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Charging is tripping circuit breaker

OK. I see the text underneath now. But this is a single pole mains breaker. Two 40A and a 32A on the same circuit still draws more than the rated capacity of 63A (possible 72A). Regardless of the theoretical load capabilities of the circuit there is obviously a heavy load on the 2 x 20A circuits such that adding in the extra 32A is overloading the main breaker. The single pole main breaker in this case needs to be 80A minimum. It would be good to see the whole picture regarding this circuit layout as that one picture doesn't tell the whole story. Turn off the two 20A circuits and run the 32A alone just as a quick test. If the breaker trips its an earth leakage issue. If it works fine then it is an overload issue requiring a larger main breaker. Easy test.
It is not a "main breaker". It is an RCD that was added after. As it only provides protection for the two 20A (not 40A) power circuits there will be a main breaker (which covers all circuits) somewhere else.

The problem here is the electrician should NOT have wired the new 32A circuit through that RCD. He should have installed a separate breaker and RCD in one for the dedicated circuit.
 
It is not a "main breaker". It is an RCD that was added after. As it only provides protection for the two 20A (not 40A) power circuits there will be a main breaker (which covers all circuits) somewhere else.

The problem here is the electrician should NOT have wired the new 32A circuit through that RCD. He should have installed a separate breaker and RCD in one for the dedicated circuit.
Totally agree.
 
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20220325_124346.jpg

Apologies, it didn't attach in the previous post. I have a different sparky coming on Tues (for other stuff), have mentioned this to him so he'll take a look whilst here.
 

meloccom

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Apologies, it didn't attach in the previous post. I have a different sparky coming on Tues (for other stuff), have mentioned this to him so he'll take a look whilst here.
That looks like you have may an external electrical box, possibly on a post, in fact it looks very similar to mine. Do you also have a sub board inside your house?
 
Ok, the switch board is fairly old, the main switch is just a switch, it looks like the device right at the bottom is the fuse for the mains and is a 100amp HRC (High Rupturing Capacity)

With new residential installations and rewires all circuits require require RCD's but at the time the switch board was installed they were probably only required for power circuits, hence the 63 amp RCD labeled as being for circuits 1 and 2, and it may not be the original one fitted, a larger one may have been fitted when the air conditioners were installed which look like they were added at a later date (as power circuits they also have to be protected)

As the 63 amp RCD is the one tripping when the UMC is plugged into the 32 amp outlet, it would seem that the supply for its RCD is coming from the 63 amp RCD

As to why the 63 amp RCD is tripping instead of the one for the 32 amp outlet, it may more sensitive, or the leakage current in the other power circuits while less that a total of 30mA means that it is sensing more leakage current than the Outlet RCD

As to why the RCD is tripping it may be that the tail is faulty, or it could be that it adds enough extra leakage current which may be less than 30mA but means that the total leakage current across all the circuits connected to the 63 amp RCD now exceeds 30mA
 
As the 63 amp RCD is the one tripping when the UMC is plugged into the 32 amp outlet, it would seem that the supply for its RCD is coming from the 63 amp RCD

As to why the 63 amp RCD is tripping instead of the one for the 32 amp outlet, it may more sensitive, or the leakage current in the other power circuits while less that a total of 30mA means that it is sensing more leakage current than the Outlet RCD

As to why the RCD is tripping it may be that the tail is faulty, or it could be that it adds enough extra leakage current which may be less than 30mA but means that the total leakage current across all the circuits connected to the 63 amp RCD now exceeds 30mA
It would be pretty easy to check which of these cases is most likely.

If the 63A RCD is the ONLY thing that trips when the 32A UMC tail is powered AND the 32A UMC tail is no longer powered, the 32A circuit is almost certainly running through the 63A RCD.

If the 63A RCD is the ONLY thing that trips BUT the 32A tail and UMC keeps powered, then the 32A circuit is not running through the 62A RCD and it is probably accumulative current leakage.

If the new unmarked 32A RCBO is also tripping and cutting the power, then the 32A tail is probably faulty.

Turning off the unmarked 32A RCBO and seeing if the UMC with 32A tail still works would also be an interesting test.

It is also possible the electrician accidentally pulled the input for the 32A RCBO from the output of 63A RCD so they are in series and the 63A RCD is more sensitive.
 
Thanks everyone for the advice and interest. An update, (different) electrician came round and had a quick look at it. I'll describe best as possible (to my the
It is also possible the electrician accidentally pulled the input for the 32A RCBO from the output of 63A RCD so they are in series and the 63A RCD is more sensitive.
Thanks all for the feedback and response.

Update today: an (different) electrician came round and had a look. From my limited understanding of what he described, @atj777 banged the issue on the head. Took a couple minutes to fix. Have tried charging at various speeds and all seem to be working.
 

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