Picking the right relay

Thread Starter

Tim Blevins

Joined May 27, 2016
4
I need a 12 volt DPDT relay. I am using it to reverse polarity on four electric actuators operating in unison. Maximum amp draw on the actuators wired parallel is 5 amps each under a heavy load. I think I need a relay that can handle a minimum of 20 amps @ 12 volts.

For Instance this description:
  • Coil Voltage: AC 12V;
  • Contact Capacity: AC 240V/10A, DC 24V/10A
  • Type: DPDT(2NO 2NC);
  • Pins: 8 Pin;
  • Mount Type: 35mm DIN Rail
My question is on contact capacity.
Contact Capacity: AC 240V/10A, DC 24V/10A

What should I be looking for here to be adequate for the 4 actuators?? DC 24V/40A ? Or More ?
I just need an adequate relay with socket that will mount on a DIN rail to operate the 4 actuators.
The one above has been working adequately but I feel it may not be durable enough
Any suggestion would be great.
Thanks

https://drive.google.com/file/d/0B_auNJuo7alIZ2liRHJNOVhLMjg/view?usp=sharing
 

marcf

Joined Dec 29, 2014
260
You may want to inspect your attached schematic diagram. It appears that when the relay is activated, a short will exist across the battery.

Also, you may want to use the 'standard' schematic symbol for a DPDT relay.

The actuators, being inductive should have a suppression diode across them, as should the relay coil.

Also it is a good idea to connect the load across the C(ommon) contacts and the Power source to the NO NC contacts.
 
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