Adding led lights...relay or not

[oldpilgrim]

I wouldn't be surprised if the relay drew more power than the led lights.

 

[TomSeller]

I wouldn't be surprised if the relay drew more power than the led lights.

If it did, the wrong relay was selected.

 

[jcummins]

If it did, the wrong relay was selected.

So relays are not all the same? Educate me on the relay I should use.

I'll actually tap to the back of the headlight switch since they go off when the key does, and it will be right beside each other.

 

[MF283]

Keep the answers coming folks, want to add lights to the new 550 & this thread is greatly appreciated, thanks jcummins for starting it. BTW, i hate fooling with electronics, so the easiest way to do this is....................

Ronnie

 

[Garandman]

Many motorcycles run 12V lighting directly through the switch. PILOON nailed it.

I ran mine through the work light circuit, switched directly for one 36W light.

 

[jcummins]

Here is the switch I'm using. It's a 20amp switch.
Amazon.com: E Support Car Blue LED Bar Light Toggle Switch: Automotive

The reason I've asked these question in the first place, I can't clearly understand how many amps these lights draw.
Adding a relay actually could man the install cleaner, wires are going to route right past the battery. So relay needed are not, fairly easy to do. But it adds cost.

Anyone clarify the amps these things will draw?

 

[Wild Bill the 2nd]

Watts / Volts = Amps
72 / 12 = 6
36 / 12 = 3

So with all of the lights you are looking at you will only be at 12 amps. The switch will handle it just fine. Now the trick will be finding a circuit on the vehicle that will handle the extra draw.
I like to take the draw back to the fuse box where you might be able to tap into an empty lug on the switched side of the box. Mind you, I'm not tapping into a fused circuit, I'm going to the main bus bar. The new line needs an in-line fuse.

I used these switches on my tractor light install. I had to go to the fuse box with the front lights as they drew nearly 25 amps. For the rear lights I tapped into the existing wiring since they only drew 3 amps.

 

[aczlan]

Here is the switch I'm using. It's a 20amp switch.
Amazon.com: E Support Car Blue LED Bar Light Toggle Switch: Automotive

The reason I've asked these question in the first place, I can't clearly understand how many amps these lights draw.
Adding a relay actually could man the install cleaner, wires are going to route right past the battery. So relay needed are not, fairly easy to do. But it adds cost.

Anyone clarify the amps these things will draw?

You don't need a relay to protect that switch, it will be fine running the lights directly. The relay is to protect your ignition switch so you don't melt it or start blowing fuses (if you are still pulling power from your ignition switch).

Aaron Z

 

[davesl708]

These lights not like days of old. They really don't draw many amps.

BUT I don't see in any of the documentation at Amazon exactly what they do draw. No further documentation came with the lights.

To determine the amp draw divide the watts by the voltage. Example my 18 watt Cree lights should draw no more than 1.5 amp. Actual amp test showed .7 amp draw.

 

[TomSeller]

This is would be how I would do it. The relay is just like your solenoid on your starter (the "solenoid" is a "relay"), it carries the heavier current. I would put the relay under the dash. The idea is that the added LED circuit would not draw power from the key switch itself. If your LED or the WIRING going to it shorts out, you don't want the key switch to carry that load (expensive to fix if that circuit's fuse is oversized). The wire going up on the ROPs or where ever likely is exposed to tree limbs or whatever hitting it and shorting it to your negative frame.