Programmable electronic real-time load controller providing demand limit control

An electronic controller for controlling the energization states of a plurality of electrical loads, said controller comprising:

• a plurality of load control circuits, each said load control circuit being adapted to be interconnected with a load, and having a load-on state when its load is to be on, and a load-off state when its load is to be off;
• clock means for determining real-time;
• sensor means for measuring the actual rate of power consumption by the plurality of electrical loads;
• set point selector means for selecting a set point representing a desired rate of power consumption by the plurality of electrical loads;
• event memory means for storing a time schedule for real-time control of the plurality of electrical loads;
• program memory means storing a set of program instructions;
• processing means responsive to said set of program instructions for:
• determining a desired real-time control output status for each load by:
• obtaining real-time from said clock means;
• obtaining said time schedule from said event memory means;
• and through comparison of said real-time with said time schedule, establishing an on state or an off state for each load, said on state representing a desired load-on state for the associated load control circuit and said off state representing a desired load-off state for the associated load control circuit;
• determining a desired demand limit control output status for each load by:
• obtaining said actual power rate from said sensor means;
• obtaining said set point from said set point selector means;
• determining a shed condition when said actual power rate equals or exceeds said set point, and determining a restore condition when said actual power rate is less than said set point;
• establishing a demand group of the plurality of electrical loads;
• transferring a load into said demand group upon occurrence of an on state for the load and transferring a load out of said demand group upon occurrence of an off state for the load;
• establishing a shed group and a restored group within said demand group, the loads within said shed group having a shed state representing a desired load-off state for the associated load control circuit and the loads within said restored group having a restored state representing a desired load-on state for the associated load control circuit;
• upon determination of said shed condition, transferring at least one load from said restored group to said shed group;
• and, upon determination of said restore condition, transferring at least one load from said shed group to said restored group;
• and,
• controlling the actual energization state of each load by, for each load in said demand group, placing said load control circuit for the load into said load-on state upon occurrence of said restored state for the load and into said load-off state upon occurrence of said shed state for the load, and, for each remaining load, placing said load control circuit for the load into said load-on state upon occurrence of said on state for the load and into said load-off state upon occurrence of said off state for the load.