Repositioning lights on trailer lighting board - wiring advice?

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Chris152

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I bought one of these recently to attach to the back of our little dinghy:
https://www.amazon.co.uk/gp/product/B002FVP7SC/ref=ppx_od_dt_b_asin_title_s01?ie=UTF8&psc=1

Reading the regs, the lights aren't close enough to the width of our trailer, so they need moving further from centre. I have a longer wooden board that I'll attach the lighting board to, move the lights further toward the edges of the plastic lighting board, and place the triangles and fog light onto the wooden board.

That leaves inadequate lighting for the number plate (the light for the plate comes from the tail lights, a clear lens toward the plate). So I bought two of these, which I'll connect above the plate.
IMG_20240927_061105.jpg

Question - do I simply connect the red and the black wires to the red and black wires (the tail light bulb) here?
IMG_20240925_091754.jpg

And at the other side, does the red of the number plate bulb connect to the 2x red cables, and the black connect to the brown?
IMG_20240925_092008.jpg

I think the question is more about whether this will work in principle - will the number plate lights come on when the tail lights are on? I really don't get electrical circuits. But also I wanted to check the connections are as I've described.

Thanks, Chris
 
Can’t help with the wiring - I would just test it in place and see if it works.

My concern is will the lights you have purchased for the number plate show a white light horizontally to the rear?.It looks like the lens is not shrouded to ensure the illumination would only (in your case) be directed downwards. Just my observation - I wouldn’t wish for you to non-compliant.
 
Yes, your wiring assumptions appear to be correct.
I'll also second LambCrafter's concern that the lights you're planning to use will show too much white light to the rear - probably easy enough to fix with the application of a little black tape.
 
Thanks both.
I hadn't noticed that the white light would show - these were the cheapest lights I could find, obviously not very good! The plan is to only drive in daylight anyway, but since my lad will be driving I don't want to set him up for any points on his license. OK, I think the tape idea should work, if not I'll buy better lights in due course. I'll post a photo once all's sorted.
 
When you move the light sideways, why can you not move the number plate sideways as well so it stays in the same relative position to the light and is illuminated in the same way?

Is there a regulation that says the number plate must be central? I had a quick look and cannot find anything. Tipper lorries do not have a central real number plate.

I had a further look and cannot find anything that says that if non-central, the plate needs to be biased towards the offside (it looks like the nearside light on the board you have bought has the number plate light provision).
 
When you move the light sideways, why can you not move the number plate sideways as well so it stays in the same relative position to the light and is illuminated in the same way?

Is there a regulation that says the number plate must be central? I had a quick look and cannot find anything. Tipper lorries do not have a central real number plate.

I had a further look and cannot find anything that says that if non-central, the plate needs to be biased towards the offside (it looks like the nearside light on the board you have bought has the number plate light provision).
Both lights need to move away from centre toward the edges,* so if the plate moves to one side, only the light next to it will be lighting the plate - the light on the other side would now be too far away.

*The regulation says the lights have to be within 400 mm of the outer limits of the trailer.
 
An unrelated tip.

If you take the covers of your trailer board lights and smear grease on all the connections and bare wires it will last a very long time.

If you don't the cheapest of cheap chinesium wire will rust through in no time.
 
I'm amazed, all lights working! We need to make sure it's all weather-proof, and tape over the number plate lights to stop the white light heading backwards, but that's for the morning. Trailer driving tuition tomorrow, soon be in the water. :)

Thanks all, really appreciate your advice.
C

IMG_20240927_193617.jpg
 
Check the speed of indicators flashing in case you have a super ancient flasher relay that relies on a bimetal strip and not one using electronics.
Those used to blink faster when you connected extra light bulbs in parallel with the ones in the vehicle.

Shows you how long it is since I wired a trailer socket :)
 
Is there a regulation that says the number plate must be central? I had a quick look and cannot find anything. Tipper lorries do not have a central real number plate.
You will find that the only requirement is that the number plate must be clearly visible from behind and be illuminated at night so moving that would be a good idea to locate it next to the light.
 
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