Adding underwater lights to SV211

[SG]

I replaced my speedo with a GPS speedo and am planning to pull off my old pitot pickups on the stern. I thought it would be a perfect place for underwater lights since there are already 2 holes drilled for the tubes. I was going to wire them to the courtesy light located ant the back of the walkthrough. I bought two 50 watt LED underwater lights. My question to you electrical engineers is do I need to add a fuse to the circuit or a bigger circuit breaker to the courtesy lights? Thanks!

[MLA]

I would not wire external lights to an interior light circuit. You would not like having the courtesy lights on while trying to enjoy the underwater lights. From a safety standpoint, that courtesy light circuit was not designed to support additional lights like underwater lights.

[MN Ryan]

I would agree that you won't want them wired with the courtesy lights. I'm betting your keypad/switch panel has an empty 12V switch--I know mine does. I would wire them to that switch so that you can control the underwater lights separately from the courtesy lights.

Yes, they should be fused. You'll need to know how many amps the lights draw. You'll also have to look into that 12V switch as I am betting it is on a breaker of it's own, and you'll want to make sure that it's of the proper amerage for the load the lights will put on it.

Alternatively, you could wire them separately and add your own switch, but be sure to add a fuse/breaker.

[SG]

Thanks,
I don’t have the shower option in my boat so I could use that switch. The lights are 50 watt at 12 volts so a little over 4 amps. Thanks for the input!

[ScrewPusher]

take some before and after pictures, this sounds neat and I like the idea of using the pitot tube holes.

[SG]

I will. I probably won’t do it until the end of the season since I have to pull the boat out of the water…

[Tigerxj]

from my experience in the jeeping world, I would recommend using a relay to power those lights, instead of running all the current through the dash switch. In the case of a relay, you are simply using a very tiny current through the switch to flip the relay, which gets its 12v power directly from the battery. Less chance of burning up the dash switch, safer, more reliable.

If you use a relay, you could jumper them off an existing circuit, rather than the courtesy lights, perhaps the nav lights, as I imagine you would probably be running with those on if you are going to have the underwater lights on at night.

[SG]

Thanks, that’s a good idea…

[MLA]

Before using the NAV light circuit, keep in mind that on many lakes, underwater lights on while underway, is a violation if they are any other color then white.

[MN Ryan]

I believe that displaying any lights at night other than your red/green nav and white anchor lights is technically illegal. That doesn't stop people from driving with their docking lights and color changing pontoon lights on.

[Tigerxj]

Yes, I suppose that would be an issue. I guess people use these underwater lights when anchored out somewhere? In which case if we are being sticklers, if anchored depending on location you should have an all around white anchor light. Can these nautiques turn on the white tower light and not turn on the red/green nav lights?

[MN Ryan]

Yes, you can (though I don't believe it is required to turn off the nav lights when anchored). If you have this style keypad, I believe that you hold down the nav/anchor light button for a few seconds to turn on just the anchor light.

Also, if you have docking lights, you turn them on by holding down the courtesy light button for a few seconds--it took me a while to figure that one out.

[TechBeer]

I would definitely run it through a relay like Tigerxj recommended. 50W is a LOT for LED lights. Is that 50W actual power or incandescent equivalents? For example, a 150W equivalent flood light only consumes 19W. If you truly have 2x 50W bulbs that you are wiring in parallel (12V each) you're talking 8A of current (100W/12V = 8.3A). In that case you really need to think about the gauge wire you are using.

Let us know how you make out.