Oops!

Conductor wrong side of clamp eh?


Z.

Twenty two years!

Quite an impressive near miss. I assume that is  the reason for the length of new brown tail. Seeing as the damaged  the clamp looks shut, was the original  just held in by faith then ?

One RCD supplying three 32A breakers and a couple of 16As has potential to be more than just  a light load.

22 years must make it one of the earlier split load boards.

The missing MCB is the B40 that is welded to the RCD, the shower it supplied has been removed so I have terminated the circuit into the MET and not replaced the MCB. The wholesalers only stock MK internal tail kits and they are not long enough for this  consumer unit, so the replacement tail is tri-rated cable.


What you have not picked up on is the standard of the original installation which is neat with each conductor numbered, I know the guy who installed this, he is now retired however I worked with him thirty years ago when I was on a site as a carpenter and he was the electrician, he could be best described as fastidious or an anorak, he always struggled to make a living because he was gold plating his jobs when the customers were not paying a premium price, he missed this though.


It is amazing it took twenty two years for the problem to become an issue, the end of the internal tail burnt off and you can see it in the terminal.


Andy Betteridge

Nice warm home for the spider to live in though?

Not a lot!


The spider is copper, the original tails were the sleeved plaited fine stranded cable with crimps on the ends applied that appear to have been pressed into place with a dirty great steam hammer, which was lightly contacting the back of the cage clamp, it's surprising it lasted twenty two days never mind twenty two years.


Andy B.

But why the presumption it was the original installer?


With those boards, as many others with that busbar arrangement, the usual practice is to completely remove the bar, re-arrange the MCBs, then refit the bar.


I bet it was they that "upgraded the shower".

The shower upgraded was removing the electric shower and installing a mixer shower, I did ponder if it could have been like that from assembly in the factory, but if it had the manufacturer would pass the buck to the installer.


Finding things like this leads to obsessive tugging of cables with the long nosed pliers.


Andy B.

I wonder if the bad connection "arc welded" itself so that it performed so well for so long. I have come across a 40 Amp shower circuit where the busbar just contacted the M.C.B. by spring force as it had not been clamped under the terminal clamp. Remarkably it showed no sign of overheating or damage.


Z.