Geeetech

Also when you say low level and high level, do you have a specific voltage and current in mind? At what point is low level and what point is high?

I need more clarafication of Pin S, which is not marked on the diagram. Please specify input 1 2 3 as well, which is 5v which is common ground and what is the third pin for.

Chinduino 5V Relay module issue

applied 5v through the 3 pin cable relay led lit up and hear the trigger sound. However the screw down connection remain open circuit nothing happened. Closed circuit never occured datasheet unavailible online therefore assume circuit defective.