UK EV Charger Earth Rod

[Ben Murray]

I have completed the 2919 course and was told during this that all chargers would require a TT connection, whether solely for the charger or as part of the full installation. Since completing the course a while ago now, I have discussed with some electricians who say they don't install an earth rod when the property is TN-C-S. What is the general view on this?
Also, the instructions for a Tesla charger says it is constantly monitoring for earth faults and over current, switching the charger off and on accordingly, does this mitigate the requirement for an earth rod? Because it is looking out for a lost neutral with a PME system? My argument is the charger could get confused thinking a main bonding conductor was the new supply to earth but we wouldn't deem this OK.

I will always install to what I believe is correct within the BS and the course I completed, but it gets confusing when you hear differing opinions within the trade. I look forward to hearing your views and welcome any suggested previous posts.

I hope everyone coping as well as they can be during the Covid-19 out break and my thoughts are with those who have lost loved ones and those who are struggling financially. Stay safe.

 

[davesparks]

I'd be asking for my money back if the course hasn't actually taught you these things!

 

[Ben Murray]

I'd be asking for my money back if the course hasn't actually taught you these things!

Thank you Dave, but not really helpful. I can only go by what I believe to be the correct information, which is, if you have a PME supply, the charger requires an earth rod.

 

[davesparks]

Thank you Dave, but not really helpful. I can only go by what I believe to be the correct information, which is, if you have a PME supply, the charger requires an earth rod.

Actually you don't have to trust to your beliefs, you can read the requirements in black and white in BS7671:2018 and the first ammendment to BS7671:2018
I don't have a copy of the first ammendment as it only relates to EV chargers and I don't install them so I can't really comment on it, however as an EV charger installer you obviously already have a copy of the first ammendment and have fully read and understood it.

 

[Ben Murray]

Scenario here is a charger being located outside.

 

[snowhead]

Did the course discuss specific chargers and what they may or may not contain and what the manufacturer may or may not recommend.

If not refer to post #2

 

[Ben Murray]

Did the course discuss specific chargers and what they may or may not contain and what the manufacturer may or may not recommend.

If not refer to post #2

I must admit, it was mostly aimed at Rolec chargers, which I did find a little annoying at the time.

 

[Wilko]

Hi - the scenario of a charger outside with an installation that’s PME requires some thought. And the answer can depend on the exact spec of charger to be installed and site factors. As @davesparks has mentioned there has been an update to the regs in this area and it’s available to read free of charge .

https://electrical.------.org/bs-7671/updates-to-18th-edition/

 

[Midwest]

Come on guys, you've not much else to do at the moment. This is a forum for discussion. Before you post, you might wish to read the notes in the reply box, before replying.

I'm just interested on how this ev charging thing will progress, asked myself recently;

EV charging points 2020 - ElectriciansForums.net Est.2006 | Free Electrical Advice Forum

I'm just interested in the technicalities of charging points, specifically with PME supplies, I know there's been a few threads on here, but I just wonder where we are with things currently. Someone posted this vid; View...

www.electriciansforums.net

You might find listening E5 Group Podcast

View: https://www.youtube.com/watch?v=YPqMVk0KgY4&list=PLKu40BuY2wcR5Ap6EBe8oVeSoKJ-ktRUH&index=29
[automerge]1585385291[/automerge]
Here's a quite long thread on a similar vein;

EV Charger Installation - Cabling Query? - ElectriciansForums.net Est.2006 | Free Electrical Advice Forum

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...

www.electriciansforums.net

 

[Ben Murray]

Ok, so I have thoroughly studied the Amendment again, notably 722.411.4.1 (iv) which says:
Protection against electric shock in a single-phase installation is provided by a device which electrically
disconnects the vehicle from the live conductors of the supply and from protective earth in accordance with Regulation 543.3.3.101 (ii) within 5 s in the event of the utilisation voltage at the charging point, between the line and neutral conductors, being greater than 253 V rms or less than 207 V rms. The device shall provide isolation and be selected in accordance with Table 537.4. Equivalent means of functionality could be included within the charging equipment. Closing or resetting of the device shall be possible only if the voltage between line and neutral conductors is in the range 207 to 253 V rms.

Which I read as basically certain chargers are designed to do this.

I cannot find any details within the Tesla manufacturers install guide stating their charger conforms to BS7671:2018 Amendment 1 regulation 722.411.4.1 (iv)

I would be comfortable to use this as a strong argument for the provision of an earth electrode still (I can only comment on a Tesla charger currently because I dont have every other charger in front of me).

 

[Midwest]

Here’s another piece on the subject, from a manufacturer who claims their device complies with 722.411.4.1 (iv) (from SparkyNinja

View: https://www.youtube.com/watch?v=FowcjLoMDUI
)

https://matt-e.co.uk/wp-content/uploads/2019/02/matte-products-and-BS-7671-2018-Amendment-1-2020.pdf

 

[pc1966]

You could achieve protection with two RCDs in series:

• First one is the normal 2-pole RCD/RCBO that you would use to protect the AC supply to any outside sort of unit. Would protect against typical L-E faults.
• Second one feeds L, N and E through a "4-pole" RCD so in the event of CNE open and someone touching the car, the shock current is detected on the E line and it then trips isolating all wires. (L & N should always balance, here they are needed simply so they are isolated simultaneously with the earth disconnection, but L-E fault will not trip in this case)

No earth rods and risk to buried services, no worries about being on the wrong phase and not seeing enough of an out-of-range voltage to trip the likes of the Matt:e boxes.

 

[Markyd]

Have a look at the MyEnergi Zappi car charger no need for earth rod no need for rcd and moniters the current so that it wont exceed the main fuse

View: https://www.youtube.com/watch?v=DnEG8jhOHBw

 

[Lister1987]

Have a look at the MyEnergi Zappi car charger no need for earth rod no need for rcd and moniters the current so that it wont exceed the main fuse

View: https://www.youtube.com/watch?v=DnEG8jhOHBw

Was gong to mention Zappi, thing that irks me no end is that they've got current monitoring and wizardry that makes them the best - no issue with that, the bit I do take issue with is the tech either not being shared without a price tag - If I were IET et all I'd be down that patent office for the inner workings or not being openly shared with Reg bodies, he'll write them a cheque if that's what it comes to.

I get R&D ain't free but when you have a game chsnging bit of tech like this and don't share it - yet harp on about caring for the environment and EV sector - that is wrong

 

[Markyd]

Was gong to mention Zappi, thing that irks me no end is that they've got current monitoring and wizardry that makes them the best - no issue with that, the bit I do take issue with is the tech either not being shared without a price tag - If I were IET et all I'd be down that patent office for the inner workings or not being openly shared with Reg bodies, he'll write them a cheque if that's what it comes to.

I get R&D ain't free but when you have a game chsnging bit of tech like this and don't share it - yet harp on about caring for the environment and EV sector - that is wrong

Totally agree.....does seem a bit naughty.because it will make the other chargers redundant