32A Commando Socket for 7kW charging
Discussion
The cost of home charge point installation is proving prohibitive for me just now. I just got my latest quote - £1,250! Bonkers for what is effectively a plug socket with some basic WiFi connectivity.
There's plenty of sources out there who will point you to the Tesla UMC (mobile / granny charger) which can be used in conjunction with a 32A 'Commando' adapter and will subsequently charge at 7.4kW - the same rate as a dedicated Type 2 EVSE.
However, there's some interpretation of the updated British Standards which dictate that you must also install separate PEN-fault detection and a Type B RCD, which adds around £300 to the installation.
I've reached out to a number of electricians and two have said that they can't do it as it "breaks regs" (regulations). The regulations seem very OTT, especially when this kind of setup was acceptable 18 months ago, but now is not?
What's the real risk here? The house likely won't burn down. The car isn't going to explode. Any hiccup in the supply to the car and the car itself will interrupt the charging.
The socket location is sheltered from the elements, entirely closed in. I would make sure to get an interlocking type of socket, so no power if nothing is plugged in.
I'm tempted to just ring up and tell the installers that it's for a caravan or hot tub, then park the Tesla around the corner during installation! Does anyone have any insight?
There's plenty of sources out there who will point you to the Tesla UMC (mobile / granny charger) which can be used in conjunction with a 32A 'Commando' adapter and will subsequently charge at 7.4kW - the same rate as a dedicated Type 2 EVSE.
However, there's some interpretation of the updated British Standards which dictate that you must also install separate PEN-fault detection and a Type B RCD, which adds around £300 to the installation.
I've reached out to a number of electricians and two have said that they can't do it as it "breaks regs" (regulations). The regulations seem very OTT, especially when this kind of setup was acceptable 18 months ago, but now is not?
What's the real risk here? The house likely won't burn down. The car isn't going to explode. Any hiccup in the supply to the car and the car itself will interrupt the charging.
The socket location is sheltered from the elements, entirely closed in. I would make sure to get an interlocking type of socket, so no power if nothing is plugged in.
I'm tempted to just ring up and tell the installers that it's for a caravan or hot tub, then park the Tesla around the corner during installation! Does anyone have any insight?
I don't have any useful insights, but I had a 32A Commando socket installed 2 years ago to charge my Tesla - I figured I didn't need a smart charger as the car was the smart bit.
I've never had an issue with it, works perfectly.
Have regulations changed recently to ensure people only have smart chargers installed for EV's? Not sure, but it rings a bell.
I've never had an issue with it, works perfectly.
Have regulations changed recently to ensure people only have smart chargers installed for EV's? Not sure, but it rings a bell.
Did my 32a commando socket myself inside the garage, with the TMC trailing under the door.
I had a spare way in the consumer unit further along the same wall and some spare 10mm cable, the switched commando socket was 25 quid.
Tightened every terminal everywhere, leaving the DNO terminals around the meter as the only weak point.
Worked fine on the Tesla for two years. We have a 100a main fuse and a split consumer unit with rcds.
ETA do read this though - that’s why I said on mine the weak point could well be the bits I can’t legally check.
https://www.speakev.com/threads/a-cautionary-tale-...
I had a spare way in the consumer unit further along the same wall and some spare 10mm cable, the switched commando socket was 25 quid.
Tightened every terminal everywhere, leaving the DNO terminals around the meter as the only weak point.
Worked fine on the Tesla for two years. We have a 100a main fuse and a split consumer unit with rcds.
ETA do read this though - that’s why I said on mine the weak point could well be the bits I can’t legally check.
https://www.speakev.com/threads/a-cautionary-tale-...
Edited by andy43 on Saturday 13th August 09:16
I'm thinking about getting this setup and a 32a socket put in at home.
https://www.evconnectors.com/product/juice-booster...
This would cover every single charging option in one bit of kit, including outside the UK/ trips away from home.
What am I missing over a standard wall charger, I don't need any smart stuff as the cars already do all I need.
The 32a socket would be inside the garage with the charger and the cable will just go under the door as the granny charger does now.
https://www.evconnectors.com/product/juice-booster...
This would cover every single charging option in one bit of kit, including outside the UK/ trips away from home.
What am I missing over a standard wall charger, I don't need any smart stuff as the cars already do all I need.
The 32a socket would be inside the garage with the charger and the cable will just go under the door as the granny charger does now.
Edited by TheRainMaker on Saturday 13th August 11:18
Nothing wrong with a 32A socket as long as it is properly installed.
Refering to the 'Notes for Electricians' for the Ohm charger for instance, it recommends that any 32A outlet is installed "where expected to charge an EV outside" to the same rules as a full EVSE.
Simply install the 32A outlet with a decent ground spike. (TT earthing).
40A RCBO for cable protection (assuming cable is good for 40A+)
Refering to the 'Notes for Electricians' for the Ohm charger for instance, it recommends that any 32A outlet is installed "where expected to charge an EV outside" to the same rules as a full EVSE.
Simply install the 32A outlet with a decent ground spike. (TT earthing).
40A RCBO for cable protection (assuming cable is good for 40A+)
i think load balancing is the big consideration. depends how your house is powered. if you run electric showers and cooking (and roof hemp farm 
) and then try and run a 'dumb' 32a commando to a car, it's going to be providing full current for a good while if your EV battery is low, so the chances of overloading the main house fuse (normally 80a i think) aren't that low.
) and then try and run a 'dumb' 32a commando to a car, it's going to be providing full current for a good while if your EV battery is low, so the chances of overloading the main house fuse (normally 80a i think) aren't that low.tamore said:
i think load balancing is the big consideration. depends how your house is powered. if you run electric showers and cooking (and roof hemp farm ) and then try and run a 'dumb' 32a commando to a car, it's going to be providing full current for a good while if your EV battery is low, so the chances of overloading the main house fuse (normally 80a i think) aren't that low.
It doesn't really work like that... ) and then try and run a 'dumb' 32a commando to a car, it's going to be providing full current for a good while if your EV battery is low, so the chances of overloading the main house fuse (normally 80a i think) aren't that low.Load balancing is usually when refering to balancing load across phases.
I think what you are refering to is effectively demand management.
A 'proper' EVSE requires EXACTLY the same install as one connected by a 32A socket.
The 32A socket is no more dumb that the hardwired supply to the EVSE.
It is possible that a 'proper' EVSE can have a sense coil around the tails and vary the charge current depending on total system load.
It is theroretically possible for an 32A socket version to behave the same way (would need remote sensing). The question then becomes does any portable chager actually implement this.
Diversity calculations can be done to work out if this is a real problem or not.
If we assume that most EV charging is done overnight, then it will work out fine.
If however, you come in from work, plug the EV in and set it to charge, bang the oven on, put your tea in and jump in the shower - there very well could be a problem....
32A for EV, 13A for the oven. 40A for the shower... 85A might well pull a 80A main (probably wouldn't as it happens).
Getting the DNO to upgrade the supply to 100A, then it is all fine anyway.
(Ours is 100A)
I looked at this in quite a lot of detail... I decided 32A outlet isn't the way to go for us... but it may well be for others.
sorry, wrong terminology. load management, that's the one.
forgot i was on PH for a minute. pedantry matters
and...... it's more about when we all have to have a heat pump, electric hot water system, etc. even 100a could be short of 'plenty' and would need load management.
furthermore, catering for the lowest common denominator, not people who take an interest to understand how things work.
forgot i was on PH for a minute. pedantry matters
and...... it's more about when we all have to have a heat pump, electric hot water system, etc. even 100a could be short of 'plenty' and would need load management.
furthermore, catering for the lowest common denominator, not people who take an interest to understand how things work.
Edited by tamore on Saturday 13th August 18:25
Edited by tamore on Saturday 13th August 18:30
tamore said:
sorry, wrong terminology. load management, that's the one.
forgot i was on PH for a minute. pedantry matters
and...... it's more about when we all have to have a heat pump, electric hot water system, etc. even 100a could be short of 'plenty' and would need load management.
furthermore, catering for the lowest common denominator, not people who take an interest to understand how things work.
Appologies - didn't mean to come across as an arse!forgot i was on PH for a minute. pedantry matters
and...... it's more about when we all have to have a heat pump, electric hot water system, etc. even 100a could be short of 'plenty' and would need load management.
furthermore, catering for the lowest common denominator, not people who take an interest to understand how things work.
You are of course right. It depends where the limiting factor comes - as you say it may well be a 100A supply (23kW).
Our DNO is now putting 100A 3-ph as standard... so it looks like they are planning for bigger loads per property in the future.
Also, I have some interest in this, so not a normal 'consumer' as such.
EVs could be a big problem in the future. If charging even at relatively low rates 7kW or 22kW and you want to complete in a time window of cheaper rate, it is still going to co-incide with other high loads (you mentioned heat pumps).
It is all do-able but needs some decent consumer side management that the average consumer won't be able to do unless it is provided for them.
(Eg. drop the EV charging when heat pump or refrigeration kicks in).
Trouble is, as soon as turning off EV charging (load management) gets mentioned, everyone kicks off and whinges about it.
As it happens, I don't see a future filled with 7kW EVSE - it will go to DC chargers and V2G.
I think this has been discussed a few times. If you are going to charge a car from it then it needs to meet regs for car charging if a proper person installs it. This includes DNO notification and all sorts.
A 32A commando socket in itself will do the job though, I’m considering doing one and just swapping it back to an external 13A when we move out.
A 32A commando socket in itself will do the job though, I’m considering doing one and just swapping it back to an external 13A when we move out.
No ideas for a name said:
Our DNO is now putting 100A 3-ph as standard... so it looks like they are planning for bigger loads per property in the future.
Is that new build residential? Presumably for heat pumps? How on earth the grid will cope with loads like that, even with clever comms and timing I have no idea…andy43 said:
Is that new build residential? Presumably for heat pumps? How on earth the grid will cope with loads like that, even with clever comms and timing I have no idea…
Yes, new supplies for residential new build, and upgrades for existing.We are due 3-phase when they come to unloop our supply.
(WPD area).
It isn't just increasing demand per property that I see as the big problem. Around here there is massive development going on with hundereds of new builds. I assume each estate will get its own sub, but will need work to feed those subs.
No ideas for a name said:
Yes, new supplies for residential new build, and upgrades for existing.
We are due 3-phase when they come to unloop our supply.
(WPD area).
It isn't just increasing demand per property that I see as the big problem. Around here there is massive development going on with hundereds of new builds. I assume each estate will get its own sub, but will need work to feed those subs.
I know we're wandering off topic but at the moment EV charging (in England at least) isn't factored into the load calcs for new developments. So not only is it the HV to the subs that will need future work, but it's the sizing of the subs themselves.We are due 3-phase when they come to unloop our supply.
(WPD area).
It isn't just increasing demand per property that I see as the big problem. Around here there is massive development going on with hundereds of new builds. I assume each estate will get its own sub, but will need work to feed those subs.
ben5575 said:
No ideas for a name said:
Yes, new supplies for residential new build, and upgrades for existing.
We are due 3-phase when they come to unloop our supply.
(WPD area).
It isn't just increasing demand per property that I see as the big problem. Around here there is massive development going on with hundereds of new builds. I assume each estate will get its own sub, but will need work to feed those subs.
I know we're wandering off topic but at the moment EV charging (in England at least) isn't factored into the load calcs for new developments. So not only is it the HV to the subs that will need future work, but it's the sizing of the subs themselves.We are due 3-phase when they come to unloop our supply.
(WPD area).
It isn't just increasing demand per property that I see as the big problem. Around here there is massive development going on with hundereds of new builds. I assume each estate will get its own sub, but will need work to feed those subs.
So it's a problem and a new problem, but it's a problem that only presents itself as fast as the current business of carting around liquid fuel starts to subside. Although if you happen to be an owner of a fuel refinery to supply point logistics company, now is a good time to start considering an exit strategy. The growth of EV sales is already way ahead of predictions and that's with the growth being pegged back by supply issues. It won't be that long before local petrol stations start to suffer the same fate as local post offices in many areas.
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