RCD (sometimes) trips on switching OFF an ELO

[pushrod]

For the electrics of my kitchen renovation project I will now replace the RCD as a matter of course - it is 4-5 years old anyway. But that cannot be the problem..

I am NOT doing anything to the Consumer Unit. As I thought I had made clear -

All i did was read your earlier post and the rcd cannot be the problem

testing components that can be demonstrated to be operating satisfactorily is a red herring.

So you know that your rcd is tripping at the correct current You know that all your insulation resistances and continuities are all ok and within acceptable limits You know there are no N/E faults anywhere. You know if there are other earth leakage currents or even if your cooker has one

Well you obviously don't need any advice from me!
I wonder why i have £1000+ of testing kit

 

[nickblake]

The more i think about it the more i feel that the polarity from the cooker point to the oven in the wrong way round , thus switching the neutral this will cause random tripping of the RCD

 

[telectrix]

yeah , nick, but i think it was stated that the tripping iccured when the cooker isolator was switched off, and that's double pole.

 

[MarkieSparkie]

I believe the problem here is likely to be at the distribution unit. Most likely the cooker circuit neutral has been incorrectly terminated in the RCD side neutral bar, allowing switching transients to impress, common mode, an out of balance current which adds to the quiescent leakage of the RCD controlled circuits and thus tripping the RCD. The slightly random nature of the tripping action is cause by the point on the sine-wave cycle at which the switching action takes place, i.e. near either peak cause tripping but near the cross-over does not.

 

[charlhu]

I believe the problem here is likely to be at the distribution unit. Most likely the cooker circuit neutral has been incorrectly terminated in the RCD side neutral bar, allowing switching transients to impress, common mode, an out of balance current which adds to the quiescent leakage of the RCD controlled circuits and thus tripping the RCD. The slightly random nature of the tripping action is cause by the point on the sine-wave cycle at which the switching action takes place, i.e. near either peak cause tripping but near the cross-over does not.

Thank you for the thoughtful post and I followed up your idea. Unfortunately, if you check out my latest post today and attached photos I think you might be satisfied that the cooker circuit neutral is correctly terminated on the non-rcd side of the neutral busbar.

 

[sparkinlee]

...if you check out my latest post today and attached photos...

I must be missing something - I can't see a post with photos attached. Can you point me in the right direction?

 

[charlhu]

Thank you for the thoughtful post and I followed up your idea. Unfortunately, if you check out my latest post today and attached photos I think you might be satisfied that the cooker circuit neutral is correctly terminated on the non-rcd side of the neutral busbar.

NB: The post is a new thread.

 

[charlhu]

I must be missing something - I can't see a post with photos attached. Can you point me in the right direction?

To make attachments I had to start a new thread which i completed just a couple of minutes ago

 

[charlhu]

yeah , nick, but i think it was stated that the tripping iccured when the cooker isolator was switched off, and that's double pole.

I have started a new thread with attachments updating the facts.

 

[charlhu]

The more i think about it the more i feel that the polarity from the cooker point to the oven in the wrong way round , thus switching the neutral this will cause random tripping of the RCD

I have started a new thread with attachments updating the facts.

 

[charlhu]

Jah, das shmekt immer gudt!

Touché.
I have started a new thread with attachments updating the facts.