Commando v Wall Charger

[The Baron]

Hi All,

I'm waiting delivery of my M3P and looking into charging at home.

Without sounding like an idiot what are the benefits of having a wall charger fitted over a 32A commando socket ?

I have a single phase 63A supply at home, do I need to swap the fuse out for a 80A or 100A one or will the 63A do the job ok ?

Thanks

 

[TheEVadvisor]

100 amp would be better and you should be able to request the upgrade for free. home charger is just quicker to plug in and should offer high speed of charge

 

[The Baron]

100 amp would be better and you should be able to request the upgrade for free. home charger is just quicker to plug in and should offer high speed of charge

thanks for the reply, wouldn't the 32A commando give the same charge a wall charger 7 kw ?

 

[Roy W.]

thanks for the reply, wouldn't the 32A commando give the same charge a wall charger 7 kw ?

It would, but it also means you’d be using the “granny cable” that comes with the car all the time, and you’d need to buy the 32A Commando adapter from Tesla.

Also your 32A commando would need to be installed with the same electrical protection as a charge point, so it’s not a cheap thing to do.

 

[Artiste]

I had a 32A commando socket installed because I’m not eligible for the £500 OLEV grant. I bought my own cable so I didn’t need to buy the 32A adapter and can keep the Tesla supplied cable in my car. It charges at the same speed as a 7KW charge point. I did not tell my electrician it was for an EV so it’s not wired in according to 18th Regs that came into force at the beginning of last year with all the extra expense involved. It was considered safe before then and I’m quite satisfied it’s safe now.

If you are entitled to the OLEV grant then I would suggest a wall mounted charge point is the best way to go. If, however, that isn’t possible for you rest assured that a 32A commando socket will work perfectly. Some people frown on the idea of using a commando socket as a permanent solution but I’ve never been able to work out why.

 

[Mr Miserable]

Without sounding like an idiot what are the benefits of having a wall charger fitted over a 32A commando socket ?

This is a question that has been asked before (search through the threads) and there are some excellent replies from people who know what they are talking about.
The answer is there is no advantage to having a 32A commando socket - only disadvantages, with electrical safety being one of them.

 

[Glan gluaisne]

I had a 32A commando socket installed because I’m not eligible for the £500 OLEV grant. I bought my own cable so I didn’t need to buy the 32A adapter and can keep the Tesla supplied cable in my car. It charges at the same speed as a 7KW charge point. I did not tell my electrician it was for an EV so it’s not wired in according to 18th Regs that came into force at the beginning of last year with all the extra expense involved. It was considered safe before then and I’m quite satisfied it’s safe now.

If you are entitled to the OLEV grant then I would suggest a wall mounted charge point is the best way to go. If, however, that isn’t possible for you rest assured that a 32A commando socket will work perfectly. Some people frown on the idea of using a commando socket as a permanent solution but I’ve never been able to work out why.

Just to be clear, the 18th Ed of BS7671 didn't really change anything as far as EV charge points are concerned - all it did was sweep up a long standing separate set of guidance from the IET, so that everything related to EV charge points was in a single document, rather than two separate ones.

By the same token, the guidance to not export a TN-C-S/PME PE to an external power point used to power largely metal structures (like a caravan, metal framed shed, metal greenhouse etc) has been around a long time, and the requirements to provide a similar level of protection for an electrically connected, largely metal bodied car is just keeping in line with that.

There's no good reason why a properly installed, switched commando outlet shouldn't be as safe as a wall charger, really. The main objection is really that the UMC supplied with the car may not be intended for continuous daily use and may get a bit bashed around, plus it's a slightly less convenient solution, having to get the UMC out and plug it in at both ends.

 

[Artiste]

This is a question that has been asked before (search through the threads) and there are some excellent replies from people who know what they are talking about.
The answer is there is no advantage to having a 32A commando socket - only disadvantages, with electrical safety being one of them.

This is a question that has been asked before (search through the threads) and there are some excellent replies from people who know what they are talking about.
The answer is there is no advantage to having a 32A commando socket - only disadvantages, with electrical safety being one of them.

There may be no advantage if you can access the OLEV grant. There is a clear price advantage if you can’t, or if you don’t like the fact that in many cases the £500 grant seems to disappear straight into the back pockets of the installers.

No one has ever explained to me why a properly installed commando socket should be any less safe than a charge point. My electrician, who I’ve known for years, is perfectly satisfied that my installation is safe.

 

[Artiste]

Just to be clear, the 18th Ed of BS7671 didn't really change anything as far as EV charge points are concerned - all it did was sweep up a long standing separate set of guidance from the IET, so that everything related to EV charge points was in a single document, rather than two separate ones.

By the same token, the guidance to not export a TN-C-S/PME PE to an external power point used to power largely metal structures (like a caravan, metal framed shed, metal greenhouse etc) has been around a long time, and the requirements to provide a similar level of protection for an electrically connected, largely metal bodied car is just keeping in line with that.

There's no good reason why a properly installed, switched commando outlet shouldn't be as safe as a wall charger, really. The main objection is really that the UMC supplied with the car may not be intended for continuous daily use and may get a bit bashed around, plus it's a slightly less convenient solution, having to get the UMC out and plug it in at both ends.

The most helpful and sensible post I’ve read about commando sockets!!

I appreciate your comments about wear and tear. I bought a dedicated lead so I could leave the Tesla supplied lead in the car. This cable is permanently plugged into an IP67 interlocked commando socket, and it is secured by four P-clips at the socket end so there is absolutely no movement at the socket. The rest of the cable is wound round a cable tidy with a socket to hold the “gun”. It works perfectly for me!

 

[Adopado]

The most helpful and sensible post I’ve read about commando sockets!!

I appreciate your comments about wear and tear. I bought a dedicated lead so I could leave the Tesla supplied lead in the car. This cable is permanently plugged into an IP67 interlocked commando socket, and it is secured by four P-clips at the socket end so there is absolutely no movement at the socket. The rest of the cable is wound round a cable tidy with a socket to hold the “gun”. It works perfectly for me!

Yes, I would quite happily operate in that mode so long as I had the extra UMC to leave permanently in place. I would suggest you probably get a higher level of reliability not having to take account of "smart" features!

 

[Artiste]

Yes, I would quite happily operate in that mode so long as I had the extra UMC to leave permanently in place. I would suggest you probably get a higher level of reliability not having to take account of "smart" features!

Yes, it’s as dumb as a box of rocks and has been 100% reliable!

 

[Type2]

This is a question that has been asked before (search through the threads) and there are some excellent replies from people who know what they are talking about.
The answer is there is no advantage to having a 32A commando socket - only disadvantages, with electrical safety being one of them.

There are certainly some advantages. A commando socket costs much less if you can’t get the OLEV grant, it has a much smaller footprint, and it’s a lot easier to remove and take with you if you move house, as I will be shortly. I’ve been charging with a commando socket for four months without a single problem.

Why is a competently installed commando socket any less safe than a wall charger?

 

[Glan gluaisne]

Why is a competently installed commando socket any less safe than a wall charger?

It isn't, as witnessed by all the thousands of caravan pitches set up with commando outlets and TT earthing, with a suitable RCD/RCBO in the outlet box.

The problem comes with commando outlets (or any outdoor outlet for that matter) that are not competently installed, and sadly there are an awful lot of poor outdoor installations. Apart from the obvious risks associated with stuff getting wet, the main issue is one of a difference between the earth potential of the earth connection in the outlet and the "true" earth that someone outside is standing on.

This problem arises because the protective earth (PE) in most newer houses (those built in the past 40 to 50 years or so) have the PE provided on the incoming cable, either as a separate PE conductor or combined with the neutral (when it's called a PEN conductor). If there is a fault in the supply, then this incoming "earth" can be at a potential that is significantly higher than the "true" earth that someone outside is standing on. The result is that something metal that's connected to the incoming earth could be sitting at a high voltage relative to the potential on the local earth and present an electric shock risk.

Disconnecting the incoming supply PE from the outdoor outlet, and providing separate earth protection for it using a local earth electrode with an RCD/RCBO, significantly reduces this risk, as if there is an incoming PEN or PE fault then the earth potential of any exposed metal will remain very close to the local earth potential, so there's a much reduced electric shock risk.

 

[The Baron]

Thanks for all the replies very much appreciated.

 

[D4v1d]

The most helpful and sensible post I’ve read about commando sockets!!

I appreciate your comments about wear and tear. I bought a dedicated lead so I could leave the Tesla supplied lead in the car. This cable is permanently plugged into an IP67 interlocked commando socket, and it is secured by four P-clips at the socket end so there is absolutely no movement at the socket. The rest of the cable is wound round a cable tidy with a socket to hold the “gun”. It works perfectly for me!

could you post a link where you got the 32amp to type 2 lead from? thank you

 

[Avendit]

The problem comes with commando outlets (or any outdoor outlet for that matter) that are not competently installed,

/Waves from the side lines/

I self installed a 16a commando as a temp solution as the wall a real charger will go on isn't built yet. But that process has started now so my reliable-and-didn't-kill-any-one-in-3-months commando has been ripped out.

Size isn't really a pro any more, the EO Pro isn't much bigger than a commando. That's my latest plan.

And thanks again to @Jeremy Harris who continues to educate us all on this stuff!

 

[DaddyCool]

Im sceptical re the 'smarts' being based in the charger vs the car and so far the sparkies have been far from prompt or helpful in breaking down their quotes between charger/labour/parts to allow me to compare for the ELOV grant.
As Im likely to be mostly charging at work for free (well, ChargePlace Scotland - £20 p.a.) im hardly going to be charging at home much. Wonder if one of these bad boys will do the trick? (inside garage)

https://www.screwfix.com/p/abb-socket-32a-2p-e-250v-ip44-w-25a-rcd/9624f
Industrial RCD Socket IP67 240V 32A 30ma 2P+E Switched

 

[Avendit]

blue should be 16A I thought, which means something is up with those ones that I am way under qualified to advise on...

Successful charge, possibly. Safe for you and your car? not so sure. As my EE lecturer used to say, "volts jolt, milliamps kill you really f'ing dead"

 

[DaddyCool]

blue should be 16A I thought, which means something is up with those ones that I am way under qualified to advise on...

Successful charge, possibly. Safe for you and your car? not so sure. As my EE lecturer used to say, "volts jolt, milliamps kill you really f'ing dead"

Mine used to say k k current k k kills
I thought Blue was for single phase

 

[NorfolkMustard]

colour roughly denotes voltage range IEC 60309 - Wikipedia