Arduino Forum

Using Arduino => Project Guidance => Topic started by: just4plaay on Dec 10, 2012, 03:54 am

Title: 16 Channel 12v Relay Module and Arduino
Post by: just4plaay on Dec 10, 2012, 03:54 am
Can someone help me with this relay module? I though it took a 12v power supply to the screw terminals but what I don't get is it has 5v and ground on either end of the 16 low level input pins. Obviously the arduino pins need to be connected to 1 - 16 but does it need ground and 5v power as well? Should the arduino be sinking or sourcing power?
Title: Re: 16 Channel 12v Relay Module and Arduino
Post by: johnwasser on Dec 10, 2012, 04:01 am
At a minimum it will need Ground.

The 5V pins may be there to supply 5V to the Arduino.  Does the relay board have a 5V regulator?  You'll probably have to find the schematic diagram of the relay board to determine that.
Title: Re: 16 Channel 12v Relay Module and Arduino
Post by: rikitheshadow on Dec 10, 2012, 07:57 am
The 5v there is an input, not an output. It needs the 5v to control the low level logic circuits on the relay board otherwise the arduino would send it commands, but none of the relays would trigger.
Title: Re: 16 Channel 12v Relay Module and Arduino
Post by: johnwasser on Dec 10, 2012, 03:37 pm

The 5v there is an input, not an output. It needs the 5v to control the low level logic circuits on the relay board otherwise the arduino would send it commands, but none of the relays would trigger.


I see now.  The 5V supply is needed for the opto-isolators.