RCD nuisance tripping

[plugsandsparks]

The current regulations have been interpreted as requiring a minimum of 2 RCDs which typically would cover 10 circuits. Increasingly this is not good enough to avoid nuisance trips and enable speedy diagnosis of a fault. RCBOs cost between 5 and 10 times the cost of a MCB

Assuming appliances is at fault, good candidates are: Steam iron, toaster, oven, dishwasher.
Any wiring or fittings that go outside are potentials.

You need an electrician with the right equipment to measure leakage whilst appliances and other loads are applied and take it from there. Its unlikely that the fault would not present itself in some form even if a trip does not occur at that time.

 

[rad1o]

We can trigger the trip if we "rev" the electric appliance, i.e. start repeatedly. We can also trip the socket ring on the RCD side with a light switch being flicked on and off at speed with the light ring sitting on the non RCD side. Sometimes the RCD does NOT trip with almost everything on. But the RCD could also trip with hardly anything on. It was tested and found to be ok.
Would it be legal to have a socket ring on a non-RCD side on its own 32A RCBO. I know it does not cure the problem.
What would I gain to know the earth leakage?

 

[telectrix]

you would need an earth leakage clamp meter. cost from around £90 to £300+ . cost less to get a spark to find the fault.

 

[plugsandsparks]

We can trigger the trip if we "rev" the electric appliance, i.e. start repeatedly. We can also trip the socket ring on the RCD side with a light switch being flicked on and off at speed with the light ring sitting on the non RCD side. Sometimes the RCD does NOT trip with almost everything on. But the RCD could also trip with hardly anything on. It was tested and found to be ok.
Would it be legal to have a socket ring on a non-RCD side on its own 32A RCBO. I know it does not cure the problem. There is no other way
What would I gain to know the earth leakage?

For a start you would not be wasting time trying to make it trip by rapid switching. You can measure the leakage that the RCD is seeing at anytime, you can introduce loads one by one and in combination, you can also see if the leakage is fluctuating due to external factors. You can also check live and neutrals are balanced on each cct just in case its not wired correctly. There will be a pattern you are just not seeing it.
Good Luck finding it.. generally they never improve so it may become more obvious over time.

 

[Octopus]

For a start you would not be wasting time trying to make it trip by rapid switching. You can measure the leakage that the RCD is seeing at anytime, you can introduce loads one by one and in combination, you can also see if the leakage is fluctuating due to external factors. You can also check live and neutrals are balanced on each cct just in case its not wired correctly.
Good Luck finding it.. generally they never improve so it may become more obvious over time.

Only if the OP has the necessary tools and knowledge!

 

[Marvo]

Replacing the RCD with RCBO's is treating the symptoms and not the cause of the problem. This is a poor strategy that can be unreliable and can work out expensive. Find the fault, fix the fault, end of problem. If you don't have the equipment or the competence then get someone in to do it.

 

[Knobhead]

If there’s a shared neutral between the sockets and lighting, RCBO’s are just going to make matters worse. Or am I being to logical.

The OP has to accept that the fault has to be found and stop faffing about with impractical ideas.