Volex 10-Way - 30mA 80A RCD keeps tripping

[Zehroni]

Dear All,
We have Volex 10-Way Fully Insulated Dual RCD Consumer Unit in our house all the circuit are connected to 30mA, 63A RCD apart from one socket which installed by the consumer unit and is connected to 32A breaker on the side of the 30mA 80A RCD. This RCD kept tripping no mater what I connect to the only socket connected to it. I replaced it with a new one and worked perfectly for 10 days then tripped again last night. I have switched off the only socket connected to it and still can put on, every time I try to put it on comes down again immediately, any idea please

 

[Spark123]

Seems like a bit of an odd setup, all circuits on one RCD bar one circuit??
Is almost as bad as only having a CU with an RCD main switch. I'd get the installer back and give them a hard time!
As the socket has worked in the past then it being connected to the wrong neutral in the CU isn't likely, has the cable been damaged? Where it enters the socket there any sign's of damage. Had one once where the installer had used the knockout behind the back box screw on a surface mounted socket, when the socket was screwed in place it caused a N-E fault as the screw had pierced the cable.

 

[Chri5]

We have Volex 10-Way Fully Insulated Dual RCD Consumer Unit in our house all the circuit are connected to 30mA, 63A RCD

Would you please confirm why all the circuits are on 1 x RCD, if the board is dual it's should be 50:50 with the circuits, as in half on one side, half on the other.

one socket which installed by the consumer unit and is connected to 32A breaker on the side of the 30mA 80A RCD. This RCD kept tripping no mater what I connect to the only socket connected to it. I replaced it with a new one

Did you replace the RCD or do you mean the socket ?

worked perfectly for 10 days then tripped again last night. I have switched off the only socket connected to it and still can put on, every time I try to put it on comes down again immediately, any idea please

What are you pluging in to it ? Might that be the problem ?

Would you give me some sort of idea on your skill set are you a DIYer, someone with electrical knowledge, someone with measuring and test equipment or ?

A picture of your fuseboard and general layout might help.

 

[Zehroni]

Hi Park,
non of the possibilities you mentioned exist, the wire is very short and not damage. I can see that the whole wire and both entries to the socket and the CU. Do you think it is faulty RCD again.

 

[Spark123]

It has got to be something faulty as it has worked.
As Chri5 has said, try plugging in something else such as a table lamp which is double insulated.
What did you have plugged in that worked for 10 days?
Can you upload a couple of pics, one of the CU (with it turned off) with the cover off?
One of the back of the socket?

 

[Zehroni]

I will upload some pics, but my problem now is that the breaker is off and nothing going through the RCD why I can not out on, keeps coming down

 

[sparkyspike]

Dual RCD boards have two separate neutral bars - sometimes supplied with a link between the two. Can you get a photo of this? I would say you either have the 80A RCD wired into the same neutral bar as the 63A one (maybe the link was never taken out?) or you have a faulty RCD.

the breaker is off and nothing going through the RCD why I can not out on, keeps coming down

Don't forget that the breaker only disconnects the live. The neutral and earth will still be connected, so an earth-neutral fault can still trip the RCD.

 

[bongos]

Did you manage to sort out these earlier RCD faults you posted about with the same board?

//www.diynot.com/forums/viewtopic.php?t=164435

//www.diynot.com/forums/viewtopic.php?t=164759

I seem to remember you said that you installed the CU yourself. Did the test results give an idea of any problems with the existing wiring when you changed it? Did a spark come out in the end and certify it anyway and if so did he find any problems with the wiring?

If you are having alot of problems with nusiance RCD tripping it might be a good time to call out a spark if one hasn't been involved yet!

 

[JohnD]

I will upload some pics,

looking forward to it.

 

[sparkyspike]

Definitely time to get an electrician in. No point guessing what the problem is - just get it fixed by someone who knows what they're doing. Seriously, it's the best course of action.

 

[Zehroni]

Dear All,
Many thanks for all of you who took the time to give advice and help. Just to put you in the picture.
It is the same CU that I installed and the first problem was sorted out by connecting one the neutral to the right side of the of the RCD as the CU is dual RCD, I could not see it at the time as it was dark, it was sorted out in the morning of the following day. Consequently and acting on one of your advice I called LEC electrics who inspected the installation and carried out a periodic test and reached the same conclusion I reached. There is a fault in one of the wires that completes the ring of down stairs sockets. They eliminated the wire and connected the socket of setting room radialy on 32A and the socket in the dining room radily on anther 32A. As soon as they left the RCD start tripping. I disconnected both sockets from the CU, changed the RCD and installed the only single socket by the CU which worked from 10 days. Some of the discussions on this form enabled me to inspect the socket again and the wire, I carried out continuity test on it and found nothing wrong with it. However, when I disconnected the wire completely from the CU, I could put the RCD up and stays up. I changed that piece of wire, connected the single socked and it has been working ok for the last couple of days. I conclude the wire was faulty.
The wires that connected to the dining and setting room are under the floor which is concrete, therefore, I could not flow, but my and LEC continuity test show that there is nothing wrong with them. However, I rewired the setting room today and it has been working O.K so far. I can only assume that the wires under the concrete have deteriorated, and if this conclusion is correct then I will rewire the dining room next weekend. At the moment the single socket by the CU is feeding the appliance in the dining room.

Thanks

 

[flameport]

Breaking a 32A ring into 2x 32A radials is unsafe - the cables won't be individually rated to 32A.

A continuity test will tell you nothing about the condition of the wires.

Randomly changing RCDs and removing pieces of wire is NOT the way to ensure your installation is safe.

Please post some pictures of this installation.
//www.diynot.com/forums/viewtopic.php?t=129539

 

[Zehroni]

Dear flameport,
I agree I will down grad them to 16A each and post a pic

 

[sparkyspike]

There is no point in seeing how long an RCD will last without tripping as a means of testing, because earth faults can be intermittent and accumulative. You need to use an insulation resistance tester to test your cables - not a continuity tester. Also you need to use an RCD tester to confirm the correct operation of the RCD.

However, I still suspect that there is a problem with the installation of the CU. A photo would be really useful.

 

[securespark]

I agree. If you cannot post pictures, we will find it almost impossible to help you.