Energy management system

• US 5,682,949 A
• Filed: 05/18/1993
• Issued: 11/04/1997
• Est. Priority Date: 05/22/1992
• Status: Expired due to Fees

• Current Assignee: Globalmic, Inc.
• Original Assignee: Globalmic, Inc.
• Inventors: Ratcliffe, Edward L., Page, Iain, Chami, Anwar
• Primary Examiner(s): Ford, John K.
• Application Number:
  US08/063,465
• Time in Patent Office: 1,631 Days
• Field of Search: 165/12, 165/22, 236/49.3, 236/51, 236/1 B, 236/1 C, 340/825.06, 364/505
• US Class Current: 165/209
• CPC Class Codes: F24F 11/54 using one central controller connected to several sub-controllers
• CPC Class Codes: G05D 23/1905 associated with tele control

Abstract

This document describes an energy management system in which microprocessor based thermostats are used to control individual room temperatures in a multiple room building in accordance with the known occupancy status of the room. The occupancy status information, as well as other control parameters, are transmitted to the thermostats from a central computer program. The control of a heating and cooling appliances is performed by an algorithm running on the electronic thermostat, which performs this function in accordance with these downloaded parameters. The system, allows room occupants to control the temperature of an occupied room within preset limits, automatically limits energy usage in unoccupied rooms, and provides additional facilities for energy management and general building management.

Claims

1. An energy management system for use in a multi-room building, comprising:

a plurality of electronic thermostats, each said thermostat being adapted to be located in one of said rooms for controlling the ambient temperature in said room, each said thermostat having;

temperature sensor means for producing an electrical signal representative of the ambient temperature in said room;

memory means having a thermostat configuration table for storing user specified parameters and status conditions respecting said room and for storing an algorithm for controlling said ambient temperature, said parameters and status conditions including the value of the maximum and the minimum ambient temperatures for said room, the occupancy status of said room, a bias temperature value for said room, a cooling unit status condition, a heating unit status condition, a default set temperature value, a peak load value, a maximum room temperature value, a minimum room temperature value, a pay television status condition, a theft protection status condition and a hysteresis value, said memory means further including a "maid in room" register, a "maid left room" register, a "room inspected" register, and a "theft flag" register;

occupant input means including first input means for enabling a room occupant to input a temperature increase or decrease signal, second input means for enabling a room occupant to input a "maid in room" condition, third input means for enabling a room occupant to input a "maid left room" condition, and fourth input means for enabling a room occupant to input a "room inspected" condition;

an output terminal bank for connecting said thermostat to a heating unit, a cooling unit, at least one circuit to be monitored for theft or electrical components connected thereto, and a circuit for energizing and de-energizing a pay television circuit;

a serial port for receiving and transmitting digital signals therealong;

timer means for producing at least one timer interrupt signal;

microprocessor means operatively connected to said memory means for loading and operating said algorithm, said microprocessor being operable to;

a) monitor said theft protection circuit and deliver a theft alarm signal to said serial port when the status of said theft circuit changes to a theft condition;

b) monitor said serial port for an incoming data dump signal and being responsive thereto to transmit the contents of said registers to said serial port and then resetting said registers, an incoming program reload signal to replace said algorithm with a new algorithm received at said serial port, and a data load signal for updating said thermostat configuration table;

c) monitor said occupant input means and being responsive to a temperature increase or decrease signal by comparing the request temperature change against predetermined temperature limits in said configuration table and, if the request change is within said limits, to generate and deliver heating and/or cooling control signals to said output terminal bank whereby to cause said heating unit and/or said cooling unit to be activated or de-activated;

d) set said "maid in room" register when said second input means is activated;

e) set said "maid left" register when said third input means is activated;

f) set said "room inspected" register when said fourth input means is activated; and

g) respond to a timer interrupt signal by processing a peak load management algorithm and/or a cooling cycle algorithm;

at least one thermostat control device having a serial port in communication with said serial port of at least a predetermined number of said thermostats, memory means for storing a configuration table for each said thermostats of said predetermined number of said thermostats, the contents of said registers of said predetermined number of said thermostats, and an algorithm for controlling the operation of said thermostat control device, timer means for producing a timeout condition at predetermined time intervals, and microprocessor means operable under the control of said algorithm, said thermostat control device being operable to;

a) monitor said serial port and set a signal receive indicator when a signal is received thereat;

b) monitor said timer means for a timeout condition and activating a peak load management algorithm when said timeout condition is detected and activating any acceptable thermostat requests;

c) poll each said thermostats of said predetermined number of said thermostats for and recording changes in said registers and status conditions;

d) respond to a request for a data download command received at said serial port by transmitting a data load signal and fresh data to all or specified ones of said thermostats of said predetermined number of said thermostats; and

e) respond to a request for a program reload command by transmitting a program reload signal and a new program to all or specified ones of said thermostats of said predetermined number of said thermostats;

at least one master control device having a serial port in communication with the serial port of one or more of said thermostat control device, memory means for storing a configuration table for each said thermostats of said predetermined number of said thermostats, the contents of said registers of said predetermined number of said thermostats, and an algorithm for controlling the operation of said master control device, timer means for producing a timeout condition at predetermined time intervals, and microprocessor means operable under the control of said algorithm, said thermostat control device being operable to;

a) monitor said master control device serial port and set a signal receive indicator when a signal is received thereat;

b) poll each said thermostat control devices for and recording changes in said registers and status conditions;

c) respond to a request for a data download command received at said serial port by transmitting a data load signal and fresh data to all or specified ones of said thermostat control devices; and

d) respond to a request for a program reload command by transmitting a program reload signal and a new program to all or specified ones of said thermostat control devices; and

a central computer having a central processing unit, a display screen and a keyboard for communicating with a user, and a serial port connected to said serial port of each said master control devices, and memory means for storing an algorithm and having a system configuration table for storing user specified information respecting each said thermostats, said thermostat control devices and said master control devices, and timer means for producing timeout signals at predetermined intervals, said central computer being operable to continuously;

a) monitor said keyboard for a interrupt signal and responding to a user request; and

b) polling each said master control devices for a data dump therefrom, checking the data received from each said master control devices for changes therein, updating said memory means, said central computer being responsive to user specified data reload and program reload commands to cause updated data or program files to be transmitted to each said master control devices for retransmission to each said thermostat control devices and for further re-transmission to each said thermostats.