New shed circuit tripping RCD at house consumer unit

[Octopus]

If the RCD in the summer house is tripping its more than likely one of the circuits from the summer house CU is faulty.............

EDIT : Old thread alert.

 

[Pauldicker]

If the RCD in the summer house is tripping its more than likely one of the circuits from the summer house CU is faulty.............

I took them all out and put one circuit in at a time then took it out and tried the next one. each one tripped. Its possible that theres water intrusion somewhere but not on every circuit, but it does mean ripping out the garden and decking.

 

[Octopus]

I took them all out and put one circuit in at a time then took it out and tried the next one. each one tripped.

That's not the way to go about fault finding..... when you say "took them out" - what did you take out?

 

[Pauldicker]

That's not the way to go about fault finding..... when you say "took them out" - what did you take out?

I removed each mcb after isolating the supply then reconnected one mcb at a time. Trying to narrow it down.

 

[Octopus]

I took them all out and put one circuit in at a time then took it out and tried the next one. each one tripped. Its possible that theres water intrusion somewhere but not on every circuit, but it does mean ripping out the garden and decking.

The only thing you should be getting out is your MFT, a pad and a pen....

 

[Octopus]

I removed each mcb after isolating the supply then reconnected one mcb at a time. Trying to narrow it down.

What do you mean by took out MCB? Did you just disconnect the live from the MCB?

 

[Pauldicker]

What do you mean by took out MCB? Did you just disconnect the live from the MCB?

Now the whole circuit L,N,E and tried each circuit on its own.(there are 4) water feature, disconnected pond, decking lights & summer house sockets.

 

[Octopus]

Hum ......... did you test the RCD?

You should always leave the CPC connected to the CU...

 

[Pauldicker]

Hum ......... did you test the RCD?

No i will probably do a ramp test when they get back from their hols in a few weeks. And an ir test on the swa feed in

 

[Pauldicker]

Hum ......... did you test the RCD?

You should always leave the CPC connected to the CU...

Its got to have been there 10-15 years. And working fine up until a month ago. So im thinking water somewhere.

 

[Octopus]

I would start by fully testing the RCD ...... then probably , test the sub main .....

Difficult to say on a forum, only you have seen the installation.....

 

[Pauldicker]

I would start by fully testing the RCD ...... then probably , test the sub main .....

Difficult to say on a forum, only you have seen the installation.....

Well 90% of it is hidden. But its always nice getting hepl and advice.

 

[Pauldicker]

I would start by fully testing the RCD ...... then probably , test the sub main .....

Difficult to say on a forum, only you have seen the installation.....

I have a spare wylex rcd in my garage so i may swap it and see if it mskes a difference aswell.

 

[Octopus]

Its unusual for a supply cable to affect an RCD but it does happen...

Garden electrics are such a pain ........... and hence why its best not to have them connected to a RCD which also protects house circuits..

 

[telectrix]

if it's the RCD in the summer house that's tripping, then it's 99.9% that the fault is downstream of that RCD. the feed to the summer house is not going to be the problem.

 

[Octopus]

I have a spare wylex rcd in my garage so i may swap it and see if it mskes a difference aswell.

Don't waste your time (and the customers money) swapping components UNTIL you have tested the RCD.............

 

[Pauldicker]

Its unusual for a supply cable to affect an RCD but it does happen...

Garden electrics are such a pain ........... and hence why its best not to have them connected to a RCD which also protects house circuits..

Well at least the installer got that right and did not put it on the house rcd

 

[Pauldicker]

Don't waste your time (and the customers money) swapping components UNTIL you have tested the RCD.............

Their good friends so wont charge them full rate.

 

[Pauldicker]

if it's the RCD in the summer house that's tripping, then it's 99.9% that the fault is downstream of that RCD. the feed to the summer house is not going to be the problem.

Its deffo an rcd fault then. As i cannot believe every circuit has a fault.

 

[Octopus]

Their good friends so wont charge them full rate.

Friends or not, you shouldn't be changing random parts unless your tests prove them to be faulty...............................