Relay Module Interface Boards for Arduino Low Level Trigger 1/2/4/6/8 Channels

Input IN1, IN2, IN3, IN4, the signal line LOW effective. IN1-IN8: trigger signal, active low. NC1 - NC8: normally closed relay interface relay shorted with COM ago, after the pull- vacant. Relay outputs : a 12- line interface, the interface can be directly connected to all leads, user-friendly.

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