Joining broken wire

Extend the wires. Part of the problem is caused by the lack of slack. Far better to put an extra length in to allow you to make proper connections than do a half assed job that lasts 5 minutes.

Dave Plowman (News) pretended :

I agree.

Well almost.

The problem is the plastic buffers the action of the crimp die. The uninsulated crimps work fine.

Unfortunately, you snipped this:

"In the early sixties I spent some time persuading my employers that crimped connections were the way to go, over and above other forms of termination. I was helped in my quest by an employee of A-MP, who had lots of photographs and other technical data showing that a properly made crimp, used within the range of cable sizes, actually "cold-welds" the wire to the lug."

As we were discussing pre-insulated crimps, I felt I didn't need to mention that those were what I was talking about.

Regardless of what you think the crimp you have made looks like, I can assure you absolutely that the scientific studies done on this method of termination has proved beyond doubt that this is the most reliable way of doing things, and has been for over 40 years.

Chris

Chris Whelan laid this down on his screen :

We will have to agree to disagree. They do seem fine for jointing solid wires, but in my experience not so good for jointing flexibles.

Most uninsulated crimps are sort of heart shaped. You can't do that with an pre-insulated type.

Hence why edac connectors are so much more reliable than ddks.

How did you persuade them to fail?

Can you give a link to one of those - specifically and only for the red blue and yellow pre-insulated crimps?

Because they're made in such vast quantities compared to other crimp tools (most electricians will have one) they shouldn't cost more than perhaps 30 quid for the very best.

As i said you pays your money and takes your choice , cheaper units ideal for site sparks generally using only solid core wires , the best units suitable for both applications.

Same with multitmeters , i have two one i use on site cost me £40.00 the other i use for electronics which cost £400.00 , the former is fine for site the latter will do both but to a far higher accuracy

So give me an example of the best unit? I've not been able to find one over 40 quid. Of course you can get some types that accept a variety of jaws - but I'm not talking about those.

A decent test meter for site use is likely to cost more than an electronics one. It needs to measure things like earth loop impedance and insulation leakage, etc. An electronics DVM can't do these. Even my Fluke. Which DVM do you have that cost 400 quid?

I paid less for the site tester than the 867B. The T5-600's rather more used though.

That argument can be applied to almost any ratchet crimp tool, that's th= e =

specified crimp tool for AMP plastigrip terminals, I don't think I've =

actually seen it used for anything else.

Check out RS £104 plus

I am not talking about impedance or leakage test meters etc which can run into 4 figures with toys just a plain multimeter .

I have a cheap clarke multimeter £40.00 used on site , idiot (Apprentice) proof , a fluke 117 calibrated £220 ( faulty apprentice dropped it ) and a fluke 289 calibrated £450 that i use at home for hobby electronics and work when needed

I used to have a bench multimeter that cost £4000.00 new , that was left by a defunct company along with colour screen oscilloscopes and other gadgetry in a store cupboard .They had obvously been deliberatly hidden because they had been boarded in .

Plenty of ratchet crimp tools available for pre-insulated crimps only - you'll find them in near any electrical wholesaler for around 15 quid.

What's your point?

Duncan Wood explained on 16/02/2010 :

I don't. I have seen many used on flexible, where wire strands have parted.

I've seen many solder joints that have fallen apart or the wires have broken.