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How do they fit charging points

nheather

Distinguished Member
My wife has ordered a Nissan Leaf which gets delivered in November.

Looking into charging points and coming down to three options, Podpoint, Rolec and Chargemaster.

The favourite at the moment is Podpoint simply because they provide the most information on their website. The other two have limited information and simply say that the installer will discuss options with us - so basically, we can’t find out what it does, what options there are, how much they will cost until we place an order.

Our installation should be pretty straight forward. We wanted it fitted on a wall - the other side (indoors) of that wall is the consumer unit. Also less than two metres around the corner on the external wall is the meter box.

Do they connect to the consumer unit or the meter box. I’d prefer them to connect to the consumer unit as it would be neater but they may push for the meter box as it would be simpler. Not that the consumer box is difficult, it is pretty easy with a short run and if the meter box wasn’t so close I don’t think they would have an issue at all, I just think with the meter box being even easier they might push for that.

Cheers,

Nigel
 

LV426

Administrator
Staff member
In my case, PodPoint installed a separate small consumer unit with a single circuit breaker, wired directly to "my" side of the meter and mounted inside the meter box, and then ran an armoured cable from that to the wall outlet (which is some considerable distance away). That would certainly have been easier than coming off my existing consumer unit, but I don't know whether either approach is standard practice or whether they just choose which is easiest.

My suspicion is that it's probably not easy getting an armoured cable in to an already "full" consumer unit. But then, if they were, in your case, going straight through a wall, armoured may not be required.
 

IronGiant

Moderator
Generally I think they will connect to your side of the meter, at the meter. Unless you have have a Henley block at the consumer unit which will be easy to tap into. A Henley block is like a giant chocolate block connector for attaching additional "meter" tails, as I found out when watching Stuart's Youtube video of his charger being fitted. e.g. 2 x 5-Way DP 100A Service Connector Block 25mm²
 

ufo550

Distinguished Member
I have no experience professionally of ev chargers, however both methods of providing a 32A supply (or similar), previously described are perfectly acceptable.

Clearly there might be limitations on spare capacity in a CU, and whether the CU has suitable RCD protection and/or whether the CU would provide division of circuits, in the event of a fault with charger etc. It might be simpler to install another small CU, feed via Henley Boxes from your incoming supply (after the meter).

The latest edition of the Wiring Regs, provides certain certain requirements for ev charger circuits, especially where the property has a pme supply: the majority of housing would be pme. Devices like the Podpoint (I believe) provide the technology to automatically disconnect the supply (including earth) to the car in the event, that the voltages vary between a certain range. Though there is some doubt by some particular 'experts' that that would be effective across all possibilities.

I think I'm right in think you have to get a particular authorised installer (with the grant etc). I would obtain a couple of quotations from different installers.
 

IronGiant

Moderator
We're having a new charger (Rolec tethered ) fitted on Monday and they are installing a separate earth for it? if I've got that right?
 

IronGiant

Moderator
The earth is currently connected to the metal sheathing the incoming mains supply runs in. I'll find out on Monday exactly what they propose.
 

noiseboy72

Distinguished Member
Fitting additional earthing points to a PME installation requires permission from the electrical supply distributor, as you are changing the supply type to TT. What will normally happen is that they will fit an earth rod that connects to the earthing terminal of the charger only, along with its own RCBO or RCD. This avoids changing the rest of the household earthing. The earth terminal on the charging point is therefore not linked to the rest of the household earths, which are connected to the neutral cable where it enters the building.

The concern with PME and electric cars is similar to that with caravans and mobile homes. You have a metal structure that is isolated from the ground by its tyres, but is connected to the house's earthing system. As the neutral and earth is combined at the incomer to the house, some fault types could cause the metal part of the car to become live. A person then touching that metal work could then become an earth path to ground. The earth rod should prevent this from happening, giving a good earth path and allowing the RCD to correctly protect the supply.
 

ufo550

Distinguished Member
The earth is currently connected to the metal sheathing the incoming mains supply runs in. I'll find out on Monday exactly what they propose.

It sounds like your supply is possibly TN-S, the earthing facility is provided by the lead sheath of the supply cable. However, as old network cables breakdown and are repaired, they are converted by the DNO to TN-C-S or PME.

You do not need permission from anyone to install an earth rod or convert to TT, unless its not your property.

Part of @noiseboy72 last paragraph is correct. There is a potential danger from using a PME out of the equipotential zone, of a premise. Reg 722.411.4 gives specific guidance on using PME for ev charging, for outdoors or could reasonably be expected to be used outdoors.

The use of an earth rod and converting the supply for the charger to TT is one of them. However the resistance of the earth rod and protective conductor or Ra has to meet a certain resistance, dependant partly on the installation current. Generally a few ohms. A typical Ra of 100ohms is considered suitable in other contexts.

I've looked on Rolec's website, to se how their devices comply with 722.411.4. Other than they use a Type A RCD's, they don't seem to say much.

I don't want to cause any concern at such short notice, just brining it to your notice.

Is the installer, when of theirs or through a third party?
 

IronGiant

Moderator
It's a Rolec appointed installer. Thanks for your input, it's interesting.
 

ufo550

Distinguished Member
It's a Rolec appointed installer. Thanks for your input, it's interesting.

Think I might start a thread, with regard to the supply circuits for ev chargers. I've been thinking that my next motor might be electric, so I've been doing some research, and its quite alarming how people & manufacturers have different ideas on this subject. Things are changing rapidly.

Perhaps made into a sticky, for this particular section & members info?

Lets us know how it goes, I would be interested on what they install. Make sure you get a copy of an Electrical Installation Certificate and that they notify to your LBC.
 

IronGiant

Moderator
Perhaps made into a sticky, for this particular section & members info?
That sounds like a good idea :thumbsup:

I'm not sure how much installation will occur as it's essentially a like for like swap as we have had a 7kW charger on the wall for a little over 3 years, so perhaps just the earthing issue to address? Or perhaps a lot of muttering about the previous installer will occur :)
 

ufo550

Distinguished Member
That sounds like a good idea :thumbsup:

I'm not sure how much installation will occur as it's essentially a like for like swap as we have had a 7kW charger on the wall for a little over 3 years, so perhaps just the earthing issue to address? Or perhaps a lot of muttering about the previous installer will occur :)

Prior to the latest amendment of the Wiring Regulations, they had a 'get out of jail card' in domestic properties, with the words 'requirements of this regulation need not be applied..............if none (requirements) is reasonably practicable'.
 

IronGiant

Moderator
Those will be ones that came into effect within the last 3 years I assume? :) So the rod possibly should have been installed last time but he played his card...
 

ufo550

Distinguished Member
Those will be ones that came into effect within the last 3 years I assume? :) So the rod possibly should have been installed last time but he played his card...

Amendment 1 made the changes (I believe) in Feb 2020.

Edit the term reasonably practicable, was removed by the 18th Edition, not the Amendment, coming into effect Jan 2019.
 
Last edited:

noiseboy72

Distinguished Member
OK, to be clear, you can earth your home as you think fit, but what you cannot do is modify the incoming supply earthing.

You cannot just fit an earth spike and wire it to the main earth terminal without first disconnecting the neutral earth link. It is not just your property you are affecting when you do this, as in the event of a failure of the neutral - return outside of your property or street, your earth spike could become the main power return path for your whole neighbourhood! That is generally considered to be a bad thing...

I actually saw this happen in a London theatre. They had extra generators on hire to give them additional power for a large show and these were connected to a substantial earth spike via a large cable. The building earth was connected to the same point to avoid differing earth potentials. All was correctly designed, installed and tested. A few days into the run, the neutral in the shore power supply failed. All the lights in the theatre stayed on, but the earth spike actually got cherry red from the current it was passing until the power company could isolate their supply!
 

Daz1969

Active Member
My Podpoint installer added a Henley Block with a separate RCCB which bypasses the consumer unit.
 

ufo550

Distinguished Member
OK, to be clear, you can earth your home as you think fit, but what you cannot do is modify the incoming supply earthing.

You cannot just fit an earth spike and wire it to the main earth terminal without first disconnecting the neutral earth link. It is not just your property you are affecting when you do this, as in the event of a failure of the neutral - return outside of your property or street, your earth spike could become the main power return path for your whole neighbourhood! That is generally considered to be a bad thing...

I actually saw this happen in a London theatre. They had extra generators on hire to give them additional power for a large show and these were connected to a substantial earth spike via a large cable. The building earth was connected to the same point to avoid differing earth potentials. All was correctly designed, installed and tested. A few days into the run, the neutral in the shore power supply failed. All the lights in the theatre stayed on, but the earth spike actually got cherry red from the current it was passing until the power company could isolate their supply!

Actually, in the draft copy of the 18th Edition, there was a proposal to do just that; require an earth rod connected to the main earth terminal on a pme supply. Indeed this method is the norm in other Countries. As regards, it being the return path for the whole street, it wouldn't be if the installation was designed & installed correctly. But thats an issue, with rods and other underground services, as highlighted in John Wards vids, I've posted

Generators are covered in Chapter 55 BS7671, a fairly specialised field, especially in your given example. Not something I've ever been involved with. But it seems like it was poorly designed & installed.
 

booyaka

Moderator
My Rolec installer did it 2 parts.

First someone pitched up and did some extra work at the consumer unit. Added something (Can't remember what it was but he said it was his job to this bit) - Think this is a separate RCD unit (large white box with a reset RCD inside)

Then the Rolec fitters arrived - they did all the other work including the armoured cable fitting/Rolec unit etc. Super neat & tidy job / nice guys.

Earth rod was fitted under my floorboards near consumer unit (not visable) -
 

noiseboy72

Distinguished Member
BS7909 contains the specialised guidance for generators. There was no issue with the design and installation at the theatre. The problem was the failure of the main supply return path due to a pavement fire. The earth installation did not fail, it just got bloody hot!!

If you fit an earthing point to your home, you are responsible for the ongoing maintenance and testing of it. You could also become the earthing point for the rest of your street, so make sure you've made a good job of it...
 

IronGiant

Moderator
I'm not having anything to do with it, that's why a professional (I hope) is installing it :)
 

ufo550

Distinguished Member
BS7909 contains the specialised guidance for generators. There was no issue with the design and installation at the theatre. The problem was the failure of the main supply return path due to a pavement fire. The earth installation did not fail, it just got bloody hot!!

If you fit an earthing point to your home, you are responsible for the ongoing maintenance and testing of it. You could also become the earthing point for the rest of your street, so make sure you've made a good job of it...

British Standard BS 7671 is the principle guide to electrical safety in the UK.

The Health and Safety Executive holds BS 7671 in high regard, to the extent that it has written an endorsement in the introduction (of BS7671), which states that installations that comply with BS 7671 are likely to enable the requirements of the EAWR 1989 to be met. (cit BS7671).

BS7671 considers all electrical installations, as defined by its scope. Other BS standards work along side it or parallel with it.

As regards any installation, it could be you've had a good job done on the design & install, then someone else comes along and doesn't do such a good job. That doesn't make earth rods an unreasonable option. Earth rods have been installed for many years, and probably will be for many years. Indeed, from what I read, earth matts might be the future answer for EV charging. And there is still opinion that earth rods and pme will come back in future Editions, because of our failing network, earth rod may be required to supplement a DNO's earthing facility. Earth rods have their limitations, but still serve a purpose.
 

IronGiant

Moderator
What's annoying is we had a new drive installed in March, would have been an ideal time to have a mesh/mat put down.
 

IronGiant

Moderator
They replaced the additional single consumer unit that supplied the charger with a box containing a 32A RCD and a bunch of electronics and solenoids that cut the power to the charger if any interruption to the supply is detected whether that be earth, live or neutral. Additionally they fitted a cut out so that if the current entering the property gets up to 60A it will cut the supply to the charger. This to protect our rather wimpy 60A main fuse.
 

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