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Ralph Mowery
 
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Default Technique: wire preparation for a terminal block


"Zak" wrote in message
...
Back to basics here guys.

I am referring to a terminal strip like this.
http://www.ledlight.dk/images/samlemuffe400x320.jpg
It may be 3 amp or 5 amp or something similar to that sort of low
capacity.

The wire may be anything from wire which is thinner than bell wire
up to approx 13 amp mains flex (1.5 mm^2).

-----------------------------------
The QUESTION is this .... If you were using a terminal strip to
connect some wires then how would you prepare the ends of the wire
going into the terminal strip? It seems that there are few
satisfactory ways.
-----------------------------------

You can just strip back the insulation, twist if multi stranded,
insert and screw down. However there is always a risk that some
of the multi strands might break if the screw is tightened too
much.

However if the wire is quite fine then you may have to fold the
are wire back on itself. Maybe do that several times. But that
does not come out cleanly unless the retaining screw is almost
taken out.

You can add thickness to a fine wire by soldering/tinning the end
of the wire before it goes in. But this adds a lot of fragility
because where the solder ends is the point where the wire is
likely to bend if it is moved around in use.

I've even seen people sticking in *insulated* wire and tightening
the screw until it met the copper. This could work rather nicely
but only if you can get the depth just right. It seems to me that
chance plays far too large a part here.

The way I would love to do it is to get some sort of crimping tool
and put a small brass collar over the wire and squeeze the collar
on securely. The brass would be tough enough to resist the screw
doing any real damage.

What do you find is the best?


Either just strip the wire and insert it or use some hollow pins on the end
of the wires.

http://www.chromate.com/AgentCatalog...ction%2020.pdf

And look on page 24 for them. YOu should also get their crimping tool.

I have seen and used thousands of the pins at work. Everything from a # 22
or so wire for a 4 to 20 ma circuit to larger wires.
Some RTDs came in (probably 200 or more) with the same type of connectors.
They had very small wire and were just put under the screws. On the other
side we used the hollow pins or just the bare wire under the screws.