LUMEN ELECTRONICS INDIA has developed a universal SCR Trigger Unit Type 3021 for all type of SCR Firing system. This type of universal Trigger Unit can be mount directly on SCR module or on the heat sink. It is fully isolated from input to output.This unit is also direct replacement of TUCHENG Trigger Unit. The specification of the SCR Trigger Unit Type 3021 is as under. Input DC 12 Volt Output 220V AC 50HZ.