Installing Backup Lights

[1L243]

I'm installing 18w LED backup lights that run 1.5 amps each for a total of 3amps. 14ga wire a distance of 30 feet. Do I need a relay?

[1L243]

Added backup lights to 2017 Coleman 300tq. I had already added marker lights to the bottom frame below the ramp door.
I found some nice surface mount Led's 18watt flood . I wanted surface mount because i did not want the lights hanging below the frame.
You will need a 7 Way wire harness on your truck and trailer. The center pin will be wired to the backup light on the truck.
On my trailer I only had 6 wires seen plus a metal residential type electrical box that was not waterproof. So I orderd a 7 Way 8' harness with junction box that is color coded.
I fused the yellow reverse light wire with a 5 amp fuse for a 3 amp draw. I did not run a relay.

The lights sit well on the bottom frame.


The lights are bright

Lights up the RV Port well

Cost
Lights $17 each
Harness with box $37
Wire $10
Fuse harness $5

[MEXICOWANDERER]

To me...

A correct back up light issues an extremely wide light pattern which is hard to get without a dispersion lens with LED. Look again at outdoor floodlight with LED chip. What I see above are automotive lamps.



https://www.ebay.com/itm/12V-DC-Waterproof-IP65-10-Watt-Outdoor-LED-Flood-Light-LED-Garden-Light-Lam...

This is a true flood lamp. I would angle them slightly splayed toward the outside. No you cannot read a newspaper at 100 yards but they are about 10 times as bright as any car backup lamp. Do not mount with cord facing up.

[DrewE]

1L243 wrote:

We have no DOT inspections in Oregon so I don't think there will be any legality issues...

Just because there are no inspections doesn't mean the lights would technically be legal unless DOT approved; you could still be issued a fix-it ticket or similar, the same as if you put green flashing headlight bulbs in your vehicle or whatever.

On a practical matter, that's not very likely unless the lights cause problems--they blind other drivers in parking lots when you back up, or they're on when you're traveling forward, or something like that. Most police officers have many, many better things to do than randomly checking people's back-up lights for technical compliance with legal standards.

[01tundra]

Linked below are the LED's that I used. Powered off the center pin of the 7-way plug with an inline fuse, no relay.

Trailer is approximately 20' long, used a 12 gauge outdoor extension cord with the ends cut off for the wiring.

Never have had any issues with them and they work great.

https://www.amazon.com/gp/product/B00IXDN0Y4/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

[MEXICOWANDERER]

Anyway...

If I may recommend...

Silicone dielectric grease.

When you mount the lamps

Smear dielectric grease liberally around the electrical cord entry

And force it as best you can between the clear lens and lamp housing. Similar to packing a wheel bearing.

It's an 83F day...

And my reading light has been on for a few hours.

The temperature of the lamp housing is right around 118F. I can touch it but not hold my finger to the housing. This thing really belongs out of doors.

It is NOwhere as bright as a 6-chip CREE LED square lamp.

[1L243]

I check the 1 star rating along with the other ratings. An overall rating of 4 out of 5 stars is not bad. It would be hard to find anything with no 1 star ratings.

[MEXICOWANDERER]

I ALWAYS check (1)-star reviews before purchasing. Good luck with yours 🙂

I won an eBay auction for a 6" 18 watt light. It was brand-less. And I found out it wasn't CREE, has no voltage regulator, no IP 67 waterproof rating and has a highly questionable value of $1.55 free shipping. But it sits over my head in bed on the wall as a reading light. The Lifeline is floated at 13.3 volts and this seems to suit my trashcan grade lamp.

I would urge ANYONE looking at these lights to ensure the ad clearly specifies CREE. There is one vendor a highly rated one that ships from CA / KY that has been ultra reliable. I submerged a handful of their lamps to the bottom of a plastic 55 gallon drum then forgot about them for a month. They came up as dry as a bone.

Again, best wishes. I have so far purchased in excess of 200 LED lamps and fixtures and learned quick!

[1L243]

I went with the Kawell 18W surface mount FLOOD lights. I did not want the lights hanging down below the bumper (or bottom of trailer)

You just don't know how bright they will be till you get them installed.

We have no DOT inspections in Oregon so I don't think there will be any legality issues...
https://www.amazon.com/KAWELL-10-30V-Waterproof-fishing-Driving/dp/B00NPQV06O/ref=sr_1_fkmr1_1?ie=UT...

I did find this youtube video
https://www.youtube.com/watch?v=O5lttt8j8Ys

[MEXICOWANDERER]

Look at the cones surrounding the tiny yellow CREE chips.
The ones on the left have concentric rings
The ones on the right do not

The ones on the left help make a lamp disperse light much wider and taller (flood light)

The ones on the right make the lamp illuminate much further distance. Spot light.

Can you guess which one would make a useful backup lamp and which one would would merely drill narrow thin holes in the black of night?

Backup lighting really deserves DISPERSION LENS which is frosted plastic sheeting but the stuff is hard to find. I became an Original Equipment Manufacturer for Lumilux because conventional CREE lamp design did not allow for wide dispersion.

Hope this helps...

[ScottG]

RoyB wrote:
I would check with the local DOT/DMV to see if your BACK-UP lights are the approved type. Here in Virginia we have a bunch of laws around this and in my case I ended up a couple of times having to remove things in front of the Safety Inspection bunch before they will put a Safety sticker on my trailer haha...

They certainly did not like my switchable back up lights - had to come on when my truck went into REVERSE... After I removed them then i mounted them on the rear side of the trailer and actually got better results looking back from the truck.

The Safety Bunch here really watches what goes on the back and front of the road vehicles and trailers (in my case) here...


Roy Ken

Thankfully (?) we have no such inspections here so we can do anything we like.
OTOH with no inspections, we have a lot of junker vehicles running around without working tail lights, etc.

[RoyB]

I would check with the local DOT/DMV to see if your BACK-UP lights are the approved type. Here in Virginia we have a bunch of laws around this and in my case I ended up a couple of times having to remove things in front of the Safety Inspection bunch before they will put a Safety sticker on my trailer haha...

They certainly did not like my switchable back up lights - had to come on when my truck went into REVERSE... After I removed them then i mounted them on the rear side of the trailer and actually got better results looking back from the truck.

The Safety Bunch here really watches what goes on the back and front of the road vehicles and trailers (in my case) here...


Roy Ken

[ScottG]

Retired EE here. For three amps I wouldn't (and didn't) use a relay for b/u lamps. As Mex indicated, even if there were a decent voltage drop the lights would be just as bright. But with 14awg wires you will not have any significant Vdrop.
Mine have been wired that way for at least 5 years and work great.

[enblethen]

I would use a relay. Power the contacts off the trailer battery(ies) and use the TV as the control.
Amperage seems high. What is make and model of proposed lights?

[MEXICOWANDERER]

Check that ad carefully. Many 18-watt lights are manufactured with CREE chips and they use a voltage regulator that allows the same brightness from 10-30 volts.

At 12.0 volts none of the dozens (not an exaggeration) that I purchased drew more than 1.1 amperes. The amperage is rated at 10 volts.

You will do fine with what you propose. I smudge a little silicone grease around the grommet for the wires.