RCD tripping overnight with nothing connected

[leew85]

Good evening. Had a new consumer unit fitted a week ago, Paid over £500+vat for a proteus 5+5 board to replace an old non-rcd board. Ever since it was fitted the right hand RCD has tripped in the middle of the night, between around 11pm and 7am, every night. This powers a socket circuit, an oven, hob and an alarm. The oven and hob were isolated at the control switches and the ring had nothing plugged in. In order to attempt to figure out what was causing the tripping I switched off the oven, hob and ring MCBs, leaving just the alarm on, it still tripped. I then disconnected the 3 neutrals for those circuits from the neutral bar and taped them up, it still tripped. I then disconnected the alarm, leaving nothing connected to the load side of the RCD, it still tripped. So I called the guy to report my findings that I suspect the RCD is a dud, as cannot see why else it would trip with no load connected. He turned up, used an RCD tester to make sure that the RCD tripped within range, which it did, said the RCD was fine and left. Guy who fitted it claimed there was a borrowed neutral somewhere, but really struggling to understand how the hell that could cause an RCD with no connection to the load side to trip. Can anyone here explain to me how the hell an RCD with no load connection can trip overnight like this?
Thanks, Lee.

 

[MJPD29]

sure thing, outside and inside.
On an unrelated note, are there any regs concerning how far back the insulation is stripped on the incoming tails? I don't like the fact there is a few mm of live tail showing and would have thought the tail insulation should touch the main switch body? I was told by a mate years ago when wiring sockets etc to never leave bare cable showing outside the terminals. This is how it was when fitted with the exception of the disconnected neutrals in the top right and also a groove I cut in the wall to the left in order to get the cover back on without stressing the breakers. I took care to cover the electrics with some plastic sheeting and masking take to avoid any debris getting inside.

No cover on the busbar? Doubt it arrived like that. A lot of copper showing. Generally poor workmanship, my guess is no testing and wouldn't know how to find the fault anyway. What is the black tape in top corner also?

 

[Timbo]

Who in their right mind uses Proteus anyway? ??

 

[leew85]

It looks from your photo that the neutral link to the terminals is in the bottom of the main switch, and there is no neutral link in the bottom of the rcd.
<snip image>

yes, there is a neutral link from bottom of RCD to neutral, you just can't see it in that picture due to the camera angle

 

[leew85]

No cover on the busbar? Doubt it arrived like that. A lot of copper showing. Generally poor workmanship, my guess is no testing and wouldn't know how to find the fault anyway. What is the black tape in top corner also?

Black tape is to cover the exposed ends of the disconnected neutrals to stop them inadvertantly touching something they should not.

 

[brianmoooore]

Ah well, it was a good theory while it lasted.

 

[littlespark]

Thanks for clarifying the neutral link query.... im sure someone later will ask you again, as they wont read every post... #33... i'll remember.


A question though. Does it only trip during the night? That sounds like its a timed piece of equipment such as storage heating or off peak water heater. Maybe the neutrals are mixed up between the on and off peak immersions?

Scratch that.
Just looked at the original photos, and theres no off peak heating marked up.

 

[leew85]

Thanks for clarifying the neutral link query.... im sure someone later will ask you again, as they wont read every post... #33... i'll remember.


A question though. Does it only trip during the night? That sounds like its a timed piece of equipment such as storage heating or off peak water heater. Maybe the neutrals are mixed up between the on and off peak immersions?

Scratch that.
Just looked at the original photos, and theres no off peak heating marked up.

Yes, only at night, no night storage heaters, no timed or light sensitive or PIR lights. Only things on overnight are the alarm, gas boiler and Google nest thermostat for said boiler.

 

[westward10]

I have deleted your video from your latest post as it shows the name of the contractor. If you can edit this out feel free to post it again.

 

[brianmoooore]

I have deleted your video from your latest post as it shows the name of the contractor. If you can edit this out feel free to post it again.

Too late!

If the RCD turns itself off with no neutrals connected, and all MCBs fed from it also off, it can only be a dud RCD.

 

[SagaCU29]

Too late!

If the RCD turns itself off with no neutrals connected, and all MCBs fed from it also off, it can only be a dud RCD.

Or a loose connection.

 

[leew85]

Too late!

If the RCD turns itself off with no neutrals connected, and all MCBs fed from it also off, it can only be a dud RCD.

So they are bulling me basically? Need to try and decide how best to put that into nice words and get them to fix it. Either that or get my money back and get someone else to fix it. I was initially offered either a fixed price for the install, or I could have had it done for an hourly rate, which worked out cheaper based on their estimation of the number of hours needed but could end up costing more if more time was needed. I stupidly chose the fixed price thinking they would fix any problems like this but seems not. I got burned by another guy a few years back accepting an hourly rate and the job took longer than it should have done and I was not around the whole time so probs ended up paying them for smoke breaks etc. Wondering if it would be reasonable to ask for a refund on the difference between the 6 hours of labour Vs the price I paid? Also ask for the receipt for the board so I can take it back to CEF if needed?

 

[westward10]

You have done all that you can to resolve this issue and they should return at no cost to you to remedy it.

 

[stevethesparks]

If they are a professional outfit (doubtful looking at the pics) they would have no hesitation returning to sort out any problems, and hopefully tidy that mess up, including dressing the cabling properly, uprating those RCD's and installing the bus-bar cover. You shouldn't have to be inside the CU disconnecting anything to try and solve someone else's mess. Demand that paperwork too, or get straight onto PayPal.

 

[westward10]

Yes I forgot about the busbar shield, the unit is incomplete without it. All you can do is ask for them to resolve these issues or say you are going to lodge a complaint to the NICEIC.

 

[leew85]

I have deleted your video from your latest post as it shows the name of the contractor. If you can edit this out feel free to post it again.

Whoops, sorry.
Take 2: