HappyHippyDad

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Evening all.

I have been asked to quote for an electric car charging point. The customer has specifically asked for a 32A commando socket to be fitted.

I have not fitted a home charging point before and was hoping to hear how some of you guys had done it as reading literature on it there seems to be varying ideas.

I have not been to see the customer yet although I 'think' his present earthing system is a TT as I have been there before. If I am wrong and it is PME am I right in thinking that the charge point would need its own seperate TT (if the charge point is outside)? This is what is mentioned in a copy of Wiring matters.

I would put it on its own dedicated circuit on a 32A type B MCB and if no RCD protection would provide it.

Cheers.

Ps.. I will get around to changing my avatar back!!! But at present GLENN I cannot find the previous picture that I used, i'll get you back one day :13:
 
Evening all.

I have been asked to quote for an electric car charging point. The customer has specifically asked for a 32A commando socket to be fitted.

I have not fitted a home charging point before and was hoping to hear how some of you guys had done it as reading literature on it there seems to be varying ideas.

I have not been to see the customer yet although I 'think' his present earthing system is a TT as I have been there before. If I am wrong and it is PME am I right in thinking that the charge point would need its own seperate TT (if the charge point is outside)? This is what is mentioned in a copy of Wiring matters.

I would put it on its own dedicated circuit on a 32A type B MCB and if no RCD protection would provide it.

Cheers.

Ps.. I will get around to changing my avatar back!!! But at present GLENN I cannot find the previous picture that I used, i'll get you back one day :13:

have a look at 722.411.4.1 and the whole of section 722 is worth a read. page 279 BYB
 
Are you installing a charger or just a socket to feed a charger?
The RCD requirement is a different type to the usual RCD so even if there is already RCD protection you'll probably need to provide additional protection
 
Are you installing a charger or just a socket to feed a charger?
The RCD requirement is a different type to the usual RCD so even if there is already RCD protection you'll probably need to provide additional protection

yes 722.531.2.101
 
I thought the requirement to TT, only applied to street furniture, not home charging?
 
I would highly recommend the Rolex chargers, very good, they have a built in RCD too. Nice bit of kit.

when you quote or buy one, find out what car is going on it as you will need to know which type it is, Tyoe 1 or Type 2, it depends if it's Japanese or European.

HHD, I've fitted a few and know what im doing with them.
 
I thought the requirement to TT, only applied to street furniture, not home charging?

one way of complying with a TN system is to connect a rod to the MET so the rms voltage between the MET and Earth does not exceed 70V.
 
Are you installing a charger or just a socket to feed a charger?
The RCD requirement is a different type to the usual RCD so even if there is already RCD protection you'll probably need to provide additional protection

My title should have been accurate. The client has specifically asked for the commando socket so I'm assuming he must have the charger that's intended to be used.
 
Then that will tell you which type of install it is when you look at the appropriate section in the regs.
From there you can read the requirements for your install
 
I would highly recommend the Rolex chargers, very good, they have a built in RCD too. Nice bit of kit.

when you quote or buy one, find out what car is going on it as you will need to know which type it is, Tyoe 1 or Type 2, it depends if it's Japanese or European.

HHD, I've fitted a few and know what im doing with them.

I've read a little about the different types of charging systems however this chap is just asking for the 32a commando socket. Do you always fit the charger UK or have you sometimes just been asked for the electric point as the car has an on-board charger as Dave mentioned?
 
This may be for an 'on board' charging system perhaps ?

I'm guessing it must be Dave. The client is very articulate and knows what he wants but I'd like some more info.
 
I have always fitted a charger with the correct outlet for a car, I'm not aware of an option that would allow you to connect a car to a 32A commando socket, it doesn't seem right.

all EV cars as far as I am aware have a type 1 or type 2 inlet and you need a suitable lead, and non or them go to a commando socket, I would 100% clarify exactly what it is is being plugged in.
 
Just to add, if it was just on a normal commando socket, it would allow you to just pull it out without turning it off which is why you use the correct lead
 
I believe the Gwiz cars use a commando lead and plug.
Not sure, but I think it's 16A?
 
Are you installing a charger or just a socket to feed a charger?
The RCD requirement is a different type to the usual RCD so even if there is already RCD protection you'll probably need to provide additional protection

yes 722.531.2.101

That could be interesting to accomplish if the CU is a dual RCD board. 722.531.2.101 states protected 'individually' by an RCD! You could easily add another RCD to protect just that point (to meet the reg) but then theres no discrimination so it would be pointless.
 
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That could be interesting to accomplish if the CU is a dual RCD board. 722.531.2.101 states protected 'individually' by an RCD! You could easily add another RCD to protect just that point (to meet the reg) but then theres no discrimination so it would be pointless.

That is one of the problems with dual RCD boards.
You cannot add another RCD as you suggest because then it would not be protected individually, the RCD at the cu would still be shared.
You will have to come from a non-RCD way or a seperate CU.
 
I have always fitted a charger with the correct outlet for a car, I'm not aware of an option that would allow you to connect a car to a 32A commando socket, it doesn't seem right.

all EV cars as far as I am aware have a type 1 or type 2 inlet and you need a suitable lead, and non or them go to a commando socket, I would 100% clarify exactly what it is is being plugged in.

A 13A socket to bs1363 or an interlocked commando socket are permitted for AC supplies for charging.
 
Just to add, if it was just on a normal commando socket, it would allow you to just pull it out without turning it off which is why you use the correct lead

Which might be why the regulations require an interlocked socket
 
If the customer has asked you to install a 32A commando socket then that is what you do really.
If the customer then decides to plug in an electric car to that socket that is up to him, you cannot dictate what the use to which a socket may be put. To meet the charging safety requirements the charger being used should be independently adequately protected.
If the car were charging on a BS1363 socket it could also be a general use socket.
However if you do have a TT system then this does simplify the install even if you do take account of the charging point requirements it is only the type A / B RCD protection that causes hassle, but most car charging units have these fitted anyway.
Does the current guidance still have the domestic "we know what is going to happen" exclusion for TNCS systems?
 
If the customer has asked you to install a 32A commando socket then that is what you do really.
If the customer then decides to plug in an electric car to that socket that is up to him, you cannot dictate what the use to which a socket may be put. To meet the charging safety requirements the charger being used should be independently adequately protected.
If the car were charging on a BS1363 socket it could also be a general use socket.
However if you do have a TT system then this does simplify the install even if you do take account of the charging point requirements it is only the type A / B RCD protection that causes hassle, but most car charging units have these fitted anyway.
Does the current guidance still have the domestic "we know what is going to happen" exclusion for TNCS systems?

Do you mean with regards PME and earthing for electric cars Richard?
 
Yes 722.411.4.1 I believe is still current so practicality can take over if the supply is TNCS (PME).
(Now that I have looked it up, I really ought to read the current regs!)
 
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Have to admit I still automatically pick up the BGB, even though the BYB is right next to it! The BGB has all my notes and scribblings in it... but it doesn't have section 722 which I am embarrassed to say I did not realise existed.

Thanks again Lee.
 
I thought there were company's going around fitting car charging points for free from some government scheme I have seen 2 houses myself who have had them fitted and don't even have a car to charge up, may be worth having a look into it
 
Yes 722.411.4.1 I believe is still current so practicality can take over if the supply is TNCS (PME).
(Now that I have looked it up, I really ought to read the current regs!)

The 'wiring matters' aricle (View attachment 2012_44_autumn_wiring_matters_Electric_vehicles_and_PME.pdf) stated that you could not use PME earth for a charging point :

"Without data, the committee was
unable to conclude that the risk of usinga PME earth was low enough to consider
a PME earthing arrangement suitable to
supply charging equipment for outdoor
connecting points."

It does go on to say :

"Subsequent to this decision, and
recognising that there are limited
options available to the installer, as well
as other risks associated with using a TT
system, IET Standards Ltd agreed to
commission a risk analysis to determine
the risk associated with using PME
supplies. The objective is to carry out a
quantitative evaluation of the increased
level of risk associated with using a PME
supply for outdoor connecting points.
IET Standards Ltd has commissioned
the Health and Safety Laboratory (HSL)
to carry out this work. The programme
started in July and is due to finish in
September. The findings of the HSL will
be published in a report, which will be
made publicly available."

I'm assuming this research has been incorporated into section 722? Does anyone know where we could find the results from this study?

ps.. sorry for varying size writing!
 
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I thought there were company's going around fitting car charging points for free from some government scheme I have seen 2 houses myself who have had them fitted and don't even have a car to charge up, may be worth having a look into it

Yes, that would be good Flanders. I'll start ringing around and hopefully, eventually find someone who will do it for free. I'll then contact the client and say 'Merry Christmas, ring this number and dont worry about paying me!"

Only kidding :smile: I'll mention it to them, but I expect they have already looked into this as he's a pretty clued up client.
 
Someone could buy this book; Code of Practice for Electric Vehicle Charging Equipment Installation 2nd Edition - The IET

and perhaps we it might help us all? I'm doing an extension at the mo, was going to suggest to the customer about running a cable in for a car charger, as a future proof thing. Don't think I'll bother :speechless:
 
Ok Only a thought I think the company's are doing it just to make money from the government, like free loft insulation etc, i would not recommend one of these company's to do the work as what i seen was a bit shoddy
 
As a matter of interest, are all car battery charge leads universal or are there differed types for differed models?
 
Found this gov doc; https://www.gov.uk/government/uploa...nce-for-manufacturers-and-installers-2015.pdf

which as uksparks says, different types of sockets, and can include grants for customer. I see that there are 3kw chargers for overnight charging, 7.2kw for 4hr charging, which looks to become the norm for the time being. There are faster chargers, 22kw +, which I think would be beyond the scope of most domestic properties, designed for topping up your spaceship when you get to work!

uksparks, did you do the course?

http://www.electriciansforums.co.uk...orum/88166-electric-vehicle-charging-pme.html
 
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It depends if it's a Japanese car or a European car, so it will either be a type 1 or type 2 connector. They look similar.

By Japanese, do you mean imports or all Jap cars in general?
 
Or take one of these courses and tell us how to do it HHD; https://www.tradeskills4u.co.uk/cou...rging-course?gclid=CKPk_ufB9MkCFda4GwodmKkGDw

From some pdf's on the subject, whilst we wait for uksparks
'Install an isolating transformer in the electric vehicle charging equipment circuit to separate the supply earthing arrangement from the equipment'.

And IET pdf; Regulation 722.411.4.1 does not allowPME as a means of earthing for an electric vehicle charging point where the charging point or the vehicle is located outdoors except where 722.411.4.1(i) or 722.411.4.1(ii) or 722.411.4.1(iii) apply. There is an exception for a dwelling if none of (i), (ii), or (iii) is reasonably practicable. It is worth noting that in this regulation the meaning of ‘dwelling’ is restricted to a self-contained unit designed to accommodate a single household. Regulation722.411.4.1(i) refers to a situation where a connecting point is supplied from a three-phase installation used to supply loads other than charging points and where the load is sufficiently well balanced. Regulation 722.411.4.1(ii) requires a very low resistance earth electrode tomitigate the effects of an open circuit PEN conductor fault on the supply. Regulation 722.411.4.1(iii) also require san earth electrode. Regulation722.411.4.1(iii) is based on the installation requirements (from the 14th edition wiring regulations) for a voltage operated earth leakage circuit breaker. However, the device differs from the BS 842 voltage operated earth leakage
circuit breaker. A product standard for a protective device for the purposes of (iii) is being developed by BSI Committee PEL/23/1.
The touch voltage threshold of 70V mentioned in 722.411.4.1(i) and 722.411.4.1(ii) and 722.411.4.1(iii) is on the basis that Table 2c (Ventricular fibrillation for alternating current 50/60Hz) of IEC 60479-5[ed1.0] gives a value of 71V for both-hands-to-feet, in water-wet conditions with medium contact area (12.5cm2).
I'll let your more eductaed bods, pick the bones out of that. Yawn, tired now. Soon be Xmas. :yawn:
 
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Without access to the new Regs, all I can say is: As far as I am aware, the prohibition on using a PME earthing point, relates to street furniture, and not to home charging points.
 
Without access to the new Regs, all I can say is: As far as I am aware, the prohibition on using a PME earthing point, relates to street furniture, and not to home charging points.

You could be right there! How would the ordinary man or woman in the street know whether it’s safe to plug their car in if these leads are readily available. They can’t possibly know what the earthing arrangements are.
Charge cable.jpg
 
You could be right there! How would the ordinary man or woman in the street know whether it’s safe to plug their car in if these leads are readily available. They can’t possibly know what the earthing arrangements are.
View attachment 31027

Thats a good point! The regs (722) actually say you can use a designated standard BS1363-2 socket. Like you said, how does the client know if they have a PME or TT??

Plus, could anyone shed light on why the installation would need its own seperate RCD? Apart from the nuisance value with an RCD that protects more than one circuit are there any other reasons why the reg would state this?
 
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HappyHippyDad

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Installation of home charging point for electric car.
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