Problems with socket circuits

[Nijinski001]

Hi
I am having problems with the socket circuits in a house. Can you guys tell me what is wrong?

Scenario
Wylex CU with the following set up left to right. (Forgetting a couple of unused MCBs in the mix)
100A Main switch - 16a Lights MCB - 32a Upstairs sockets - gap - 32a lounge/diner/hall socket circuit - 32a kitchen utility socket circuit - 63A/30mA RCD.

Lights no problem.
Problem - All is okay with all sockets until someone plugs something into a socket upstairs and switches on. This trips the RCD. All MCBs remain in the 'on' position. The upstairs sockets phase wire is still live but nothing will work on any of them. As the other sockets are on the RCD side of the CU they don't work either,

Sockets were working fine last week and we can't pin down anything that may have happened to change the circuit consistency.

My first reaction is that this is a major earthing problem but where do I start to look?
Or could it be something else?
Shouldn't the RCD be to the left of the MCBs it is protecting? (As the main switch is to the left!)
How come the sockets don't work despite the phase still being live? (Getting continuity on both phase neutral and cpc)

 

[megawatt]

Can you post some photos of the CU wiring?

Also, has anything been done in the house lately which could cause problems (drilling walls, nailing floors)?

 

[Nijinski001]

Nothing has been done since last week. No drilling nailing or otherwise.

I am going to try to get digi photos today but need to borrow a camera.

The RCD trip indicates a break in the wiring or inbalance in current flow but I am getting continuity readings on both neutral and earth for that circuit.

Also can anyone tell me why a circuit is tripping the RCD when the apparently offending circuit is on the opposite side of the CU?

 

[megawatt]

It's difficult to say without either a diagram of the connections in the CU or some photos

 

[andy]

Also can anyone tell me why a circuit is tripping the RCD when the apparently offending circuit is on the opposite side of the CU?

phase might be on the non-RCD. doesnt mean the neutral is.

 

[Spark123]

Yup
Sounds like the neutral for the upstairs sockets could be in the wrong neutral bar in the CU.

16A for domestic lighting??

 

[Nijinski001]

Yup spark

Tell me about it. I didn't fit the box.
I think I'll be recomnmending some changes.

I don't remember the neutral being on the wrong side but I'll check.

This would cause an imbalance in the RCD wouldn't it?

 

[andy]

I don't remember the neutral being on the wrong side but I'll check.

This would cause an imbalance in the RCD wouldn't it?

yes