EV Charger Installation - Cabling Query?

[bill01803]

The cert is 17th edition, when was the job done?

 

[marconi]

Dear JK-Electrical, you have made a major contribution (#44) to this thread and are clearly installing EV professionally and strictly in accordance with the regulations - thank you and 10/10 Sir.

I did not read Davesparks' comments as directed at you and intended to make you look foolish; rather I interpreted his remarks as directed at the regulations and how they will perform in practical settings - a professional debate on the regulations then, some of the content of which he regards as 'foolish'. Not a great choice of word though IMHO - perhaps ill-thought out would be better said.


M

 

[HappyHippyDad]

I obtained a copy of the report mentioned in the wiring matters magazine article (linked in post #35) sometime ago.

It was an in depth study on the use of PME with regards electric vehicle charging points, authorised by the IET standards Ltd and carried out by the Health and safety Laboratory (HSL).

I have the full report in my emails if anyone wants a copy (I seem to be unable to save/copy it) or the 'results' part of the report is below. It does seem that the 'additional' risk of using PME for the EVCP is very, very low.
From the report below you can see that the 'additional' risk of death or serious injury (p/year) is 0.0000011 (this is 1 in a million). This is also the worst case scenario AND they state that the risk value calculated is likely to be significantly higher than reality, so this means the risk is likely to be far lower than 1 in a million (for example 1 in 10 million), meaning its highly, highly unlikely to pose an additional risk of death or serious injury.

 

[HappyHippyDad]

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

Thanks alot for putting this video clip up JK, it was very interesting and answered a few questions for me.
I see where you are coming from with regards connecting the earth rod to the charge point, you are referring to method (ii) of 722.411.4.1. You are basically adding a supplementary earth electrode rather than making the whole system TT.

 

[hyeung]

Hi,

Hmm i'm not sure where to start with all this. There appears to have been a lot of debate on the subject, and some of the discussions i'm not even entirely sure if I fully followed or not?

Please correct me if I'm wrong in my understanding.

1) The primarily use of the EVCharger will to charge the car whilst it is parked inside the garage. I wanted to confirm that, for this primary purpose am I correct to say that the current installation/setup is OK? So while the car is charging in the garage and in the event of a certain major fault conditions (PEN faults?), we would not be at ANY risk whilst inside, despite touching the car or anything metal in the surroundings (see uploaded photos).
And in this setup, we would not required an earthing rod for this primary use stated here?

2) The main issue that arises is when one decides to charge the car parked outside i.e. car is on the monoblock drive outside of the garage door, whilst connected to the internal EVCharger unit. Under this scenario, if a major fault condition (PEN fault) occurred, there would be a risk if one was touching the car and standing outside on the driveway? In this use-case scenario, one would require an earth rod installation to mitigate the above risk. Is that correct?

However, in situation where I do have an earth rod installed to accommodate use-case scenario (2). Does that mean I can no longer charge the car whilst inside the garage as per use-case (1) without risk?
If I get an earth rod installation, can it accommodate both scenarios of (1) and (2)?

I am not sure I fully understood the previous debates, but seemed to get the impression that if we had an earth rod setup it'll be fine to charge the car outside (scenario 2); but this then has a knock-on-effect as could cause similar risks if one is to charge the car inside the garage and a fault condition arises (PEN fault).
Is this correct?

It sounds like for the given EVCharger that we have, I can only either use this inside only or outside only; and not a mix. Again, correct me if i'm wrong as this is what I've picked up.
At the moment due to the installation setup, i'm only safe to use this when the car is charged inside.
If that is the case, that's fine I would opt to charge the car inside. Prior to the install I was never aware of this issue, no mention was made on the earth rod etc.

I assumed that one could use it charger both ways (inside and outside - provided you could get the cable out). If I have to choose, I'm happy to stick with using the charging inside the garage as this will be my primary use.

Btw, just to be clear i have posted some further pictures of the garage surrounds as it shows other items in there i.e. boiler, any gas pipework, garage opener, smoke alarms etc. In case its of any relevance to all this...

Just to add, the installation was only carried out on Friday. The company is approved for the OLEV scheme; and I also got an application for EST funding for this install.
I wish I knew about this issue, as I may have ended up picking a different charging unit that didn't require earth rod requirements.

I really appreciate everyone's input; and your patience.

Cheers,
HY

 

[Deleted account]

I think you’ve pretty much got it.

As for choosing a unit that wouldn’t need an earth rod. They don’t exist yet.

It states in ev code of practice you can install a voltage trip monitoring device, but they don’t exist and haven’t been invented yet.

This is one of the reasons I don’t fit EV yet even though I can as I’ve done the C&G course.
It’s not been thought through.

 

[Deleted account]

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.

the below confirms my earlier statement.

 

[Deleted account]

Photo didn’t work
Ev code of practice.
6.9 (iii) if a risk assesment shows that the risk of simultaneous contact between any accessible conductive parts connected to PME earth , and any extraneous or exposed conductive parts associated with outdoor vehicle charging equipment( including the connection point and the vehicle on charge) cannot be prevented, the adoption of a TT system for the whole installation can be considered.

 

[HappyHippyDad]

Hi,

Hmm i'm not sure where to start with all this. There appears to have been a lot of debate on the subject, and some of the discussions i'm not even entirely sure if I fully followed or not?

Please correct me if I'm wrong in my understanding.

1) The primarily use of the EVCharger will to charge the car whilst it is parked inside the garage. I wanted to confirm that, for this primary purpose am I correct to say that the current installation/setup is OK? So while the car is charging in the garage and in the event of a certain major fault conditions (PEN faults?), we would not be at ANY risk whilst inside, despite touching the car or anything metal in the surroundings (see uploaded photos).
And in this setup, we would not required an earthing rod for this primary use stated here?

2) The main issue that arises is when one decides to charge the car parked outside i.e. car is on the monoblock drive outside of the garage door, whilst connected to the internal EVCharger unit. Under this scenario, if a major fault condition (PEN fault) occurred, there would be a risk if one was touching the car and standing outside on the driveway? In this use-case scenario, one would require an earth rod installation to mitigate the above risk. Is that correct?

However, in situation where I do have an earth rod installed to accommodate use-case scenario (2). Does that mean I can no longer charge the car whilst inside the garage as per use-case (1) without risk?
If I get an earth rod installation, can it accommodate both scenarios of (1) and (2)?

I am not sure I fully understood the previous debates, but seemed to get the impression that if we had an earth rod setup it'll be fine to charge the car outside (scenario 2); but this then has a knock-on-effect as could cause similar risks if one is to charge the car inside the garage and a fault condition arises (PEN fault).
Is this correct?

It sounds like for the given EVCharger that we have, I can only either use this inside only or outside only; and not a mix. Again, correct me if i'm wrong as this is what I've picked up.
At the moment due to the installation setup, i'm only safe to use this when the car is charged inside.
If that is the case, that's fine I would opt to charge the car inside. Prior to the install I was never aware of this issue, no mention was made on the earth rod etc.

I assumed that one could use it charger both ways (inside and outside - provided you could get the cable out). If I have to choose, I'm happy to stick with using the charging inside the garage as this will be my primary use.

Btw, just to be clear i have posted some further pictures of the garage surrounds as it shows other items in there i.e. boiler, any gas pipework, garage opener, smoke alarms etc. In case its of any relevance to all this...

Just to add, the installation was only carried out on Friday. The company is approved for the OLEV scheme; and I also got an application for EST funding for this install.
I wish I knew about this issue, as I may have ended up picking a different charging unit that didn't require earth rod requirements.

I really appreciate everyone's input; and your patience.

Cheers,
HY

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View attachment 51255

I'll try and answer some of your points hyeung but I think the main answer is that electric vehicle charging points (EVCP) are fairly new and as such all the implications have not been thought through, so you may not get the simple 'yes/no' answers that you would like (as I would).

Point 1
The way I read it you should not even be able to charge the vehicle outside if it is PME, just having good intentions of always doing it inside is not good enough as at some point someone will do it outside, be it your self or the next owners.
However, if you do charge it inside then the risk will be far less (its kind of impossible to say negated as there is always some risk with electrics). This is assuming that your existing electrics are up to standard, in particular you have all the required Main bonding in your house or indeed bonding in the garage if required.

Point 2
Having an earth rod for the whole garage or perhaps just for the EVCP would seem to negate the effect of electric shock whilst outside as long as you cannot come into contact with any metal parts (whilst simultaneously touching the car) which are part of the PME system, exposed or extraneous.

As with point 2 it would still be ok to charge the vehicle indoors if you have an earth rod as long as you cannot come into simultaneous contact with any metal parts which are part of the PME system. (e.g. touching car and other metal part at the same time)

I would have thought a bit of investigation when installing these units would be undertaken to establish if any extraneous conductive parts are simultaneously touchable with the vehicle or charging point.

 

[hyeung]

I'll try and answer some of your points hyeung but I think the main answer is that electric vehicle charging points (EVCP) are fairly new and as such all the implications have not been thought through, so you may not get the simple 'yes/no' answers that you would like (as I would).

Point 1
The way I read it you should not even be able to charge the vehicle outside if it is PME, just having good intentions of always doing it inside is not good enough as at some point someone will do it outside, be it your self or the next owners.
However, if you do charge it inside then the risk will be far less (its kind of impossible to say negated as there is always some risk with electrics). This is assuming that your existing electrics are up to standard, in particular you have all the required Main bonding in your house or indeed bonding in the garage if required.

Point 2
Having an earth rod for the whole garage or perhaps just for the EVCP would seem to negate the effect of electric shock whilst outside as long as you cannot come into contact with any metal parts (whilst simultaneously touching the car) which are part of the PME system, exposed or extraneous.

As with point 2 it would still be ok to charge the vehicle indoors if you have an earth rod as long as you cannot come into simultaneous contact with any metal parts which are part of the PME system. (e.g. touching car and other metal part at the same time)

I would have thought a bit of investigation when installing these units would be undertaken to establish if any extraneous conductive parts are simultaneously touchable with the vehicle or charging point.

I'll try and answer some of your points hyeung but I think the main answer is that electric vehicle charging points (EVCP) are fairly new and as such all the implications have not been thought through, so you may not get the simple 'yes/no' answers that you would like (as I would).

Point 1
The way I read it you should not even be able to charge the vehicle outside if it is PME, just having good intentions of always doing it inside is not good enough as at some point someone will do it outside, be it your self or the next owners.
However, if you do charge it inside then the risk will be far less (its kind of impossible to say negated as there is always some risk with electrics). This is assuming that your existing electrics are up to standard, in particular you have all the required Main bonding in your house or indeed bonding in the garage if required.

Point 2
Having an earth rod for the whole garage or perhaps just for the EVCP would seem to negate the effect of electric shock whilst outside as long as you cannot come into contact with any metal parts (whilst simultaneously touching the car) which are part of the PME system, exposed or extraneous.

As with point 2 it would still be ok to charge the vehicle indoors if you have an earth rod as long as you cannot come into simultaneous contact with any metal parts which are part of the PME system. (e.g. touching car and other metal part at the same time)

I would have thought a bit of investigation when installing these units would be undertaken to establish if any extraneous conductive parts are simultaneously touchable with the vehicle or charging point.

Hi,

So for point 1; sounds like I'm perfectly fine with indoor charging as it stands. I wasn't sure what you meant by bonding.

For point 2; assuming i had the earth rod setup, as per my recent uploaded photos. The only obvious metal areas that come to mind would probably be the gas pipe entering the wall towards to garage door and where that pipe comes down toward the boiler. The garage opener situated at the top; i imagine is using the house earth (PME), and not sure if that conducts with the garage door as such.

Looking at the gas pipe connection from outside coming in, it appears to be earthed.

It just sounds impratical if one has to shield all these areas? assuming I am correct on what i've highlighted?

You can give me your thoughts, but it sounds like alot hassle to accommodate this indoor charger for outdoor use; and as my primarily use is indoors, then i might as well just stick with that. I appreciate it doesn't negate things from a safety point of view as it does not stop some else using it in another way.
Not sure what to do!?
If i knew this, i would have consider a different unit that supports PME i.e. Zappi or the more expensive Andersen A2 units.

Is it still worth while querying the installer, on the use of this outdoors to see what they say? or just act unaware and mention I noticed that for the unit, there appears to be mention of a mandatory earth rod required for this given unit i.e. does this mean i can't use this outside etc?

Can I ask what the cost would be involve to get an earth rod installed? I assume the part is cheap but more of the labour? Sounds like i'm gonna get stung for additional labour costs to install? But as mentioned, if makes charging inside problematic then i'd be inclined not to do it?
Thoughts?

 

[Midwest]

I've been reading these posts & links back and forth, and I 'm confused. Easily done.

After watching the vid, I think it suggest using a supplementary earth, connected to the MET of a TN-C-S supply. Why would TT'ing just the charger be an option, with the problems outlined?

 

[HappyHippyDad]

It is all getting a bit confusing isn't it!
I know what i'd do in my own home but i'm afraid that would be irresponsible to say on a open forum!
Have a chat with the installer @hyeung and put a few of these points to them.

 

[Midwest]

I've been reading these posts & links back and forth, and I 'm confused. Easily done.

After watching the vid, I think it suggest using a supplementary earth ROD, connected to the MET of a TN-C-S supply. Why would TT'ing just the charger be an option, with the problems outlined?

Missed that bit in my post

 

[Midwest]

It is all getting a bit confusing isn't it!
I know what i'd do in my own home but i'm afraid that would be irresponsible to say on a open forum!

Go on, your secret would be safe with us.

 

[Midwest]

As for choosing a unit that wouldn’t need an earth rod. They don’t exist yet.

This suggests they do exist?

Do EV chargers need earth rods

Electric vehicle charge point manufacturers are adding intelligent electronics to remove the need for earth rods.

www.efixx.co.uk