Help with testing a CU install and signing it off

[Smart Sparks]

Hi all,
I am in need of some advice ahead of my ELECSA assessment onTuesday 28/08.
I decided to replace the Consumer Unit in my house and testsome Minor Works. All has been going well, replaced the CU no trouble all readyfor testing.
The trouble started when I completed the InsulationResistance test on the house ring. I was getting strange readings so checkedevery visible connection at each SO, everything was in order. I then rememberedthat we have a socket in a cupboard adjacent to our front door. It is wired inSWA and the cable runs down the side of the house and enters the housesomewhere near the CU. But when I changed the CU there was no sign of the SWAand the space between the wall and the plaster is around 10mm so I neverconsidered it may be connected direct into any of the circuits. I suspected it would be connected to one ofthe RM socket outlets for the kitchen.
However on the end of it is a Double RCD socket and when I disconnectedit the Insulation Resistance readings were fine. So somewhere in the wall it isconnected to the ring.
The ring is a 32amp conventional ring main in 2.5mm cablethe SWA appears to be 1.5mm.
Not sure what to do, do I leave it and explain to ELECSA Ifound it this weekend and will need to find the connection and remove it?.
Or will he fail me straight away if I tell him that?
In a real dilemma as if I deal with it this weekend I willnot get t repaired in time for the ELECSA visit.

Any help or advice would be really appreciated.

 

[telectrix]

you will also probably have 2 RCDs in series. the 1 in the CU and the RCD socket. my advice is to take the RCD socket off. block the SWA cable ends with either choc block or wagos. firt a blank plate over and tell the assessor what you found, and that you will remedy it when time allows.

 

[Smart Sparks]

Thanks for the advice.

I will try to get a blanking plate but with it being bank holiday not sure if I will be able to. I will disconnect socket and put in choc blocks though.

The CU has 2 RCDs, when completing IR test on entire board is it ok to turn RCD;s to off position and test via bottom of MCB's which are effectively connected together?, come to think of it would I need to do it twice for each set of MCB's off each RCD as they are seperated.

 

[Strima]

If needed and desperate the big orange shed (B&Q) stocks stuff like that for a price... Only £12.89 for a blanking plate... :lol:

Fine to use the busbar for IR testing, just make sure any RCBO's are disconnected as well, they have a thing for DC currents... Any low readings then split the circuits down, have had some MCB's in the past be a bit picky. Make sure all loads are disconnected and start at 250V to be safe.

 

[Deleted member 26818]

You disconnected the socket-outlet, and the readings were fine?
This suggests that the socket-outlet is dodgey.
Why not stick a non RCD socket-outlet on?

Make certain that both the RCDs and the main switch is off

 

[Guitarist]

The RCD socket may not even be one now that he's IR tested it....

 

[telectrix]

with the RCDs and MCBs off, test L-N from top side of MCBs in turn to N bar. likewise for L-E (to E bar). (you could do a global from L busbar with MCBs on). then N-E from E bar to N bar for global reading or pull out all the N's and test each to E bar

 

[Guitarist]

In reality, the assessor will not check everything on the EIC. He will check all your paperwork, grill you on electrical regs + building regs, then get you to demonstrate some aspects of your job, such as safe isolation and taking EFLI readings. Disconnect anything which you don't consider compliant or safe, then after your assessment sort it out properly if you are worried.

 

[Smart Sparks]

Thanks all for your advice. Im probably getting a bit worried because of the ELECSa thing would hate to waste the hundreds of pounds I have paid out only to fluff it on something like this. Have been careful not to IR test RCD's in the DB, as I did a full Ring Final check and didnt see the SWA connected anywhere I assumed it must be on the kitchen ring. Cant belive someone has cut into the ring somewhere unaccessible, as the house is only 10 years old and there are not signs to show this would be the case.

Thanks again for all your advice.

 

[Strima]

Cant belive someone has cut into the ring somewhere unaccessible,

Welcome to the world of domestic bodge ups... There's worse to come, believe me...

 

[Guitarist]

Welcome to the world of domestic bodge ups... There's worse to come, believe me...

ohhh yes....much, much worse....

Just remember the motto that non-electricians live by.... "It works, dunnit?"

 

[Smart Sparks]

Thanks everyone for the advice. Had my assessment Tuesday and all went fine so now ready to go find some more bodge jobs !!!! I found the assessment really useful and got some good advice around my testing which should stand me in good stead. Thanks again.

 

[Guitarist]

Thanks everyone for the advice. Had my assessment Tuesday and all went fine so now ready to go find some more bodge jobs !!!! I found the assessment really useful and got some good advice around my testing which should stand me in good stead. Thanks again.

Gratz mate. Don't forget to use the Elecsa tech helpline as often as you need to.

 

[Smart Sparks]

Will do cheers mate.