Breaker tripping

highspark · Nov 20, 2011

Lads odd fault.

Breaker trips 20 mins-1 hour after being switched back on. 32 amp ring, old wylex board with push fit circuit breaker. Wiring is a mess. Ring is for sockets. It has exterior lights, alarm, boiler , attic lights, pond pump and fountain - all from jb's in attic - thoughts definate overload. Problem is I've unplugged everything and it's still tripping. There's a load bang in the attic everytime it trips. Any thoughts?

highspark · Nov 20, 2011

Wiring is a rats nest. If it's happening after a certain period of time I'm thinking definate overload or maybe loose connection heating up!

Hawk81 · Nov 20, 2011

Have you clamped the circuit? What tests have you done? IR?

UKMeterman · Nov 20, 2011

Loud bang == Lots of energy in fault.. Check for rodent damage, and get the megger out...

highspark · Nov 20, 2011

I've done ir tests on it and both came back fine. There is far too much on the circuit as it so it needs to be rewired but the loud bang leaves me to believe the fault is up in the attic! I'm going to clamp it tomorrow never had my clamp today!

Engineer54 · Nov 20, 2011

Hmmmm!! large bang in the attic!!! i wonder if the problem has anything to do with something shorting in the attic area??

Look around for black sooty deposits, and you will have found your problem me thinks!!!

Hawk81 · Nov 20, 2011

Engineer54 said:
Hmmmm!! large bang in the attic!!! i wonder if the problem has anything to do with something shorting in the attic area??

!!!

Couldn't be? Could it??

highspark · Nov 20, 2011

If its shorting it must be after the cables heated up and expands because it happens every half an hour or so and the ir tests where fine.

Engineer54 · Nov 20, 2011

Well, ...if you go up in the attic, ad have a look around, open any accessories up there, your gonna see where the short is taking place. Could and probably is, on the upstairs lighting circuit that you say is fed from the RFC... The connections as such being poked thru ceiling into the attic ...

MarkieSparkie · Nov 21, 2011

Engineer54 said:
Hmmmm!! large bang in the attic!!! i wonder if the problem has anything to do with something shorting in the attic area??

Look around for black sooty deposits, and you will have found your problem me thinks!!!

Remember to safely to double pole isolate the supply at Main Switch or RCD, your safety when looking for the damage may depend on it.
Look for signs of thermal damage, rodent damage, water leaking on JB or accessory (from header tank or roof), e.t.c.

Short Circuit · Nov 21, 2011

could also be squashed cable, where people have walked on the cable pressing it into the joists, or someome has put flooring in the loft with the cable between that and the joist! Would have expected that to show up on an IR test though! You say IR test were OK, what were the readings? Cant see how overload would occurr if you have unplugged everything?

nickblake · Nov 21, 2011

large bang in the attic , insulations tests ok well its not water then other wise that woulsd show up could be a screw or nail though a cable just not quite touching had that fault which didnt show up on IR tests ,switch it on go in the loft in the dark and look out for the flash just make sure your not sitting on it , , na i would go in the loft and phisically check the cbales for damage let us know what it is mate

Rockingit · Nov 21, 2011

Got a cam corder? Safer than you being up there, and the footage of a nice big flash will probably get the customer to do anything you suggest to them!

highspark · Nov 21, 2011

Lads thIs one is doing my nut.

The property is a bungalow. The circuit is a ring. It's been added onto over time - badly. It has the boiler wired in directly from a jb in attic. It has a socket in the attic feeding an extension lead feeding the pond pump and shed sockets which can be unplugged - unqualified work! It also has attic lights and outside lights connected from jb's of ring to fused spurs. It also has aan alarm which again plugs into an extension lead from socket in attic. It also has undercupboard lights and a phone plugged in - and that's just the first half of the ring. The ring then goes down and under the floorboards feeding tv's lamps and computers. It's heavily overloaded. But i've unplugged everything & removed fuses from fused spurs. And still trips at intermittent times. It's been lasting 3 hours today and 30 mins the day before. I've IR'd all cables in the attic broke at jb's and tested from end to end and all have tested fine.

After putting it all back (not plugs bulbs and fuses) I did IR's at DB and got reading across the board of 0.01mohms. Anyway spent a full day there and left. Customer phoned before. Tripped after 3.5 hours everything unplugged!!

Absolute joke any thoughts - or rewire the circuit? Probably save money and time.

Des 56 · Nov 21, 2011

There's a load bang in the attic everytime it trips.

If you have done your best with the test meters and considering the state of the install,it may be that its time has expired,upsetting I know