Demand controller is an electrical energy meter with a control function. These meters monitor the demand, usually at a 30 minute interval, and change the built-in relay status. These relays when connected to loads can switch on and off based on pre-configured demand settings.

These meters are suitable for computing fixed or sliding integration periods, the interval period may also vary. Non-essential loads are connected to meter relay outputs and priority is set for switching operations. This configuration comes into action whenever the demand exceeds the set limits. Demand side management is achieved to reduce stress on electrical networks. Demand controllers also meet the need for energy saving and load management in industries.