I have tried all three methods and find they all have issues - maybe user error but nothing is worse than a failed connection behind an installed ceiling panel! The problem is that some puck lights are not 16 or 18 gauge but closer to 22. There is NO WAY the three way, butt connector or Wago can grip them well. So my approach is an old school screwed terminal block - more British style than US but works well and as a bonus is fully removable. These comes in various styles and can handle up to 20A 12 gauge. One example shown here:

Amazon.com

 

Yes these cover a wide range of gauge. Do you cover them somehow to avoid humidity? Does vibration loosen the screws?

 

Wire nuts

 

I've used wire nuts for all my vehicle electrical connections and have never had a connection fail. Use the proper size nut and check the connection by giving each conductor a tug and you should be fine.

I definitely don't like making connections that will be hidden behind walls with no way to repair if necessary. Our Acegoo LED puck lights have springs that hold the lights in the ceiling and they are quite easy to remove if necessary.

 

I think the key is to avoid puck lights and use LED strip lights.

That eliminates a large number of the issues of having a lot of connections like you are describing behind a wall / ceiling.

I won't put them in for customers anymore. Even if I can make essentially perfect crimps, so many of those pucks and the dimmers are junk and it is very difficult to protect those tiny wires from failure. Have I done it - yes and it works but it was a royal pain.

I did it using crimp connectors and heat shrink with the heat activated glue inside.

Most of the dimmers for puck lights on the market are junk. Before you put anything in the van - consider to first wire it up on a table to make sure that it all works.

 

I have used these Wago 221-613's, good to 10AWG. I put a Wago in my vice then grabbed the wire with pliers and twisted, pulled, levered and could not pull the wire free.

 

Posi-Tap products are a very good way to accommodate different wire sizes.

 

Any experience with the Modtek brand? Used for landscaping.

 

No experience with those, but they look great actually. Sort of like a Posi-Tap with gold plating on the contracts.

I've been using Posi-Taps for years, and quit using those cheap, clamping blade-type things a long time ago. Just got tired of wiring harness repairs from previous owner installations with those silly things.

 

Had never seen those Modteks, gonna pick some up for my yard lights. Thanks !

 

Crimp on wire splicing connectors McMaster-Carr

 

Hi,
Wire nuts are good for joining multiple wires of different gauges (and lots of other things).

For some reason, wirenuts have gotten a bad name, but in reality they work very well.
Twist them very tight and they will never come off.

I have tested the wire pull out strength for wires in wire nuts and they have better pull out strength that the Wagos that every one seems to love.

The idea that a properly tightened wire nut could come undone due to vibration is nonsense.

Gary

 

For some reason, wirenuts have gotten a bad name, but in reality they work very well.
Twist them very tight and they will never come off.

I agree that wire nuts will do the job, but I won't use them in vehicles. I think they look unprofessional, they're bulky, hard to seal and weather proof. They were originally designed and tested for solid core stationary wires. I think they have been approved for stranded wire in some applications.
In industrial uses I make sure wire nut connections are secured so they (and the wires to them) won't be subject to vibration/shaking. That's standard in machine applications.
I don't like to see them in vehicles. I still see twisted, sometime soldered, and taped connections in vehicles. It makes me question the quality of any other work the person has done.

I have tested the wire pull out strength for wires in wire nuts and they have better pull out strength that the Wagos that every one seems to love.

If pull out is a problem then the installer should stop all work (be fired?) and learn about strain relief. In a proper installation wire connections should never, ever be "pulled on". Use a longer piece of wire. Drill a hole and zip tie it or clamp it.

The idea that a properly tightened wire nut could come undone due to vibration is nonsense.

Failures I have seen are broken wires entering the wire nut that were scored by overzealous stripping (they can/will break from vibration) and wires that have come out because not all the wires ended up at the same depth in the wire nut.

 

When someone tells me they have some kind of electrical problem and then I see something like this (pic), I just want to close the hood and walk away. That probably isn't the only issue.

not my picture

 

If you want total reliability solder the connections and use heat shrink to insulate the connection. Of course you must know how to solder correctly. You can cover the connection with heat shrink tubing.
If not that then wire nuts are good too but also need to be done correctly.
Give every connection the 30lb. pound pull test. They must be mechanically secure as well as electrically.
Crimped connections can be difficult with different gauges and they fail the pull test the most often in my experience.

Hi,
If soldering, use a western union splice to connect the wires mechanically, and then solder and then shink tubing.

Google or Youtube for the western union splice.

Gary

 

duplicate deleted.

 

Outside of printed circuit board assemblies (control modules, displays, sensors, etc.) or on electromechanical device terminals (motors, solenoids, etc.), you'll find very few OEM soldered connections in vehicles or aircraft. And wiring harnesses and connector housings will always contain crimped connections.

In a static situation (no movement) soldering a wire joint should be superior to crimping. But in a movement/vibration application, it takes very consistent soldering skills and proper strain relief beyond the ends of the soldered connection to match the reliability of a good crimp connection. That's because the copper near the soldered joint will acquire some brittleness, and will be less able to endure movement.

Soldering entails too much reliance on individual skills and takes too much time for OEMs, and is largely beyond the resources of most end customers. Crimping is is quite easy for a DIY to be good and consistent with. Soldering can be better, but takes more time (and steps), and is more difficult to do correctly for the mainstream.

 

Hi DIYTech,
I respect your skills and experience in this area, but I've done many dozens of connections that use a western union splice that is soldered together and then covered with heat shrink tubing. They seem totally bomb proof and the idea that they could vibrate apart in the relatively mild vibration environment of a camper van just just seems way way way out there. If I want something that I know will hold up forever, the soldered western union is what I go to.

It seems likely to me that crimps are used because they are fast with low labor while solder takes a lot longer and a little more skill.

Gary

 

I soldered so much stuff as an EE student that I might never want to do it again (or course human soldered connections in electronics are all but obsolete anyway). But I will not solder anything in a vehicle (boat, automobile, or aircraft) because of the hardening of the joint.

A proper (not made with a $3 multi crimp tool from Autozone) crimp is far superior to a soldered connection in anything that can ever move. I prefer a ratcheting crimper for the small (10 gauge and smaller) stuff, a long handled crimper (at least a foot) for 2-8 gauge, and a hydraulic crimper for anything smaller than 2 gauge. When you crimp it right you are mechanically bonding the connectors in a way that is superior to anything else.

A lot of people do it poorly and that is why crimping gets a bad rep. If you can pull out the connection and still see individual strands it was never crimped right to begin with. They should be mechanically welded by the proper application of force.

 

They should be mechanically welded by the proper application of force.

Here is a crimp I cut open, 2awg.