Electricity failure alarm using micro controller and #ZCD: The #circuit given here gives audio-visual indication of electricity failure. It operates on battery. It uses 20 pin micro controller AT89C4051 and it gives audio alarm as well as LED indication whenever electricity fails. It uses ZCD (Zero cross detector) circuit to generate 50 Hz pulses out of 230 V AC mains. | EngineersGarage

design problem there are four hazard inputs to an alarm system that goes on as some of operation malfunction occurs the system operates as follows if one input is on nothing happened if at l 26996

Fix Code C0800: Problematic Control Module Power Circuit