Hot tub tripping, but also working… crossed Neutral?

[Refinedgent]

View attachment 310477

Thanks Bernard, that’s one issue solved. Switch will now function!
Looks like now just need to swap black (Earth) and grey (Neutral) and then move Brown (live) to LINE 2 instead of LINE 1

 

[EFLImpudence]

Looks like now just need to swap black (Earth) and grey (Neutral) and then move Brown (live) to LINE 2 instead of LINE 1

If the RCD does not trip (assuming it is functioning correctly) now that you have connected it properly, the neutral and earth cannot be the wrong way round so some investigation is required to determine which is actually which and not just relying on the colours.

 

[pcaouolte]

Would anyone actually want to get into this tub when it is full of water without having it properly tested for electrical safety?

 

[Refinedgent]

If the RCD does not trip (assuming it is functioning correctly) now that you have connected it properly, the neutral and earth cannot be the wrong way round so some investigation is required to determine which is actually which and not just relying on the colours.

Have connected up RCD and wired in how the wires are supposed to be and it is indeed tripping, so I’m guessing a fault somewhere in the tub circuitry, which is odd as it appears to be functioning perfectly. I’ll get a sparks round to investigate, seems very odd as it’s working perfectly and apparently has been wired up this way for some years, thanks all

 

[bernardgreen]

Spa or Spark. Needs a competent electrical safety inspector to look and report on it. Earthing being the critical item.

Exporting the CPC ( Earth ) from the house to a pool of water outside the house can create a hazardous situation as the CPC may be at a different potential to the Ground, it often is a few volts different, not enough to be a hazard to a person in contact with both Ground and the water, Worst case it could be a difference high enough to give a fatal shock. In this case the RCD will NOT operate as the fault current is flowing in the CPC cable and therefore does not affect the RCD, also it cannot be switched off as there are no switches in the CPC wiring,

 

[EFLImpudence]

In this case the RCD will NOT operate as the fault current is flowing in the CPC cable and therefore does not affect the RCD, also it cannot be switched off as there are no switches in the CPC wiring,

What ?

 

[bernardgreen]

If Pdn ( potential between network Neutral and true Ground ) is high then the man gets a shock. Anyone lifting him out of the water would also get a shock.

 

[JohnW2]

What ?

I think bernard was talking about the ('rare') 'case' in which the 'fault current' was effectively rising upstream of the RCD due to a supply-side neutral fault.

Kind Regards, John

 

[EFLImpudence]

I think bernard was talking about the ('rare') 'case' in which the 'fault current' was effectively rising upstream of the RCD due to a supply-side neutral fault.

I must be missing something, or

is it 'blue moon' time rather than related to this thread where the CPC appears wrongly connected and there is another RCD farther upstream?

If it is not related then why is the CPC connected to the water?

 

[JohnW2]

I must be missing something, OR
is it 'blue moon' time rather than related to this thread where the CPC appears wrongly connected and there is another RCD farther upstream?

I thing it's probably a case of your "or".

It would seem that Bernard's post #20 (to which you responded) was nothing specifically to do with this thread, per se, but, rather 'the usual' about the potential hazards of outdoor electrical things in the presence of a 'neutral fault' ('lost neutral') in a TN-C-S supply network.

Kind Regards, John

 

[bernardgreen]

If it is not related then why is the CPC connected to the water?

The sketch is basic, perhaps I should have added finer details

The CPC form the house is almost certainly connected to the metal parts of the tub. One or more of those metal parts are likely to be pipes \ pumps \ heater in contact with the water.

It is a bit like garden tools not being connected to the CPC in case the potential on the TN-C-S CPC becomes hazardous.

 

[bernardgreen]

It would seem that Bernard's post #20 (to which you responded) was nothing specifically to do with this thread,

It was specific to this post to explain to the OP that there are serious risks when DIY electrical work is performed without knowledge that is essential to make the installation a safe installation.

 

[ericmark]

1) There is no point having a 30 mA RCD feeding a 30 mA RCD. Except the one in the consumer unit does not display which type it is and the one on its own is a type A, but for a heater type AC is good enough.

2) You have still not indicated type of supply, is it TN-C-S (PME) or TN-S or TT? It makes a huge difference.

3) The connections L1, L2, L3 point to being designed for a three phase supply, you may be able to configure for single phase, but not really what one should try doing using a forum.

So what I said to start with, get an electrician.

 

[JohnW2]

It was specific to this post to explain to the OP that there are serious risks when DIY electrical work is performed without knowledge that is essential to make the installation a safe installation.

If you want to put it like that. I would call it a 'general' point (with which, as you will imagine, I don't disagree), since it is no way 'specific' to the OP's question/situation - and I was merely responding to EFLI's implied question about its relevance to this particular thread.

Your point is also probably not relevant if the OP's supply is not TC-N-S, since a dangerous N-E pd is then incredibly improbably (much more improbable than with TN-C-S, which is rare enough!).

Kind Regards, John

 

[ericmark]

Your point is also probably not relevant if the OP's supply is not TC-N-S, since a dangerous N-E pd is then incredibly improbably (much more improbable than with TN-C-S, which is rare enough!).

The point is @Refinedgent has not stated if TN-S, TT, or TN-C-S and if he does not know, then not safe for him to do the work.