"Andy Hall" wrote in message
...
On Wed, 10 Sep 2003 22:45:38 GMT, "BigWallop"
wrote:




Yes there are other options, but which ones are the safest ? After many
years of trials on site, I've always found the correct way to be the
safest
way every time. :-)) Aesthetics don't always come into play when safety
is
involved.


Absolutely, but I don't think that in this case there is one "right
way" to the exclusion of all others or that one is inherently safer
than the rest. It would also be fairly difficult to say which out
of several methods is more mechanically sound.

The main reason for the question was to get a range of views because
the specifics are not covered in the Wiring Regulations except in the
broad sense of good workmanship (a matter of opinion), and a few
specifics such as accessibility to terminals, earthing arrangements
etc.

If there were a single "correct solution" it would be publicised by
the manufacturers and industry authors.

.andy



Just an extract from the bible of electrical engineers:

Toothed and serrated lock washers of phosphor bronze must be used where any
cable termination is used to carry fault signalling. The basic principle of
these washers is to use the spring reaction of their hardened teeth to bite
into both the work piece and the locking nut and gland body, so effectively
ensuring the tightening torque is maintained even under pull strain or
vibration conditions and to improved electrical contact (e.g earthing
terminals).

And.

Where PVC/SWA/PVC cables are used as main or sub-main cables, all
termination's shall comprise of compression glands of correct size for each
cable and fitted with earth bonding washers, star washers and separate
copper bonding directly to the earth terminal of the equipment. The whole
gland assembly shall be fitted with a PVC shroud after the cable is fixed
and earth bonded. If calculations show that the armouring of the cable is
insufficient to be used as the sole circuit protective conductor, then a
separate additional C.P.C. shall be installed. This may be in the form of an
additional core of the cable itself, or alternatively a separate conductor
secured to, and in parallel with, the cable and connected directly to the
earth terminal of the equipment.

So there is a correct way to do it Andy.


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