Replacing a 32A type B RCD

[SpecialK]

Hi,
This type B RCD has failed. No power coming out even though it's on. The test button also doesn't work. It feeds an EV outlet.
There doesnt appear to be an easy to find replacement? Can anyone assist with a replacement part?

Also the wires coming off the tail splitters are 4mm but sleeved. Is this OK?

Thanks

 

[Adam_151]

Type B RCD is a little misleading - Thats a double pole RCBO, the RCD part of which is type A, and the Overucrrent part is a Type B/B curve 32A.

How have you proved that it is faulty?

 

[jurassic sparkk]

This type B RCD has failed. No power coming out even though it's on.

What made you think that? Type B RCD?

 

[SpecialK]

My quick Google said it was type B but that wasn't on the manufacturers website.

Schneider - Multi 9 - MGN19767 - DCP H Vigi - 32a 30mA Type B Double Pole RCBO New​

Checked there was power in at the top and nothing coming out the bottom with a meter. Test switch doesn't work either.

Any other checks I can do?

Any thoughts on a replacement? Maybe searching type a will yield more results...

 

[Adam_151]

RCD type symbols:

https://www.cef.co.uk/catalogue/products/4946310-32a-double-pole-2-module-b-curve-10ka-30ma-type-a-mini-rcbo

Do you have anyway to isolate it?

 

[JohnW2]

What made you think that? Type B RCD?

Well, as has been said, it's an RCBO, the over-current part of which is "B32" - and, until pretty recently, virtually everyone described B-curve MCBs and RCBOs at "Type B". Indeed, even the latest amendment of BS7671 still does (e.g. in Table 41.3).

Then someone with seemingly very little brain decided that we would use "Type B" (along with Types A, AC and F) to mean something total different in relation to these devices. I suppose we should be a little grateful that the ambiguity only relates to "Type B" (since, to the best of my knowledge, devices with A, AC and F curves don't exist) but that's not a lot of consolation to those who have been confused by "Type B"

 

[SpecialK]

RCD type symbols:

https://www.cef.co.uk/catalogue/products/4946310-32a-double-pole-2-module-b-curve-10ka-30ma-type-a-mini-rcbo

Do you have anyway to isolate it?

Hopefully. It feeds from the meter in to a Tesla power wall gateway. Looks like isolating at the gateway will remove the power. Are the 4mm(?) cables from the Henley's to this unit OK as they are essentially fused by the 100A cutout?

 

[Murdochcat]

On the plus side you don’t have to fit the same make , so as long as it’s a double pole 32A RCBO type A you can crack on BUT your main issue appears that you have no way to isolate the supply to this enclosure and working live is not an option

 

[SpecialK]

https://www.cef.co.uk/catalogue/products/4946310-32a-double-pole-2-module-b-curve-10ka-30ma-type-a-mini-rcbo

Are MCG a decent brand?

 

[Adam_151]

Hopefully. It feeds from the meter in to a Tesla power wall gateway. Looks like isolating at the gateway will remove the power.

I thought it fed an EVSE? But how are you going to isolate it from the incomming electricity supply?

Are the 4mm(?) cables from the Henley's to this unit OK as they are essentially fused by the 100A cutout?

Possibly - but err, not really; I've just looked more closely, they looked to be bigger than that, so I didnt look too closely, but now see that they are 4mm singles in pvc oversleeve, which fits poorly at the henley block end, thats not great, the basic insulation is on show and the terminal is likely accessible round the sides of the conductor. As to 4mm protected by a 100A fuse, its only got to provide fault protection (the 32A RCBO provides overcurrent protetcion), I think normally if you do the calculation, in most cases 4mm is just acceptable for thermal withstand. Personally considering it is what, a foot or so, I'd have them out and put 16mm tails in, and terminate them properly at the henleys

 

[Adam_151]

Are MCG a decent brand?

They are a resonable budget brand. Top money would be schneider acti-9 stuff , now it wouldn't be for me to say if the premium you pay would translate into better quality....

 

[SpecialK]

They are a resonable budget brand. Top money would be schneider acti-9 stuff , now it wouldn't be for me to say if the premium you pay would translate into better quality....

I will keep looking to find a decent brand. Struggling though as I might be searching the wrong terms

 

[SpecialK]

I thought it fed an EVSE? But how are you going to isolate it from the incomming electricity supply?



Possibly - but err, not really; I've just looked more closely, they looked to be bigger than that, so I didnt look too closely, but now see that they are 4mm singles in pvc oversleeve, which fits poorly at the henley block end, thats not great, the basic insulation is on show and the terminal is likely accessible round the sides of the conductor. As to 4mm protected by a 100A fuse, its only got to provide fault protection (the 32A RCBO provides overcurrent protetcion), I think normally if you do the calculation, in most cases 4mm is just acceptable for thermal withstand. Personally considering it is what, a foot or so, I'd have them out and put 16mm tails in, and terminate them properly at the henleys

It goes from cutout to meter then up to the Tesla gateway. Then down to Henley blocks which split to the EV supply and a fused 100A switch which the goes to the house CU.

Hopefully isolating at the gateway will allow it to be changed out...

 

[Risteard]

EVSEs generally shouldn't be supplied from a 32A protective device. A 40A is far more appropriate as you do not want a device operating at its full rated capacity for many hours at a time.