Wire connections?

[Pub911]

So if you absolutely HAVE to put a splice in a 12v circuit, what's the best way to ensure a reliable, long-lasting, easy-to-diagnose-when-it-fails connection?

Butt connectors hide potential corrosion. So can shrinkwrap, but is that OK because they're supposedly vaport tight? Anyone vote for easy-to-view terminal blocks with crimped-on ring-type connectors? Solder? Or are there other answers? And what due the authorities say (ABYC?)

Thoughts?

[btrayfors]

Depends on the circuit and conditions, of course, but in many cases you can use a high-quality butt splice with adhesive heat shrink.

I use 3M heat-shrink connectors (both for butt splices and ring terminals) AND I often use heavy wall adhesive-lined heat shrink in addition. The result is a water tight, vapor-proof, physically secure connection which should last a very long time.

Crimping, by the way, should only be done with a proper tool designed for heat-shrink connectors, so as not to damage the heat shrink. Ancor makes one like this: CRIMPER TOOL MULTI-TERM FOR HEAT SHRINK 159418

Also, a new one by Kimball Midwest is designed specifically for heat-shrink crimp connections: Crimper handles 22-18, 16-14, 12-10, and 8 ga terminals., Kimball-Midwest

Bill

[mitiempo]

I would use a butt splice with adhesive heat shrink. To solder creates a hard spot where fatigue may eventually break the wire. Not to steal his thunder, but Mainesail tells how-to with pictures and reasons here All About Marine Wire Termination Photo Gallery by Maine Sailing at pbase.com (thanks Mainesail)

[sailingdog]

Heat shrink tubing is not vapor tight unless it is ADHESIVE LINED...

[btrayfors]

Yep, that's what I'm talkin' about. 3M adhesive-lined heat shrink connectors PLUS double-wall adhesive-lined heat shrink tubing OVER them.

Double-whammy. Ain't nothin' getting thru that stuff :-)

Bill

[Ashbel]

mitiempo

"To solder creates a hard spot where fatigue may eventually break the wire."

Not to re-open the solder vs crimp debate, as it has been beaten to death many times on this forum and others, I just wanted to point out a common misconception about the various types of wire / terminal connections. What most people don’t realize and is rarely mentioned, is that ALL connections, soldered, crimped, produce a point of fatigue were the wire effectively goes from flexible strands to a solid mass. That is the goal of a good connection. The issue isn’t whether or not a hard point is created (they all create them), it is controlling where it is created and how it is supported. A correctly made and insulated soldered connection is very effective and long lasting. The problem is the average person doesn’t have the training or skills to produce them.

Another misconception is that ABYC code does not allow the use of soldered connections. Not true, the code states solder may not be used as the sole form of connection. But it may still be used. As an example, a wire loosely inserted into a terminal (but not crimped) and soldered would be using solder as a sole source of connection. Meaning if the connection heated up enough to melt the solder the wire is free to disconnect from the terminal. Not good. However, if that same wire was crimped into that terminal and then soldered that is OK. The first thing I was taught about soldered connections is that you need to make a good mechanical connection first.

When I used to make my living fixing helicopters, 9 out of 10 times when there was an electrical problem it could be traced to a fractured wire conductor where it exits a crimp terminal. So my personal experience tells me that crimp connections can have fatigue / fracture issues too.

But with all that said, I agree with the majority, use high quality adhesive shrink type crimps and a high quality crimp tool. Most people will get the best and most consistent results using that method, which is one of the reasons they are so commonly used. Mainesail does an excellent job of describing what is and isn’t a good crimp and tool.

My apologies for long reply.
Mark

[funsailthekeys]

Why would you use butt connectors on a new install?

[thekeip]

I very often use appropriately sized barrier strips and ring terminals instead of butt splices. A good example might be for connecting mast wiring for lights or instrumentation. Splicing just isn't an option.
Howard Keiper
Berkeley

[justified]

there are available butt connectors that have dielectric greese on the inside which coats and seals the splice. I get them thru my brother-in-law who is an electronic engineer. you might want to check radio shack or other electric supply houses.

Peter
"Justified"

[Maine Sail]

Properly executed butt splices are strong, very, very strong (see photo).

This Crimp:

Held all four of these anchors:



Even adhesive lined heat shrink alone has a decent grip!


This was heat shrunk only and NOT crimped:

It held a fairly decent load even without being crimped: