Nuisance tripping.

[Dustydazzler]

So it works out cheaper to buy RCBOs as a CU package and just put the CUs to one side.

Yes if it’s on offer

 

[Charlie_]

And serious hassle when it starts tripping ...

Fitted many hundreds, and never had any serious hassle..
Had the odd issue where a neutral has been crossed over to wrong side and that’s about it.
What are your thoughts on very high earth leakage currents upstream of the consumer units?

 

[Octopus]

Fitted many hundreds, and never had any serious hassle..

I've done so much fault finding on existing installations over the years on single , split and dual RCD boards I stopped fitting them at AMD3

RCBO boards are far easier to test, now and in the future ............

Its not about hassle for me, its about saving clients serious trouble, and costs going forward.

As for upstream earth leakage - not come across this .................

 

[Octopus]

So it works out cheaper to buy RCBOs as a CU package and just put the CUs to one side.

And you can take out the RCBO's you don't need, then when you have enough stock simply buy a bare chassis with DP switch and use the spares ......... kerching.

 

[Charlie_]

Well just for the record, I’m all for RCBOs too..

Next time you get chance do a few tests upstream and observe the earth leakage.
Think you will be surprised by how high this can be, especially on large installations.

 

[Octopus]

Well just for the record, I’m all for RCBOs too..

Next time you get chance do a few tests upstream and observe the earth leakage.
Think you will be surprised by how high this can be, especially on large installations.

“Informative”

 

[DPG]

"Friendly"

 

[marconi]

Firetrekker - what part of the UK is the job? Some EF folk might be close by and willing to help if you are a little stumped.

It is also worth sitting down quietly - with a pint, pen and some paper - and thinking through what it might be and how you could methodically discover or discount circuits/appliances. It will not be the last time you have to so good practice. Some good prompts already on test equipment you might borrow or buy and 'ways ahead'. So do some thinking before you next visit and sketch out a plan of attack. You might want to buy some RCBOs say 6A, 20A and 32A to leave some final circuits protected by them rather than the RCDs - in case the fault happens to be intermittent and not easily stimulated - then at your next visit you will have some new information from how they and the RCDs react.

 

[richy3333]

What’s this cheapo RCBO board?

 

[Octopus]

So do some thinking before you next visit and sketch out a plan of attack. You might want to buy some RCBOs say 6A, 20A and 32A to leave some final circuits protected by them rather than the RCDs - in case the fault happens to be intermittent and not easily stimulated - then at your next visit you will have some new information from how they and the RCDs react.

Doesn't that rather depend on the CU make - it may not be able to be configured in such a manner

 

[Midwest]

Good point, but lets not stem the thought processes.

 

[Firetrekker]

Eliminating appliances for accumulation is no good really..
You remove 1 non faulty appliance and hey presto all is ok. Replacement gets bought, plugged in and RCD trips again.

No , I’m going to ramp test the rcd against each circuit building up to full load, then see what the earth leakage is. I’m then going to see if I can re balance the splits and if not retro fit RcboS, I suggested these to start with but as usual they didn’t want the cost.

 

[Octopus]

No , I’m going to ramp test the rcd against each circuit building up to full load, then see what the earth leakage is. I’m then going to see if I can re balance the splits and if not retro fit RcboS, I suggested these to start with but as usual they didn’t want the cost.

rally?

 

[Firetrekker]

Hi all, to answer a few questions, there are two original circuits which is where I’m getting the low IR, I have ramp tested the reds but the house wasn’t full of stuff as there weren’t living there, so I will now again one circuit st a time, increasing until I get the full split powered up and then see what the earth leakage is. Then either rebalance board or go with rcbos. Thanks for all you help .

 

[telectrix]

suggestion. with all loads connected, ramp test the RCD that's tripping, note the reading. then ramp test again with loads isolated. the difference in readings will be roughly equal to leakage. then try to track it down by adding loads 1 at a time.

 

[ferg]

What’s this cheapo RCBO board?

I think it's Lewden and they are cheap in Englandshire.

I can't get them from Wholesalers and have seen them only once, jammed in to a crappy proteus board.

I stick to Hager but as they are a good bit dearer customers always go for the Dual board.

 

[richy3333]

Thanks ferg.
Where’s this Englandshire, sounds like a land of milk and honey