. Alternatively, the provider of the service may enter the customized schedule for its customers based upon information provided by the customer.

Similar schedules are published for times hot water is needed, lights are to be automatically turned on or off, pool pump or sprinkler motors are to be turned on, and the like. With respect to the lights, the schedules may be based on turning lights on at or a fixed time from sunset and turning them off at or a fixed time from sunrise.

In addition to the published schedules, the customer command center computer 22 permits the user to identify appliances placed on the X-10 bus by their common name or in the case of lights, by a room identification. For example, device number one may be the coffee maker, and device number two may be the lights in "Boy's Room", or "Third Bedroom".

A typical conversation between a user and the customer command center computer 22, where the user wishes to turn the water heater on for the next two and a half hours.about., may be as follows:

Computer: Hello, this is the Command Center. Please enter your

home area code and telephone number.

Customer: enters ten digit number.

Computer: Thank you. Please enter your personal identification number.

Customer: enters four digit PIN code.

Computer: Thank you. You are now at the Main Menu. Please choose a category. For Heating and Air Conditioning, press 1; for water heating, press 2; for lights that your only turn on or off, press 3; for lights that you dim, press 4; for appliances, press 5.

Customer: presses 2.

Computer: Water Heater, Actions choices follow: To override ON, press 1; to override off, press 2; to return to your normal schedule, press 3; to assign an energy guide schedule, press 4; to return to the main menu, press *.

Customer: presses 1.

Computer: Please enter the override duration in hours and minuters. First enter the number of hours.

Customer: enters 2.

Computer: Now enter the number of minutes.

Customer: enters 30.

Computer: To put your water heater on for two hours and thirty minutes, press 1. To choose a different action for this device, press 2. To return to the main menu, press *.

Customer: presses 1.

Computer: Your water heater will be overridden on for two hours and thirty minutes. Thank you for calling the Command Center. Good-bye.

Attached hereto as Appendix I is a listing of the various words and phrases which can be generated by the digitized voicie platform of customer command center computer 22.

Within customer command center computer 22, a database ins maintained containing information regarding each user. Such information includes the types and names of the various equipment of each user, the modes of operation and schedules as programmed byd the user, the various set-point temperatures and other parameters as set by the user, and so forth. When the user calls the customer command center computer 22, the program therein uses the data base and the prior responses of the customer to generate the next appropriate series of choices for the user. The query generated by customer command center computer 22 that is common for each customer is the request to enter the telephone number and personal identification code. Even the main menu is uniquely generated for the customer, because some customers will not control items other than HVAC units, whereas others will control many different energy consuming devices. Thus, unlike other systems, there is no set series of programmed queries, but rather, each user has a unique sequence of queries, built from the data stored in the database record for that user and in response to prior queries.

With respect to the Utility Company messages, seen in FIGS. 10 and 11, they may generated by the utility company and provided directly to transmitter 20, or through customer command center computer 22 for transmission to the various control units 26 and 28. Referring now to FIG. 16, a broad view flow diagram of the program controlling microprocessors 58 in FIGS. 3A and 3B is shown. A copy of the object code of the entire program is attached hereto as Appendix II. By constructing the apparatus described herein in FIGS. 3A or 3B and placing the program set out ire Appendix II, the operations described herein are obtained. The set of instructions constituting the program for microprocessors 58 is contained in EPROM 62 and the general operation of microprocessor 58, RAM memory 60, EPROM memory 62 in operating microprocessor is well known. Generally, the program merely proceeds through a loop checking if various activities are required to be performed. In addition, two interrupt signals can occur, which cause a deviation from the main program to service the interrupt. The highest priority interrupt is the TIMER signal, which occurs every 8.33 milliseconds, and is provided to the non-maskable interrupt (NMI) input of microprocessor 58. Whenever a TIMER signal occurs, the time of day-counter is updated, whereby, the correct time is always maintained.

The other interrupt signal occurs whenever the pager receiver 32 or 46 has received a message. As this signal is received by the pager receiver 32 or 46, it is decoded and saved in a seven segment format. After the pager message is received and decoded, it is provided as the PDATA serial signal to the display output lines of the pager receiver 32 or 46, one bit at a time, in synchronism with the CLOCK signal. As previously noted, the first CLOCK signal of a new message also interrupts microprocessor 58, which disables the INT input for a time sufficient to permit the entire PDATA message to be transmitted to shift register 82. The first panel of eleven or twelve seven segment signals are then stored in shift register 82 while the INT interrupt is disabled. After the interrupt disable time expires the data stored in shift register 82 is read by microprocessor and each bit is stored in an appropriate memory location relating to which character and. segment it represents. After all ninety two bits are transferred and the eighty-four segment bits are appropriately sorted and stored, the program of microprocessor 58 causes a seven segment to BCD (binary coded decimal) decoding for each sorted character to occur using conventional table look-up techniques. Thus, if a seven segment sorted group of signals represents a "9", the decoding results in a "1-0-0-1" being stored as the particular character.

After the first panel of the message is transferred to microcomputer 58, the READ signal is caused to issue and the above procedure is repeated for the second panel of the twenty-three character message. At this time, the entire pager message is stored in RAM 60 in a manner which can be acted upon by the remainder of the program of microprocessor 58. This may be indicated by setting a pager message flag.

The Main loop of the program controlling microprocessor 58 begins at block 100 by determining if the telephone interface 36 or 48 requires servicing. If telephone interface service is required, then according to block 102, the information sent to the telephone interface 36 or 48 is processed. Typically, such information will only occur during installation and will consist of the Initialization messages, seen in FIG. 9, or the initial Schedule Information messages seen in FIG. 6. The processing consists of storing the information received in the appropriate portions of RAM 60. Any other two way communication over telephone lines between system 10 and other points is also handled at block 102. For example, if system 10 or the telephone interfaces 36 or 48 are extended to include an auto-dialer and one or more of the X-10 devices 56 serves as a meter reading device, then the results of the meter reading would be sent to the utility company at this point using the telephone interface module. Alternatively, a utility company could pole the data saved by HVAC controller 34 to determine if energy were being efficiently used.

If the telephone interface does not require servicing, or if the servicing is completed, then the next event, as indicated by block 104, is to determine if a paging signal has caused information to be stored in shift register 82. This may be determined by determining if a pager interrupt has occurred and expired, thereby indicating that the pager data is stored in shift register 82. If so, then, according to block 106, the pager data is transferred to microprocessor 58, sorted and stored in RAM 60.

Then, according to block 108, a determination is made whether all of the data from shift register 82 has been stored in RAM 60 and is ready for decoding. If so, block 110 caused the stored seven segment data to be checked and, if proper, decoded. After decoding, the data is stored in the appropriate portions of RAM 60, as appropriate, or other actions dictated are performed in response to the message. For example, if the message provides a new HOME mode heating set-point temperature, the value of that new parameter is stored in RAM 60 and a flag is set indicating the new value Ls to be provided to the HVAC controller 34.

Next, various tasks are performed, as necessary, and thereafter, the entire Main loop is repeated. The various tasks performed in each loop are the Scheduler task, as indicated by block 112, the HVAC task, as indicated by block 114, the Countdown Time task, as indicated by block 116 and the Utilities task, as indicated by block 118. The Scheduler Task module 112 generally determines if it is time to turn on or turn off some appliance being controlled by water heater and automation controller 28 and then provides the appropriate signal to accomplish that task. It also keeps track of the current state of all devices being controlled. In calculating the next event to be performed, the Scheduler considers,the program schedule, the unprocessed customer override messages and any current utility override messages.

The scheduler module also considers an advanced start time (explained hereafter with respect to block 114), which is a time to reach the proper set-point temperatures when changing to a more demanding mode. This advance start time permits the temperature of the facility to be correct when the change of modes occurs. When conflicts in the schedule of events to occur results, the priority is first, the utility override, second, the user override, third, the advance start time and finally, the schedule itself. The scheduler also determines whether a device is already in the scheduled state at the time it finds an event is to occur, in which case, the event is ignored. For example, a light may be scheduled to be turned on at a certain time, but previously had been turned on by a user override message. In such case, no signal is sert again turning that light an.

The HVAC Task module 114 determines three variables which are used by the scheduler module 112 in providing proper data and control information to the HVAC controller 34. The three variables determined by the HVAC task module 114 are calculating the advance start time, monitoring the heating or cooling demand and monitoring whether heat strips are required in the event a reverse cycle heat pump is used as the heating/cooling unit 38. The manner in which the HVAC task module 114 performs these functions will be described hereafter.

The key to the operation of the Scheduler Task module 112 and HVAC Task module 114 is knowing the time an action is to occur. This time is determined by the Countdown Timer Task module 116 .intg.. determine the time an action is to occur, a schedule is maintained for all devices being controlled for the entire week. Then, the next event is determined from the schedule and a timer is set to indicate when that next event is to occur. The basic schedule is primarily a day scheduler, which contains up to one hundred entries, each containing up to eight events and the time of each events for a single device. For some events, it is necessary to calculate the time for each event based upon information provided to microprocessor. For example, the lighting commands based upon sunset and sunrise times must be calculated based upon the sunrise and sunset times provided to controller units 26 and 28 by the Time, Date and Daylight message, shown in FIG. 7.

After the various time tasks are completed, the Utilities Tasks module 118 is executed if any Utility messages have been provided. As previously described, these messages would either be a Utility Initialization message, or a Utility Activation message. If a Utility Activation message is received, the information is transferred to the schedule so that the next time the scheduler task module 112 is executed, the utility order is followed.

As noted above, an advance start time must be calculated. This is the time necessary to raise or lower the temperature to the next mode set-point by the time the next mode commences. For example, where the AWAY mode is to end and the HOME mode is to begin at 5:00 PM, that is, the user returns home from work at 5:00 PM, the user expects the home to be at the HOME mode temperature when he or she enters the facility. Thus, the heating or cooling must begin at some time, referred to herein as the advance start time, prior to the time the person returns. An advance start time is calculated whenever the mode (HOME, AWAY or SLEEP) changes to a more energy demanding mode.

In calculating,the advanced start time for any facility, many factors must be considered, such as, the temperature difference to make up, the outside temperature and other weather conditions, the insulation of the facility and the capacity of the heating/cooling unit 38 being used. In the past, the advance start times have been specified to each energy management systems based only upon the weather factors alone. However, this strategy is wasteful of energy for thermally efficient facilities and generally was too short a time for thermally inefficient facilities, or facilities with under capacity heating/cooling units. The program controlling microprocessor 58 adopts a different approach to determining the advance start and advance stop times. It calculates them based upon historical data for the particular facility and thus obtains a much more accurate advance start or advance stop time.

To calculate the advance start or advance stop times, the program makes use of the data generated by and stored in the HVAIC controller 34. Specifically, program uses a learning algorithm which will adapt over time to changing conditions. Briefly, current demand is monitored and a prediction is made of how much time will be required to attain the temperature goal. Then, the mode change is set to change at this advanced time.

The algorithm uses a weighted average value based upon the most recent heating/cooling history. For example, the most recent current demand values are multiplied by three and added to the next most recent demand value, multiplied by two, and this sum is added to the preceding four next most recent demand values. This sum is then divided by nine to arrive at an average demand value. This history may be limited to only heating or cooling calls during a recent period, such as two hours, and if six events do not occur, only those which do occur are used and then the divisor is adjusted appropriately. The current demand value is the heating or cooling ramp as percent signals and thus will be between zero and one hundred.

With this average demand signal, the following calculation is made by microprocessor to obtain the advance start time:

Advanced Start Time={(Avg. Demand) (K.sub.1)+(K.sub.2)}(.delta.T)+K.sub.3 (.delta.T-4)

where K.sub.1 is a heating or cooling multiplier between zero and sixty (initial setting of twenty) that is constantly modified, as needed, after the fact to have provided the correct value, K.sub.2 is a constant equal to a minimum minutes per degree time, which generally is set to a value of one, .delta.T is the required temperature change as a result of the new mode, and K.sub.3 is a constant used only when .delta.T is more than four degrees and is initially set equal to five, although it may be changed by an appropriate message signal. After each advance time calculation, the value of K.sub.1 may be adjusted. If after several days, the value of K.sub.1 is not relatively constant, than the values of K.sub.2 and K.sub.3 may also be adjusted by appropriate measures.

In some instances, there may not be any recent heating or cooling demand information and it would not be possible to calculate an advance start time. For example, where the temperature outside is approximately the same as the AWAY set-point, it is not likely that the heating/cooling unit 38 will be turned on. In this situation, the heating/cooling unit 38 is forced on for a defined time and the temperature change is measured. From this information, an approximation of the Average Demand value can be approximated.

When the user's heating/cooling unit 38 is a reverse cycle heat pump, having one or two states of auxiliary electric heat strips, special energy savings strategies are employed. This strategy is based on the fact that the most efficient heating occurs by the heat pump alone, without need for the heat strips. First, the heat strips are disabled in all modes except the most energy demanding mode. Then, the need for the heat strips is monitored and they are only engaged if actually needed. This may be done by monitoring the heat call variable from HVAC controller 34 and if it is at 99, (indicating that the temperature is dropping even though the heating unit is continuously enabled for the entire ramp time), the first heat strip is enabled. If the heat call variable remains at 99 twenty minutes later, then the second heat strip is enabled.

In performing the advance start heating task, it is most desirable to raise the temperature, if possible, using only the heat pump. Thus, after the advance start time is calculated, as explained above, and the heat pump heating/cooling unit 38 is rendered operational, the heat strips are initially maintained off. During the advance start heat recovery period, the rate of recovery is monitored and a determination is made whether the heat pump alone will permit the set-point temperature to be reached by the end of the advanced start period. If not, then one stage of heat strips is enabled and again, the recovery is continually monitored. If it still appears that the set-point temperature will not be reached by the end of the period, the second stage of heat strips are enabled.

There are two situations where the heat strips are permitted to operate in the lower energy consuming modes and in the recovery period. First, if the system is overridden to a higher energy consuming mode by either a manual actuation of the ON key 84 on thermostat 42 or by an override message indicating a change to a higher energy consuming mode, the heat strips are permitted to operate normally. Second, if the severe weather flag is set in the Time, Date and Daylight message, seen in FIG. 7, then the heat strips are permitted to operate and the heat pump is disabled because in cold weather, the heat pump is very inefficient. Once the severe weather flag ceases being set, the heat pump is engaged and the heat strips are disabled.

While the energy management and home automation system of this invention has been described in great detail herein and with many examples, it should be appreciated that many variations and additions are possible, particularly in using the various message structures to command additional functions. Further, other communication links between the command centers 22 and 24 and the controllers 14 and between the controllers 14 and the various devices 18 being controlled are possible. It is also possible to include intelligent devices, such as personal computers, as devices attached to controllers 14 and then to permit various other devices to be attached to the intelligent device. ##SPC1##