Andrew Gabriel
wibbled on Monday 19 October 2009 13:35

In article ,
Tim W writes:

In principle it sounds fine. Crimps would be an excellent way to joint
the cable provided that you have a proper crimping tool and are happy
with how it's enclosed. Another way, if you are concerned about the
accessibility of the joints is one of the new Hager Ashley maintenance
free junction boxes:

http://www.tlc-direct.co.uk/Products/ASJ803.html

Those have spring contacts and good cable clamps and IME (of the smaller
lighting ones) *very* well made.

In my view, these are unsuitable for inaccessible connections and do
not comply with the regs for this purpose.

Ashley's use of "maintenance free" would appear to mean they provide
no means to perform any maintenance, not that none would be required.
Indeed, with the absence of large surface area gas-tight contacts
which are present in all the proscribed [maintenance free] methods for
inaccessible connections, I would expect a shorter lifetime from this
product than from standard screw terminals, and as such, thoroughly
unsuitable for an inaccessible connection.

Not used one myself though.


Indeed. These things (Ashley in particular) keep getting mentioned on the
IET forums in exactly this context and opinion goes both ways.

Obviously Hager are strongly hinting that they are suitable. all I can do is
quote:

"The screwless push to fit terminals do not relax, and so do not require
inspection." from:

http://www.hager.co.uk/building-auto...tures/6387.htm

It would be interesting to challenge them on the specifics.


You're an engineer and obviously your opinion is worth much and I can see
your argument.


I've used them in a semi-accessible location (under floorboards), where
there's some flex in use (SELV downlighters, I use high temperature
silicone flex) and they are very good for this (because the contacts are
suitable for solid or flexible and the cable clamps being present).

I should note that the springs are pretty strong in these. Whether the
springiness can be proven not to decline in time or whether the contact
pressure is sufficient to prevent oxidation of the cable I couldn't
comment.

Cheers

Tim

--
Tim Watts

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