When to use relays to wiring off road lights and accessories?

When to use relays to wiring off road lights and accessories?

Whenever wiring off road lights, it’s important to add a relay to the wiring. Failure to do so would cause excessive heat in the wiring and switch and create a risk of fire. This is caused by the amount of power being drawn by the high output lights or accessories.

What is a relay and how does it work?

What is a Relay and How Does it Work? A relay is an electrically operated switch. They commonly use an electromagnet (coil) to operate their internal mechanical switching mechanism (contacts). When a relay contact is open, this will switch power ON for a circuit when the coil is activated.

Where can I find a relay for a light?

Relays can be found by the light and electrical part of the automotive sections. They’re real cheap and should never be overlooked. If you have any doubt about how much power an accessory will pull then add a relay. The first thing you have to do is determine the current you have to carry.

What kind of rating does a relay have?

Basic relays feature electrical ratings for both the coil and the internal switching contacts. The coil voltage rating is the voltage required for the coil to operate correctly. The switching circuit of the relay also features a voltage and ampere rating. This is the maximum rating of the switch contacts and should NOT be exceeded.

How are the lights connected to the relay?

If installing lights, split it into two leads at the lights. If you do this be sure the wire is rated to handle BOTH lights since it will carry the current of both. The diagram shows two leads coming from the relay. Then I run the second wire of the lights or other accessory to a good ground on the frame of the vehicle.

Do you need a switch to turn on a relay?

In almost every case where high current is required, the switch you will use to turn on the power should not handle the load because most switches are not designed to handle higher amps. The job of switching the power is better left to a relay. What is a relay? A relay is a device that, through a magnetic induction coil, turns on the power for you.

What kind of relay do I need for my 4×4?

The switch that is installed in the cab of your 4×4 actually only powers the relay itself which draws very little current. In most installations a 30 AMP relay from Radio Shack (Auto Relay Cat. Number 275-226) will do unless your amperage demands exceed 30 amps. I like to used a lighted switch in the cab to let me know if driving lights are on.

Where can I find a 12V relay wiring diagram?

Dozens of the most popular 12V relay wiring diagrams created for our site and members all in one place. If you need a relay diagram that is not included in the 76 relay wiring diagrams shown below, please search our forums or post a request for a new relay diagram in our Relay Forum.

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