For automation of dg sets, power house offers solid state, single card, compact, and easy to operate auto mains failure [amf] relay. Following are some technical features of this amf relay which include: monitors main supply voltage, transfer of load on dg set and vice versa, auto stop of dg set and other allied functions automatically; has built-in three-phase voltage monitor, time delay circuits, starting attempts on and off delay timers, counters, failure indicators, logic controllers, stop solenoid, fuel solenoid, and timers. This single card relay replaces an array of different timers, monitors, contactors and problems associated with interconnection and loose connections. With optocoupler isolators for all high voltage incoming supply, and electromechanical relays for output connection made with matching electronics circuitry make it reliable and unaffected by any spikes and unwanted signals. Amf relay is for control part only and is suitable for a wide range of dg sets irrespective of kva rating of dg sets. For load handling at different levels, suitable relays, and load contactors are to be incorporated to match different engine/load characteristics.
