In my experience screwed terminals or connection blocks cause most of the
faults in wiring which has been in for some years. I think the copper
actually relaxes and hence the screw seems loose, assuming of course there
is no nasty corrosive environment around them. Only a few months ago I had
to tighten screws in a 13A socket that was getting warm.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Jeff Layman" wrote in message
...
On 14/10/19 12:58, Tricky Dicky wrote:
I was connecting a cable to a junction box that I had fitted some years
back and noticed the terminal screws though secure were not particularly
tight which is unusual for me as my torque settings are normally one
grunt + 1.

The junction box was fitted to a joist and it made me wonder if the act
of walking over the floor at that point was causing enough vibration to
ease the screws off? I it is the cause then it certainly makes the case
for Wagos.

Richard

It's an interesting point. I wonder how Wagos would fare after 20 years?
Would they suffer from vibration-induced metal fatigue, and their spring
grip be lost? And as they aren't screwed down, would the terminal screws
have become loose if subjected to the same treatment? In other words, if
the screws had been in "flying" connector blocks, and so subject to
little - if any - vibration, would those have become loose?

Out of interest, why do the wiring regs require junction boxes to be
screwed down? They don't tend to move around with twin and earth cables in
them, anyway. Why would you expect them to move under floorboards or in
ceiling spaces?

--

Jeff