I trying to control my turntable switch with Arduino. This is a toggle switch with 3 wires one wire is for CW rotation the other one is for CCW and the other cable is main with 240VAC. I am using this relay http://www.seeedstudio.com/wiki/Relay_Shield_V2.0 from this shield I am using two relays with this this connection idea:
So basically one relay is controlling on/off and the other relay will control rotation in CW and CCW. For now I have tried this connection with two 12V LEDs and it's working fine. But now that I need to use my turntable, I think I should connect common of first relay with the main of 240V AC and I am not sure if I can do this or not (how safe it is).
Do not connect your arduino so it connects to a live power-line
Which relay ?
Sorry for the image I have updated my first post. But what do you mean do not connect Arduino?
Keep high voltage AC to COM and NO/NC connectors. They are electrically separate from Arduinos power, so this is safe.
(I was arfraid COM may be a referance to GND, which the schematic shows is not the case)
Just the way the stock wiring is to the switch, gos to the relays.
You shouldn't feed mains into the COM terminal and then only use one of NO and NC,
since that leaves the unused terminal live at times.
Mains in to NO, out of COM, NC will never be connected to the live directly. Then feed
the switched mains to COM of the direction relay. All mains connections should be
shrouded (such as with heat-shrink or rubber sleeving) so that nothing live can be
touched even with the case off.
The relays must of course be mains rated and capable of driving the load (is it