EV Charger Installation - Cabling Query?

[hyeung]

Hi,

We had a EV charger installed recently over the past day ie 32amp 7.2kw. In the fuse cupboard I’ve attached before and after photos.
I have a 100amp fuse for the house.

For the new EV board setup, should the 2 grey cables entering the EV board (10mm) be the same 25mm thickness as the other cables?

Would this cause any issues for me? Or is this against certain electrical standards?
Someone mentioned to me if I was to change the meter or DNO were to action any new improvements, that I’d have to get these 10mm cables changed before any work would be carried out in the future?

I have yet to settle on the work, so if there’s non standard work complete here due to this, I would be in a position to highlight and query the relevant electrical company. I would appreciate any advise?

Please excuse, as my knowledge in electrical stuff is non existent. It maybe that all is looks fine, and I’ve been given wrong advise.

Regards,
HY

 

[bill01803]

The tails are ok.
Have you got an earth electrode outside connected to the charging point?

 

[hyeung]

The tails are ok.
Have you got an earth electrode outside connected to the charging point?

No I don’t believe there’s any earth electrode outside as the charge point is hosted internal inside our garage, where the garage is part of the house. I assume earth electrode is not applicable as my unit is installed internally?

I assume when you refer to the tails being ok, are referring to those 10mm cables going into the new EV board?

If all looks fine, and above board. I do wonder about the previous advise given in regards to having all cables set at 25mm to avoid future problems in meter changes or any dno type work?

Thanks,
HY

 

[bill01803]

There is no requirement for 25mm tails.
If the charging point could be used to charge a vehicle outside regulation 722.411.4.1 states that PME earthing facility must not be used, ie you must have an electrode

 

[DT1991]

In this instance it would look like the garage door is very close to the charge point, so you would be able to plug in and move the car outside.

 

[DT1991]

There is no requirement for 25mm tails.
If the charging point could be used to charge a vehicle outside regulation 722.411.4.1 states that PME earthing facility must not be used, ie you must have an electrode

You can use PME and the easiest way to do this is to use a charging unit that is made for use with PME.

The 2 other ways are either near enough impossible to satisfy or get very expensive.

 

[hyeung]

There is no requirement for 25mm tails.
If the charging point could be used to charge a vehicle outside regulation 722.411.4.1 states that PME earthing facility must not be used, ie you must have an electrode

Thanks for your feedback.

Is there any truth in regards to if DNO were to action future works (upgrades) or change of meter (ie smart meter upgrade) that these 10mm tails would cause any probs? Ie DNO or provider refuse to carry out works due to these tails as a result of the recent EV charger install?

Thanks

 

[JK-Electrical]

Judging from the photos you have posted, I can't see anything wrong with this install. Tails are fine, correct type of RCD.

Did the electrician give you an Electrical Installation Certificate in respect of the work? If so, what type of earthing system has the electrician listed on the certificate in respect of the charger? TN-C-S or TT? Could you post a close-up photo of the charger?

Was the install carried-out through the OLEV Homecharge Scheme?

 

[JK-Electrical]

Is there any truth in regards to if DNO were to action future works (upgrades) or change of meter (ie smart meter upgrade) that these 10mm tails would cause any probs?

None whatsoever.

Ie DNO or provider refuse to carry out works due to these tails as a result of the recent EV charger install?

The DNO should already know about this install as electrical contractors are obliged to inform the DNO whenever EV chargers have been added to an existing installation. Sometimes notification needs to be given in advance of the install.

 

[richy3333]

The tails are ok.

Which Reg is that then in 7671?

 

[Wilko]

Hi - 10mm is more than sufficient for the load, but I would not have used it. I would use 16mm minimum into a 100A fuse to ensure disconnection without heat damage in a fault, just saying.

 

[davesparks]

Hi - 10mm is more than sufficient for the load, but I would not have used it. I would use 16mm minimum into a 100A fuse to ensure disconnection without heat damage in a fault, just saying.

Are you sure 10mm won't be adequately protected under fault conditions?

 

[Wilko]

Are you sure 10mm won't be adequately protected under fault conditions?

Oops, foot in mouth time, I’ll have to check -

100A fuse needs 580A to clear in 5 sec and plugging that into adiabatic (from Reg 543.1.3) I get minimum size as 11mm. This would be unlikely to occur as it’d need Cmin and Ze max etc.

More likely could be 850A and 1 sec and that’s about 8mm, so all good.

 

[westward10]

Who thinks there is fire proof fixings within that trunking

 

[Zdb]

I personally would have used 16mm L,N &E but as long as it's been calculated and it complies then it's all good.

 

[JK-Electrical]

Who thinks there is fire proof fixings within that trunking

Now that you've mentioned it, I'm sure the OP will be opening the trunking lid to see.

 

[pirate]

But for your suggestion, JK, I doubt he would have done so.
(Did you see what I did there? LOL!)


(Goes off to get a life...)

 

[hyeung]

Judging from the photos you have posted, I can't see anything wrong with this install. Tails are fine, correct type of RCD.

Did the electrician give you an Electrical Installation Certificate in respect of the work? If so, what type of earthing system has the electrician listed on the certificate in respect of the charger? TN-C-S or TT? Could you post a close-up photo of the charger?

Was the install carried-out through the OLEV Homecharge Scheme?

Yes certificate details see attached.
Looks like its TN-C-S; Charger is EO Mini Pro.
Assuming from the certificate that the work conforms to Reg BS7671?
Apologies due to my lack of electrical knowledge, the last few posts regarding suitability of 10mm cabling didn't mean much?
But I assume the conclusion is that the 10mm cabling used (feeding the new ev board) is all good?

It's just that some "others" have specifically mentioned that tails need to be rated at 100AMP i.e. 25mm cabling; this was my initial concern?
So hence, I just wanted to clarify this?

Yes also, the charger unit has been installed next to the garage door, so yes I could still potentially charge the car outside with the cabling routed outside. But will mainly only charge inside tbh, which is why I have it installed inside the garage.

Regarding earth protection; the EO Mini Pro unit has a some DC Leakage Protection feature built-in; hence, am I right to assume its got earth protection in some ways?
i.e.
"Earth Leakage Protection
A dedicated 30mA Type A RCD must be used on the supply circuit Integral 6mA DC leakage detection – no Type B RCD required"

 

[westward10]

If that is 6mm T&E he has the cpc size wrong on that schedule.

 

[DT1991]

If he put the R1+R2 maybe we could calculate it

 

[HappyHippyDad]

Hi,

We had a EV charger installed recently over the past day ie 32amp 7.2kw. In the fuse cupboard I’ve attached before and after photos.
I have a 100amp fuse for the house.

For the new EV board setup, should the 2 grey cables entering the EV board (10mm) be the same 25mm thickness as the other cables?

Would this cause any issues for me? Or is this against certain electrical standards?
Someone mentioned to me if I was to change the meter or DNO were to action any new improvements, that I’d have to get these 10mm cables changed before any work would be carried out in the future?

I have yet to settle on the work, so if there’s non standard work complete here due to this, I would be in a position to highlight and query the relevant electrical company. I would appreciate any advise?

Please excuse, as my knowledge in electrical stuff is non existent. It maybe that all is looks fine, and I’ve been given wrong advise.

Regards,
HY

View attachment 51231

View attachment 51232

As the others have said the 10mm tails are absolutely fine. They meet the existing regulations as the maximum demand they can ever be expected to need is 32A. They also meet the requirements for fault protection.

I realise you have mentioned a number of times that 'someone' has told you they need to be 25mm but they do not. They would need to be 25mm if they were supplying your main consumer unit (even then they may not need to be).

I would be more concerned with whether an earth rod has been installed for this install. The EO website makes no mention that their unit can be used with the earthing supply you have (i.e PME) and therefore you should have had an earth rod installed. In fact the following link by EO states clearly you should have an earth rod installed for use with their unit.

Help Center Closed - Zendesk

eocharging.zendesk.com

lastly, it's easy for us to make mistakes as we are not there. I would ask the electrician who installed it if he has installed an earth rod and if not then why? He would hopefully quote one of the 3 exceptions from BS7671 722.411.4.1 but I think this is unlikely.

 

[hyeung]

As the others have said the 10mm tails are absolutely fine. They meet the existing regulations as the maximum demand they can ever be expected to need is 32A. They also meet the requirements for fault protection.

I realise you have mentioned a number of times that 'someone' has told you they need to be 25mm but they do not. They would need to be 25mm if they were supplying your main consumer unit (even then they may not need to be).

I would be more concerned with whether an earth rod has been installed for this install. The EO website makes no mention that their unit can be used with the earthing supply you have (i.e PME) and therefore you should have had an earth rod installed. In fact the following link by EO states clearly you should have an earth rod installed for use with their unit.

lastly, it's easy for us to make mistakes as we are not there. I would ask the electrician who installed it if he has installed an earth rod and if not then why? He would hopefully quote one of the 3 exceptions from BS7671 722.411.4.1 but I think this is unlikely.

I'm pretty certain there is no external earth rod installed for this.
As the unit has been installed for use internally; is this perhaps the reason why no earth rod was installed or required?

 

[davesparks]

It's just that some "others" have specifically mentioned that tails need to be rated at 100AMP i.e. 25mm cabling; this was my initial concern?
So hence, I just wanted to clarify this?

Yes, lots of people get their regulations knowledge this way, by listening to 'others' who loudly proclaim their version or (mis) understanding of the rules as the truth.

There is a guide to the regulations which has a picture of a 'typical' domestic supply with 25mm tails feeding a single consumer unit which then supplies the whole installation. Many people fail to understand that this is just an example of a typical installation.

 

[hyeung]

Yes, lots of people get their regulations knowledge this way, by listening to 'others' who loudly proclaim their version or (mis) understanding of the rules as the truth.

There is a guide to the regulations which has a picture of a 'typical' domestic supply with 25mm tails feeding a single consumer unit which then supplies the whole installation. Many people fail to understand that this is just an example of a typical installation.

This was one of the main reasons why I posted on here, as i'd be more confident in getting the truth than from others without an electrical background....and only knowing some knowledge which is rather dangerous. As I didn't know any better, thought this would be the best course of action.

However, it is interesting that a point was raised on the appropriate earthing? If my install was used outside, then I would no doubt want to ensure that a separate earthing rod was installed. As it is used internally, are we saying that we still need an earthing rod? or is that where the exception occurs which is why the installer did not quote or require this?

 

[Deleted account]

I'm pretty certain there is no external earth rod installed for this.
As the unit has been installed for use internally; is this perhaps the reason why no earth rod was installed or required?

Is it possible to charge the vehicle when it is parked outside? Will the charge lead reach? If so it must be TT

Or does the vehicle have to be parked fully in the garage for the lead to reach? If so pme is fine.

 

[hyeung]

Is it possible to charge the vehicle when it is parked outside? Will the charge lead reach? If so it must be TT

Or does the vehicle have to be parked fully in the garage for the lead to reach? If so pme is fine.

Firstly, when I requested the install I obviously didnt know of these requirements on earthing etc.
I asked the installer that I wanted the charging unit internally within the garage and also stated on the given location of the unit. The unit sits next to the garage door from the inside.
When i use the charger i've always planned to use this internally - so car is fully parked inside.

However, to answer your question. It would be technically possible to charge the car outside provided that the car is reversed into the driveway and the garage door remains open.
I don't know if it would be possible to close the garage door and have the cabling routed outside to charge - as this might cause damage of the cabling?

Note that I don't actually have my car delivered yet, so I cant even charge it at this stage.

 

[Deleted account]

The whole instal looks to be to a very good standard. I think the installer has done well and despite my previous post I wouldn’t be too concerned.

I did the EV charge course and the one thing that seemed contradictory was the placement internally of a charge point. If it’s parked inside on a pme the charge point should be pme if it’s parked outside it should be TT.

What happens if it’s both as yours is?
In theory changing the whole of the installation to TT which is way over the top. I don’t like that solution at all.

For this reason and other points I won’t go into I don’t install these units until a better safety system has been designed and built into the units.

 

[DT1991]

Pete the whole install doesn't require TTing just the charging point in this instance.

 

[hyeung]

The whole instal looks to be to a very good standard. I think the installer has done well and despite my previous post I wouldn’t be too concerned.

I did the EV charge course and the one thing that seemed contradictory was the placement internally of a charge point. If it’s parked inside on a pme the charge point should be pme if it’s parked outside it should be TT.

What happens if it’s both as yours is?
In theory changing the whole of the installation to TT which is way over the top. I don’t like that solution at all.

For this reason and other points I won’t go into I don’t install these units until a better safety system has been designed and built into the units.

To be fair with the installer, it was me that stated that location. As the car charge port is located on the rear left side of the car. So naturally the best place was to have the charger where I've stated. As my car will be parked inside all of the time, this was the deciding factor of having the unit inside the garage.
But at the sametime, i thought the location I've picked gives me some flexibility if I wanted to use this to charge the car outside. However, at the time I was not aware of the earthing requirements until now. So unlikely to use it outside and remain to charge indoors.

Is there a large cost to install an earthing rod for this application?
Also, curiously what are the risks if the unit is using PME and one was to charge outside?

Thanks

 

[davesparks]

Pete the whole install doesn't require TTing just the charging point in this instance.

But the charge point is inside, so it can't be connected to a different earthing system as the rest of the installation inside. You cannot mix two different earthing systems within one installation like this.

 

[HappyHippyDad]

I'm pretty certain there is no external earth rod installed for this.
As the unit has been installed for use internally; is this perhaps the reason why no earth rod was installed or required?

This is a good point. Section 722 only says PME earthing shall not be used if the charge point is located externally OR if it is located internally and is used to charge a vehicle located outdoors.
If you only ever intend to charge the car in the garage then I guess this is ok.
I’d be interested in others thoughts on this?

 

[westward10]

I agree it's location is a bone of contention but then again wherever it's location like any other socket on a ground floor level it could be used out of doors.

 

[hyeung]

This is a good point. Section 722 only says PME earthing shall not be used if the charge point is located externally OR if it is located internally and is used to charge a vehicle located outdoors.
If you only ever intend to charge the car in the garage then I guess this is ok.
I’d be interested in others thoughts on this?

Would like to know too now! Does it still mean charging the car outside from the inside unit is still a no-no?

Again, what are the risks in doing so?

 

[hyeung]

I agree it's location is a bone of contention but then again wherever it's location like any other socket on a ground floor level it could be used out of doors.

I do this all the time, for the lawnmower....as I don't have an external socket - use an internal socket connected to an extension reel.

 

[HappyHippyDad]

Would like to know too now! Does it still mean charging the car outside from the inside unit is still a no-no?

Again, what are the risks in doing so?

It does mean charging the vehicle outside is a 'no no'. I 'think' it also means the vehicle should not even be capable of being charged outside if PME is used.
Here is an article that you will find interesting and it explains the risks associated with using PME earthing.

 

[telectrix]

if the prohibition of PME for EV chargers is to eliminate risk if the supply N is lost (as with metalclad caravans) the I can't see any reason to differentiate between inside or outside. a fault occuring would have a similar result, in or out. then, i have not done any research on EV so my knowledge is limited.

 

[davesparks]

This is a good point. Section 722 only says PME earthing shall not be used if the charge point is located externally OR if it is located internally and is used to charge a vehicle located outdoors.
If you only ever intend to charge the car in the garage then I guess this is ok.
I’d be interested in others thoughts on this?

I've never looked in any detail at the EV chargers regulations as ive never needed to yet. My thoughts are only based on my logic and what i've seen on the forum.

I assume the desire to connect the chargers to a TT earthing system relates to the car being connected to the installation earth whilst charging and thus becoming live during a PEN failure when connected to PME.
So if the car is inside then it becomes a big piece of exposed earthed metal whilst charging, so if it was connected to a TT system whilst the rest of the installation is connected to PME then the car would be an extraneous part to the installation introducing a dangerous earth potential.

 

[Zdb]

As long as the installer made you aware that the car must only be charged inside then it's all good. Maybe a sticker stating this on the charger itself as a reminder would have been a good idea too.

 

[DT1991]

But the charge point is inside, so it can't be connected to a different earthing system as the rest of the installation inside. You cannot mix two different earthing systems within one installation like this.

Ok so the whole installation would have to be TT for this particular set up to comply?

 

[hyeung]

As long as the installer made you aware that the car must only be charged inside then it's all good. Maybe a sticker stating this on the charger itself as a reminder would have been a good idea too.

Actually, when the installation team of 2 were out here. I did query about the cabling size to see if there was any possibility in charging the car outside, with the garaged closed (concerned that the cabling would not accommodate?). Installer didn't say or point out this concern; instead is was actually suggesting that my cabling could potentially fit through the side gap in the garage to allow outside charging! So makes you wonder eh?

 

[telectrix]

i fail to see any detriment in a PME system having a rod added as well. it's done as standard in some other countries, and round here a lot of older
TN-S systems also have a rod.

 

[hyeung]

i fail to see any detriment in a PME system having a rod added as well. it's done as standard in some other countries, and round here a lot of older
TN-S systems also have a rod.

So I assume the rod is installed outside, under the ground? I assume simply a connection from this rod is routed and connected to the charging unit inside (replacing the earth of this unit from the PME). Is that right?

 

[pirate]

My neighbour has an electric car. he parks it in the runway in front of his garage, and he brings the charging cable under the door from the garage and plugs it in to his car. There is no way he can ever get his car into the garage. Should I assume that he has an earth rod externally, because there is no evidence of such a thing. The outside parking court is a communal area, so if he has an earth rod, he needs consent from the other owners...not that anyone is likely to object, but you know how it is with awkward neighbours. Does the very fact that he parks outside, within 10' of the socket, make a difference?

 

[JK-Electrical]

I've recently quoted for two jobs and in both instances none of the other people who quoted mentioned anything to the client about the possibility of an earth rod(s) having to be installed. I asked each client for details of the EV charging unit that was to be installed. All of the units listed would most certainly have required a rod(s). The earthing system for each of the two installations was T-N-CS.

So, either the clients weren't, for whatever reason(s), informed of the need for an earth rod(s), or the installers weren't planning on fitting any. I would be most alarmed indeed if it was the latter and hope that this isn't an ominous warning of corners being cut in order to produce competitive quotes that will win jobs. Alas, I fear it is, and that yet another race to the bottom has begun within the domestic market.

Those of us who are OLEV approved installers can obtain grants on behalf of clients under the Homecharge Scheme. The grant will cover up to 75% of the installation costs of an EV charger up to a maximum of £500. As this places non-approved installers at a huge disadvantage when competing for jobs, such installers must either reduce their profit margins in order to compete. One way to do so is to cut corners. The other would be to do the City & Guilds course at a cost £400+ and then join either SELECT or NICEIC as OLEV will not approve Scottish contractors who are not a member of either of these two trade bodies.

If an EV charger is to be installed on a T-N-CS system, not only is a rod(s) to be installed, but additional measures also need to be taken. For instance, any class I luminaires that are connected to the T-N-CS system and are located within simultaneous touching distance of the charger, the connection point and the vehicle under charge; would need to be replaced with class II fittings. Any extraneous conductive metalwork such a water or gas pipe would either need to be shielded in a non-conductive enclosure or converted to plastic piping. These arrangements are absolutely vital so to prevent simultaneous contact being made by a person between two different types of earthing systems. A risk-assessment needs to be undertaken. The written risk assessment document should be appended to the Electrical Installation Certificate. For clarity and reference, I have uploaded section 6.8 of the Code of Practice for Electric Vehicle Charging Equipment.

On the basis of what I have seen in the photographs that were uploaded by the OP, I conclude that an earth rod(s) should have been installed. Furthermore, there is no mention in the manufacturer's installation instructions for the EO Mini Pro that their product incorporates any in-built protection that would negate the need for an earth rod(s).

Although the OP has conceded in a previous post that it was him/her who advised the contractor to install the charger in the position that it now occupies, the contractor should nevertheless have been aware of the risks that would ensue from positioning the charging point in a place where it could be used to charge a vehicle located outdoors and should have advised the OP accordingly IMHO.

 

[HappyHippyDad]

So I assume the rod is installed outside, under the ground? I assume simply a connection from this rod is routed and connected to the charging unit inside (replacing the earth of this unit from the PME). Is that right?

Its probably best to put all these points to the electrician who installed it, they can then hopefully answer some of the questions.
If a rod does need to be installed it then needs to be connected at the right point in the installation (I.e. the small consumer unit housing the RCD and circuit breaker). The earth cable going into the small consumer unit would need to be removed otherwise you have 2 separate earthing systems together.
The earth cable needs to be the correct size and the earth rod needs obtain a suitable resistance value.
But... rather than getting bogged down with lots of differing views on this forum I would chat to the installing electrician. They seem to have done a neat job and have ticked all other required boxes (apart from one or 2 errors in the certificate), so put the questions to them now that you have a little more knowledge.

 

[JK-Electrical]

I've never looked in any detail at the EV chargers regulations as ive never needed to yet. My thoughts are only based on my logic and what i've seen on the forum.

I assume the desire to connect the chargers to a TT earthing system relates to the car being connected to the installation earth whilst charging and thus becoming live during a PEN failure when connected to PME.
So if the car is inside then it becomes a big piece of exposed earthed metal whilst charging, so if it was connected to a TT system whilst the rest of the installation is connected to PME then the car would be an extraneous part to the installation introducing a dangerous earth potential.

Spot on Dave.

 

[JK-Electrical]

If a rod does need to be installed it then needs to be connected at the right point in the installation (I.e. the small consumer unit housing the RCD and circuit breaker). The earth cable going into the small consumer unit would need to be removed otherwise you have 2 separate earthing systems

No! The rod is connected to the EV charger!! The CPC of the T&E would be insulated and parked at the charger end of the circuit, but connected to the MET at the supply side of the circuit. It's no different from the arrangement that would be used if you were installing a consumer unit in a garage via a TT system.

 

[JK-Electrical]

So I assume the rod is installed outside, under the ground? I assume simply a connection from this rod is routed and connected to the charging unit inside (replacing the earth of this unit from the PME). Is that right

Correct!

 

[JK-Electrical]

Ok so the whole installation would have to be TT for this particular set up to comply?

No. The whole installation remains T-N-CS apart from the EV charging circuit. As the rod is connected to the EV charger only that one dedicated circuit becomes TT.

 

[JK-Electrical]

https://professional-electrician.com/features/are-you-installing-earth-electrodes-correctly-for-electric-vehicle-charging-points