On Thu, 16 Mar 2006 20:47:37 GMT, Zak Gave us:

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).


No, the wire may NOT be in that range (thinner than bell wire). The
terminal strip you show has a minimum wire size acceptance as well as
a maximum.

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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.
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That should read "There are few satisfactory ways".

You can just strip back the insulation, twist if multi stranded,
insert and screw down.


If you strip it correctly, it will retain its original twist. Also,
shear cutting should be used, NOT some lame pinch type snips.

However there is always a risk that some
of the multi strands might break if the screw is tightened too
much.

Shouldn't be.

However if the wire is quite fine then you may have to fold the
are wire back on itself.

Bad practice, and likely that the wire is below the minimum spec for
the connector block.

Maybe do that several times. But that
does not come out cleanly unless the retaining screw is almost
taken out.

Bad practice. Should not be done... at all.

You can add thickness to a fine wire by soldering/tinning the end
of the wire before it goes in.

Such terminal strips are not meant to accept tinned ends of stranded
wires. That is out of spec.

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.

There is also a solder "creep" issue to worry about, and it is a
significant issue.

http://en.wikipedia.org/wiki/Creep

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 instance for having insulator in the screw to wire interface is
too high. This is another practice that should be avoided.

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.

Yes, brass creeps even less than copper, and far less than solder.
In this case, one MAY use a smaller than spec'd wire size as well.

The tin plated crimp section of a cut off ring terminal (minus any
insulation) would also be a good candidate for this procedure.


What do you find is the best?

The right size solid wire is a straight insertion and clamp. The
right size stranded wire with large gauge strands is a simple insert
and clamp as well. Finer strands works, but starts to lean toward
your last solution.

One should never apply a tinned stranded wire end in a screw clamp
type terminal due to creepage issues.