Go Down

Topic: Wiring a Opto-Isolated Relay to Arduino (Read 18254 times) previous topic - next topic


If you want complete isolation,  you will have seperate 5V supplies, one for the Arduino and one for the relay power.

Then you would connect an arduino output pin to the cathode of the drive LED, with VCC to a current limit resistor to that anode.

On the other side, you have pin 1 of the jumper field goes to the pin that goes to Pin 4 of the optoisolator.

If you  only have 1 wallwart, leave the jumper in. Having an optoisolatar and the relay seems like overkill to me. Most applications just drive the transistor to drive the relay.
Yes, use seperate 5V supplies, do they need a common ground?

Go Up