Using relay with 230 volt AC source and 12 volt DC shared.

Hi all,

I want to control a 230 volt igniter with a my arduino. When i set PIN8 high, the Igniter should start. I also want to start a DC motor. Is it ok to connect the DC motor like the drawing shows?

Drawing can be seen here: http://billedeupload.dk/images/yIcX3.png

Apart from the invisible pic, nobody but you knows what "as expected" means.

  1. You cannot feed 12V to the Arduino Vin pin. You must use the power input of the board.

  2. You need a transistor to drive your relais (plus freewheel diode).

  3. You can use one relais, if the isolation between the two sets of contacts is designed for 400V or higher.

"1) You cannot feed 12V to the Arduino Vin pin. You must use the power input of the board."

Yes you can. Doing so merely bypasses the reverse polarity protection diode between the barrel jack and the Vin pin.

CrossRoads is RIGHT. I mixed it up vith the 5V pin. Sorry.