mcb and rcd tripping intermittently

[dancol]

mysocket ring mcb kept tripping, which caused the rcd to trip..a very old board. ive since had the board replaced as the rcd wouldnt reset and was obsolete.
unfortunatlry my sockets mcb continues to trip internittently...driving me mad now!!

2 electricians couldnt find a fault that causes the problem...anyone help please??
thanks

 

[securespark]

OK, your sparks (2 x) could not find a fault and they were there...

We are here....what chance have we got?

 

[plugwash]

which sockets does this ring cover?

what is the maximum load you typically place on it?

unfortunately intermittant faults are by nature very difficult to diagnose, it could even be a fault in an appliance (plug fuses will not dependablly discriminate with B32 mcbs)

 

[jj4091]

Do YOU HAVE ANY APPLIANCES FITTED WITH A DOUBLE POLE SWITCH? DOES ANY PARTICULAR APPLIANCE CAUSE THE MCB TO TRIP?



++++++++++++
Moderator's note:

Please switch off your CAPS LOCK

Mod Rupert
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[Steve]

(plug fuses will not dependablly discriminate with B32 mcbs)

indeed. especially when you spill water all over the kettle's cordless base

 

[dancol]

ive left the appliances all unplugged and the mcb still trips, even overnight when the house is closed for the evening...evrything turned off and unplugged. even fridge and freezer.

happenning mainly on downstairs sockets, but occassionally the rcd trips too.

 

[sm1thson]

have you put any nails/ screws in the walls recently? and signs of mice or rats? -get some traps down just in case!

 

[Diyisfun]

Have you checked the SOCKETS I had a bad connection in a socket, it was tripping randomly, It was a lose connection arcing.

SWITCH POWER OFF FIRST

 

[JohnD]

Mice gnawing the cables.

 

[dancol]

ive had all apliances unplugged and it still trips....in middle of doing a bypass on the ring to see if it works..looking hopefull, which means that there was a fault between 2 of the sockets on the ring...fingers crossed.
if it doesnt trip while bypass is in place, I'll do a surface mounted rewire for those 2 sockets.

thanks for all your help.
will let u know if it works.

 

[dancol]

now it gets interesting!!

my attempt at bypass stopped the sockets tripping, but left me with a particular socket not working on the downstairs ring, same room as bypass but other wall (.call this socket A)

so i tried putting back as before , removing bypass...but disconecting earth leads between the 2 sockets id bypassed.

this has resulted in no mcb or rcd tripping, all working fine....except socket A, which when i plug in a tester shows...N and L reversed.ive opened it, and their not reversed.

very puzzling.

could this socket be a branch off the ringmain.

 

[DESL]

I have some concerns about what you're describing

1. Did you get an Electrical Installation Cert when the comsumer unit was changed in other words was a full schedule of tests carried out.

2. Disconnecting earth wires will leave the installation in a potentially dangerous situation as you may have disabled the MCB & RCD obviously as they are not tripping now. You may have not isolated the fault as well.

3. The 2 sparks you used should not have left the installation with MCB and RCD tripping however difficult it is to find the fault!!
To be frank the fault should have been diagnosed before any CU change.

 

[dancol]

i appreciate what your saying, but wot am i to do?
if sparkies cant find it.

 

[DESL]

sparkies should find it!! Get them back as they are duty bound to sort it

i.e. you got them in because of MCB/RCD tripping and when they finished MCB/RCD still tripping they haven't completed the job they were asked to do.
And there should be no charge either!!!
If you used a spark in a scheme then you do have recourse to the scheme provider

In the meantime I suggest you switch off MCB for faulty circuit

 

[dancol]

when i tried getting first one back, he was @too busy with other jobs@ hes the one that bypassed half my cu board and disconnected one earth lead to @get me going again@.

second one going to ring me later today.

thanks