5V Low Level Trigger Module: 0-2VDC relay is connected (ON), 3-5VDC relay is disconnected (OFF). 5V High Level Trigger Module: 3.3-5VDC relay is connected (ON), 0-2.5VDC relay is disconnected (OFF). 12V Low Level Trigger Module: 0-5VDC relay is connected (ON), 6-12VDC relay is disconnected (OFF).
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