Input part
DC +: connected to positive power source (supply power according to the relay voltage)
DC -: connected to negative power source
CH1: 1-channel relay module signal triggering end (effective at high level)
CH2: 2-channel relay module signal triggering end (effective at high level)
CH3: 3-channel relay module signal triggering end (effective at high level)
CH4: 4-channel relay module signal triggering end (effective at high level)
CH5: 5-channel relay module signal triggering end (effective at high level)
CH6: 6-channel relay module signal triggering end (effective at high level)
CH7: 7-channel relay module signal triggering end (effective at high level)
CH8: 8-channel relay module signal triggering end (effective at high level)
More details can be found in WIKI.
