The board uses a combination of main power terminals and smaller control pins for various functions:
Without the schematic, a technician is essentially working in the dark. The diagram provides:
JYMC-220B-I high-reliability SCR-based motor speed controller primarily designed for DC brushed motors in mini lathes, such as the
Next to the MCU, you will see a (labeled Y1). This is the heartbeat of the processor.
No output, but primary cap holds 340V DC.