Basic relay setup

Home / the12volt's Install Bay / Relays / Basic relay setup (

Topic Closed)

Welcome Guest :)

Members

Search

Register

Login

< Prev Topic Next Topic >

pointjg

Member - Posts: 5

Joined: July 05, 2006

Posted: July 05, 2006 at 10:39 AM / IP Logged

Hey guys,

I am making a fan switch for a LT1 Trans Am, the fans need to be grounded to turn on, and I am using a SPST rocker switch with a LED, meaning I cant retain LED functionality by just using a ground as the power-in. So my idea is to use a relay to convert/reverse the polarity... the switch in the off position however connects 'ground' and 'acc', meaning in the off position it would be giving the relay a ground signal. Would this cause any problems? (Im pretty new to relay setups).

Here is my idea for the setup:

When the computer turns on the fans automatically it will also send a ground signal back to the relay, what will happen then? Will the relay send a positive signal back to the switch? If so the switch would be in the off position, meaning it is connecting ground with the postive signal and they would arch.

This is why I want to use a diode, but should it be used between the switch and relay or the relay and car harness? What kind of diode should I be getting? 1 amp?

Thanks in advance.

Back to Top

pointjg

Member - Posts: 5

Joined: July 05, 2006

Posted: July 05, 2006 at 10:41 AM / IP Logged

Even though it should not make a difference, the car is a 1995 Pontiac Trans Am (LT1 - 5.7L).

Back to Top

Hoptup32

Copper - Posts: 87

Joined: December 25, 2004

Location: United States

Posted: July 05, 2006 at 8:02 PM / IP Logged

Your switch wiring is OK the way it is. Even with the rocker switch in the off position, the 'ground' to 'acc' path to the relay will not affect the relay in any way, since the relay is only activated by a "+" feed to terminal 86, as long as the relay is wired as you have it shown.

I don't think there' is a need for the diode either. Even if the computer sends a ground signal to the fans, if the rocker switch is off, then the ground path from the computer stops at relay terminal 87 and doesn't affect the relay. Even with the rocker switch on, when the computer sends a ground signal, the ground signal would branch to the fans and pass harmlessly thru the relay from terminal 87 to 30 as another secondary ground path.

Back to Top

pointjg

Member - Posts: 5

Joined: July 05, 2006

Posted: July 06, 2006 at 5:33 AM / IP Logged

Thank you Hoptup32! Just the information I was looking for :)

Back to Top

Sorry, you can NOT post a reply.
This topic is closed.

Printable version

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

Search the12volt.com

Follow the12volt.com

Disclaimer: *All information on this site ( the12volt.com ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.

Basic relay setup

Sorry, you can NOT post a reply.This topic is closed.

Sorry, you can NOT post a reply.
This topic is closed.