A single role control card is a relay card that can be used with Arduino or other microcontrollers where the contacts can be controlled by 12V.
The microcontroller draws a current of 20mA during the trigger signal. It is frequently used in various hobby, industrial and robotics projects. 30VDC or 220VAC voltage can be switched to 10A with the energy. There are control LEDs for each role. The relays are triggered by logic 0 (0V). The NC, NO and COM legs are removed for each relay. Thus it can be used in short-circuit in case of trigger or open circuit in case of trigger.