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Discuss Type C MCB needed for EV Charging? in the Electrical Forum area at ElectriciansForums.net

Marcus Vaughan

Regular EF Member
Hi all,

I've not a lot of experience with EV but was called to a local job to investigate a loss of power to a 32amp 7.2KW EV charger.

It turned out the 32A MCB (Type B) had failed, and would not even operate when completely removed from the board.

I happened to have a matching Contactum B32 breaker (2nd hand) - so put that in to literally 'get them back on the road'.

Anyhow - the customer then tells me he has been advised that the breaker should be a type C.

I've not heard of this before, and the manufacturer was fairly non-committal "You can put in a type C if you want"

Can anyone advise if EV chargers are susceptible to inrush due to the transformer?

It's a Rolec EVHomecharge http://assets.rolecserv.com/files/products_document/69fae0ff545e38d3a5de7cda8d5547ae/WallPod EV Tethered Data Sheet - 02.pdf

I wonder what other peoples experiences of this issue is?

No problem with changing to a type C in terms of Max Zs etc.

...but not an easy part to replace if I am going to stick to the same manufacturer. Breaker on the left is what I have put in - but I can't find a contactum 7 series type C anywhere. I think I've got a 9 series though.

upload_2019-4-13_9-41-3.png

Installation details,
TNS
Ze=0.12 ohms
circuit length is only a couple of meters in SWA - R1+R2 = 0.03 ohms
40A 30mA RCCB at the charging point.
No faults.

The old MCB was of poor quality and nearly split in two with over - tightening. I think there has been frequent tripping and resetting.

Thoughts? Type C standard practice for EV?

Cheers.
 

buzzlightyear

please let me back in to the prison cell.
Electrician's Arms
Don't worry about buying the actual charging unit at this stage. To do the notification under your current scam membership, just add a new 32A circuit on a Type C MCB/RCBO at the DB and terminate to a rotary isolator next to where the charging point will go if & when you buy .
that was posted about 45mins a go by a fellow spark .
 

Marcus Vaughan

Regular EF Member
Don't worry about buying the actual charging unit at this stage. To do the notification under your current scam membership, just add a new 32A circuit on a Type C MCB/RCBO at the DB and terminate to a rotary isolator next to where the charging point will go if & when you buy .
that was posted about 45mins a go by a fellow spark .
Just spotted that - cheers.
 

buzzlightyear

please let me back in to the prison cell.
Electrician's Arms
Devon Chris why is that bad spelling, when I copied and paste it from the forum and from tony Michell?:mad::mad:
 

Gavin John Hyde

Electrician's Arms
CCTV / Alarms
The rolec ev chargers usually have a 40 amp type c rcbo in them for a 32 amp charge / 20 amp rcbo for a 16 amp charge load.
When i discussed this on a training day they were non commital about the supply mcb. They did say with a short cable run there tech people found more nuisance tripping. With longer cable runs less so. But a type c is a safer bet. With the earlier rolec units it was rebadged chint and quality was iffy the newer ones are much better.
Guess its a case of cable calcs and circuit design.
Personally i would always install type c mcb. If i have to install an upfront type a rcd for the evbox elvi charger then i use a rolec rcbo with type a protection and 40amp type c to protect the charger as the internal dc monitoring in the charger doesnt on its own meet regs. Rolec only charge around 20 quid for these too which is a good price.
 

Marcus Vaughan

Regular EF Member
The rolec ev chargers usually have a 40 amp type c rcbo in them for a 32 amp charge / 20 amp rcbo for a 16 amp charge load.
When i discussed this on a training day they were non commital about the supply mcb. They did say with a short cable run there tech people found more nuisance tripping. With longer cable runs less so. But a type c is a safer bet. With the earlier rolec units it was rebadged chint and quality was iffy the newer ones are much better.
Guess its a case of cable calcs and circuit design.
Personally i would always install type c mcb. If i have to install an upfront type a rcd for the evbox elvi charger then i use a rolec rcbo with type a protection and 40amp type c to protect the charger as the internal dc monitoring in the charger doesnt on its own meet regs. Rolec only charge around 20 quid for these too which is a good price.
Thanks for that detailed reply. Good information. It seems to make sense to go with a type C if I can find one, and the circuit is very short.
 

buzzlightyear

please let me back in to the prison cell.
Electrician's Arms
CONTACTUM MCB CPB RANGE ALL AMP TYPES SP Circuit Breaker C TYPE - *FREE P&P* FLIE BAY .
 

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