Rcd problems

[sidekick]

Following the addition of a socket to a ring circuit I have just carried out the RCD trip test with a Fluke tester.
The RCD would not trip on x 1 or x 5. Then tried the test button on the RCD and it would still not trip even with all the circuits turned off.
On closer inspection found that the line conductor to the RCD was connected at the base along with the bus bar (bypassing RCD) also found a link had been added between the two neutral bars.
After speaking to the customer it transpires that on fitting of a new kitchen the electrician also convinced them a new consumer unit was required (no reason not to believe that) However, after fitting the split load unit the RCD constantly tripped on all socket circuits ( x 4 ). Customer was advised too much leakage and the RCD was bridged to allow power to all circuits.

What is the best way to go about putting this right to give RCD protection.

 

[topquark]

First, have the idiot that provided bypassing the rcd as a "solution":61:

It'll be down to finding the cause of the leakage and either addressing it or splitting the offending appliance(s) onto separate circuits.

 

[ringer]

Too much leakage? It sounds very much a bodge job by someone who did not know enough about what they were doing. I would suspect circuit is wired incorrectly (neutral on wrong bar?). First off I would install the rcd correctly, turn off/disconnect all other circuits so the rcd is the only thing that is energised, then test to ensure the rcd is not faulty. Then I would get my wander lead out and check all connections on that circuit. It beggars belief that someone would leave the installation in that state!

 

[IQ Electrical]

Following the addition of a socket to a ring circuit I have just carried out the RCD trip test with a Fluke tester.
The RCD would not trip on x 1 or x 5. Then tried the test button on the RCD and it would still not trip even with all the circuits turned off.
On closer inspection found that the line conductor to the RCD was connected at the base along with the bus bar (bypassing RCD) also found a link had been added between the two neutral bars.
After speaking to the customer it transpires that on fitting of a new kitchen the electrician also convinced them a new consumer unit was required (no reason not to believe that) However, after fitting the split load unit the RCD constantly tripped on all socket circuits ( x 4 ). Customer was advised too much leakage and the RCD was bridged to allow power to all circuits.

What is the best way to go about putting this right to give RCD protection.

Amazing, anyone looking at that consumer unit in future years (possibly 10 years if a normal-interval next inspection sticker was applied) would just assume that RCD protection was adequate!

I'll bet on a N-E fault somewhere, get the insulation resistance tester out!

 

[Hawk81]

I would guess there is a neutral to earth fault somewhere and the cowboy that fitted this CU could not be bothered to find it.

 

[oxocube]

Remove the link between the neutral bars and the bypass and then retest, if all ok. Reconnect circuits one by one until you find the one that trips the rcd. The tripping could be due to a fault or excess earth leakage, a 30mA rcd will trip at around 20mA thats the equivalent of 3 pc's and monitors, so have a look around for leaky things.

Also be suspicious of any external equipment and the kitchen/utility room.

Happy hunting.

 

[Knobhead]

Christ on a bike! You’re serious! He bridged the RCD?

Find the company and have them held accountable (linched)!

I’ve done some mad things in my time but not with out knowing what I was doing!

 

[Rockingit]

Find the company and have them held accountable (linched)! !

I'm with Tony on that - that 'Electrician' should feel the full weight of Trading Standards / H&SE. There are times when you may be forced to do something 'less than ideal' but safe and just about legit, and then there are times when we find things that can kill people, put there knowingly by people claiming to be expert enough to charge for doing it. Read the thread about the dead plumber - nuff said.

 

[Octopus]

The electrican that did that is a twxt.

I hope that the customer understands that what you recommend, i.e. find the fault and wire the CU properly is necessary and is willing to pay for it.

Have fun!

 

[spark 68]

Unbelievable!,

I would not be able to sleep at night, having said that I would have never ever done this in the first place.

Was there any paperwork ?, ...Iam guessing not

 

[Octopus]

I think the clue is in the OP "having a kitchen fitted"

 

[Knobhead]

Too Bloody True!

 

[sidekick]

Thanks for all the comments guys. No paperwork available for any previous work.
I removed the link and checked all circuits had neutrals on correct bar, wired the RCD correctly and the RCD tripped with all protected circuits on. I removed neutrals one at a time and still always tripped (suggesting more than one circuit with fault) I then removed all neutrals and connected one at a time which gave me the correct function on 2 of 6 circuits.
4 socket circuits continued to trip the RCD and my next job is to find the fault on those circuits.

 

[topquark]

Test the RCD in isolation (with no other circuits attached) and ensure the test button is working correctly (the RCD may be faulty).

 

[IQ Electrical]

Thanks for all the comments guys. No paperwork available for any previous work.
I removed the link and checked all circuits had neutrals on correct bar, wired the RCD correctly and the RCD tripped with all protected circuits on. I removed neutrals one at a time and still always tripped (suggesting more than one circuit with fault) I then removed all neutrals and connected one at a time which gave me the correct function on 2 of 6 circuits.
4 socket circuits continued to trip the RCD and my next job is to find the fault on those circuits.

Maybe the rings are interconnected, go back to basics, ring continuity checks and IR testing, assuming no loads, these 2 tests will give you all you need to know.