Wire connections

[zeitgeist]

I am doing some 12 VDC wiring on the trailer hitch / towed vehicle of the motor home and was curious what others preferred. These connections will be exposed to weather. 

Optional questions:  Do you use dielectric?  Shrink tube?
                           

[Chris_]

I use butt connectors and shrink tube for ease of use, but I like to live dangerously.

I think the optimal method would be solder and shrink tube.

[BattleHymn]

Assuming you want to keep it permanent, I'd use a solder splice.  Then, I'd slap some shrink tube around the splice.

[Chris_]

I can't imagine using wire nuts outdoors.  Those are the kinds of cars you see on the side of the road with flames coming out of them.

[BattleHymn]

I can't imagine using wire nuts outdoors.  Those are the kinds of cars you see on the side of the road with flames coming out of them.

I've been there, but not because of a wire nut. 


Surprisingly, it was a British car. 

[thundley4]

I go for over kill, soldered butt connector wrapped with tape then shrink tubing.

[DLR Pyro]

I go for over kill, soldered butt connector wrapped with tape then shrink tubing.

Id do the same but also add some dilectric grease to the soldered joint before slipping the heat shrink tubing over it.

[Chris_]

Id do the same but also add some dilectric grease to the soldered joint before slipping the heat shrink tubing over it.

I guess I'm not familiar with dielectric grease.  What does it do?

I remember reading a story about a car magazine that was test-driving a Jeep 4x4 diesel a few years ago.  During a routine service, one of the mechanics got some dielectric grease on one sensor or another and the engine would randomly quit.  It got to the point that Chrysler flew some eggheads to wherever this magazine was located to go over the truck with a fine-tooth comb.  They finally found the messy culprit and cleaned it up.

[MrsSmith]

http://www.absoluteaquatics.com/products/Silicone-Wire-Nuts.html

I would look for something similar to these.  I picked some similar ones up at Lowe's a couple weeks ago, but they were for much higher voltage.  The silicone seals them up pretty tight, as far as I could tell.

[Wineslob]

Assuming you want to keep it permanent, I'd use a solder splice.  Then, I'd slap some shrink tube around the splice.

+1

[TVDOC]

You have a good consensus above, but the best connection if expoed to the elements is a solder splice covered with self-sealing shrink tubing.......this type of tubing has a sealant that melts when the heat is applied to shrink it, and forms a permanent watertight connection.  It's also available for connections that are buried.....the phone company uses it all the time in splice boxes (although they use crimp connectors, but since the splice is air and watertight, they are fine), and it's commonly available from any good electronic outlet.....or even online at DigiKey.

doc

[Janice]

How about liquid electrical tape? And whats the best/ cheap type of electrical connector for dc trailer wiring?

[TVDOC]

How about liquid electrical tape? And whats the best/ cheap type of electrical connector for dc trailer wiring?

Never used liquid electrical tape, but I'd consider it less than a professional approach.

For connections inside a trailer, crimp butt connectors are fine, particularly when used with stranded wire.

doc

[zeitgeist]

THANKS to all for the great replies.   I will be going with a solder splice with shrink tube.

I will have to look at the connectors Mrs Smith mentioned.  I think they may be what the truck place used on my stop / tail lights last year when there was a problem during inspection.  They said they had to replace a couple butt connectors that were brittle.
 

Posted by: MrsSmith 
Insert Quote
http://www.absoluteaquati...s/Silicone-Wire-Nuts.html
 

As a side note I have determined diesel pushers are dirty as the dickens to work on. 

[BattleHymn]

You have a good consensus above, but the best connection if expoed to the elements is a solder splice covered with self-sealing shrink tubing.......this type of tubing has a sealant that melts when the heat is applied to shrink it, and forms a permanent watertight connection.  It's also available for connections that are buried.....the phone company uses it all the time in splice boxes (although they use crimp connectors, but since the splice is air and watertight, they are fine), and it's commonly available from any good electronic outlet.....or even online at DigiKey.

doc

OK, I am going to look for some of this for a project.  I'm guessing the right item is any tubing listed as "adhesive lined"? 

[Chris_]

I'll need some of that as well.  I have to splice in a couple of wires to finish repairing the wiring harness on my Datsun.

[zeitgeist]

The wiring job is finished and tested out fine.  I used a long splice, silver soldered, shrink wrapped, and then taped. Soldering outdoors was a bit of a challenge but I managed to get 'er done.  I will have to get some of the shrink wrap TVDoc mentioned.

I also used dielectric on all spade connections.   

[TVDOC]

The wiring job is finished and tested out fine.  I used a long splice, silver soldered, shrink wrapped, and then taped. Soldering outdoors was a bit of a challenge but I managed to get 'er done.  I will have to get some of the shrink wrap TVDoc mentioned.

I also used dielectric on all spade connections.  

If you can't find it, completing the solder connection, coating it (lightly) with silicone sealant, sliding the shrink tubing over the silicone covered wire splice, shrinking the tubing and wiping off the excess sealant, works just as well.....

The "self-sealing" shrink tubing is simply coated internally during manufacture with a heat-activated form of silicone sealer.

NOTE:  For weather exposed connections always use black (or opaque colored) shrink tubing (not clear) for UV protection......the "clear" shrink tubing will deteriorate with enough exposure to sunlight.  The same rule applies to tie wraps (plastic ratchet type wire ties) never use the white ones for exterior jobs.

doc

[Thor]

Soldering, assuming you know how to do a telephone splice, is the best. The self sealing heat shrink would be the best "sealer/weatherproofer". Since that's not readily available, I have used RTV sealant to coat the exposed splice, slid the regular heat shrink over it and shrank it down. Need to be careful on the type of RTV sealant one uses because the ones with acetic acid are know to cause corrosion. (In Accordance with the Navy's "509" & "540" manuals.) I use Dow Corning RTV 3145, when I can find it. If not, some of the copper sealants sold at the automotive stores have less acetic acid in them.

The "509" manual is for aircraft corrosion control and the "540" manual is for avionics corrosion control.

[Thor]

The wiring job is finished and tested out fine.  I used a long splice, silver soldered, shrink wrapped, and then taped. Soldering outdoors was a bit of a challenge but I managed to get 'er done.  I will have to get some of the shrink wrap TVDoc mentioned.

I also used dielectric on all spade connections.   

silver soldering is a waste. I use 63/37 lead/tin solder for all of my electrical connections whenever possible.

[Thor]

How about liquid electrical tape? And whats the best/ cheap type of electrical connector for dc trailer wiring?

Liquid electrical tape is used by the micro-miniature component repair folks in the Navy for certain things. It doesn't seem to withstand a lot of wear & tear, though. I wouldn't recommend it.

As far as trailer wiring kits, pretty much all of them are the same any more. I just use the ones from Walmart. They work as well as any other.