Catalog > Consumer Electronics > Kits > Various Kits High/Low Level Triger Relay Module High/Low Level Triger Relay Module BDD RELAY BOARD 2CH 3.3V 3,3V 2 Channel High/Low Level Triger Relay Module with Optocoupler 58.48 ZAR inc for 1 Each 0 in Stock Add Specifications, Prices & Availability may change without notice. Images are for illustration purposes only. E&OE Features Fault-tolerant design, even if the control line is broken, the relaay will not move; Specifications Module interface: DC+: Connect to the positive pole of the power supply (voltage is relay 3.3V) DC-: Connect to the negative pole of the power supply IN: The relay can be controlled by high or low level Relay output: NO: Relay normally open interface, before the relay is vacant, it will be shorted to COM after picking up COM: Relay Common Interface NC: Normally closed relay interface. Before the relay is closed, it is short-circuited with COM. High and low level trigger selection: S1 is the high and low level trigger selection of relay 1; When com is shorted to low, the corresponding relay is a low level trigger. When com is shorted to high, it is a high level trigger