Home Charge Points Discussion and Suggestions [megathread]

[doats1]

I'd second that, the TWC is better made that a lot of the other units, particularly the cable and connector. At £460 it's not that expensive, either, about half the price of an Andersen (the Anderson unit costs about £995, excluding installation and the OLEV grant), or about twice the price of the cheapest charge point on the market.

Only downside with the TWC is that it still needs a Type B RCD and wiring as TT installation with an earth rod, or connecting with something like an O-PEN unit, to comply with the regs (for a 32m run down a garden I'd always go for wiring it as TT, anyway). The same installation requirement applies to quite a few other charge points though, probably the majority of those currently available, and Type B RCDs are coming down in price, they now retail for about £114, rather than the £200+ they were going for a year or so ago.

I'd third it. I was quoted by 2 EV charger fitters £800+ to fit either a Rolec or Pod Point, and that was with the OLEV discount. So I got a quote from my local electrician to fit a TWC. He quoted £200 for labour, and £100 for additional parts (cable, gland pack etc), but I managed to get all the parts for £30 cheaper which he was happy with. The wall charger cost £460, so all in it cost me £730.

I didn't need any new RCD equipment but I recently had my house completely re-wired so I guess I had all up to date RCD and earth points. Really happy with it. And I don't know if this happens to anyone else but instead of 7.4kW, I consistently get 8kW of charge.

 

[Roy W.]

I'd second that, the TWC is better made that a lot of the other units, particularly the cable and connector. At £460 it's not that expensive, either, about half the price of an Andersen (the Anderson unit costs about £995, excluding installation and the OLEV grant), or about twice the price of the cheapest charge point on the market.

Only downside with the TWC is that it still needs a Type B RCD and wiring as TT installation with an earth rod, or connecting with something like an O-PEN unit, to comply with the regs (for a 32m run down a garden I'd always go for wiring it as TT, anyway). The same installation requirement applies to quite a few other charge points though, probably the majority of those currently available, and Type B RCDs are coming down in price, they now retail for about £114, rather than the £200+ they were going for a year or so ago.

Fat fingers at work in my earlier post - the TWC costs £460, not £360 as I said earlier. Thanks to @Glan gluaisne for correcting me.

 

[simonh]

I liked the look of Andersen but decided I'd never be bothered winding the lead so neatly on a morning in winter,and I read a couple of folks who weren't too happy that the after-service. Zappi looked good but didn't like the LCD on the front as I can imagine it been useless/problematic on south-facing wall. Prices were all way over 1k with the OLEV grant.

I went with the Tesla wall charger. Worked out much cheaper overall. And, I like that it's not intelligent so not much to go wrong and no one else in control of it. Button to open port / unlatch is a nice addition. Long 7.5m lead to reach around the drive regardless of where I park.

 

[Yachtsman]

I liked the look of Andersen but decided I'd never be bothered winding the lead so neatly on a morning in winter,and I read a couple of folks who weren't too happy that the after-service. Zappi looked good but didn't like the LCD on the front as I can imagine it been useless/problematic on south-facing wall. Prices were all way over 1k with the OLEV grant.

I went with the Tesla wall charger. Worked out much cheaper overall. And, I like that it's not intelligent so not much to go wrong and no one else in control of it. Button to open port / unlatch is a nice addition. Long 7.5m lead to reach around the drive regardless of where I park.

I also went for the tesla charger, assuming better support in the event of issues. Unfortunately it doesnt benefit from the gov grant.
It seems I got a very good deal on the installation, I used a local electrician (who originally wired this house) who had previously installed several other ev chargers. Installed in the garage, 10 mtrs of conduit & cable + 40A rcd + labour £220.00 inc vat.

 

[HenryFarkas]

Hi all - ordering a M3P next week on salary sacrifice.

I got a quote for an install of an Andersen charge point yesterday - sadly I have an incredibly long garden which has the installation coming in at about £1000 and am unlikely to qualify for the OLEV grant due to not having off street parking. I do live on a private road and have a dedicated space to park, but I don't have that plot of land on my title plan, which I'm told will be a likely refusal.

In the interests of trying to not spend a huge amount of money are there any suggestions on charge point that are cheaper than the Andersen that are decent? I spoke to the installer about the Tesla Wall Connector, which is cheaper but requires a type B RCD fitting which is circa £200 and takes the cost up towards the Andersen.

Cheers!

Why do you even need a charger? Since you're quoting prices in pounds rather than dollars, I'm assuming you live in the UK. They have 230-volt electricity coming out of every wall socket. So just plug your car into any socket capable of taking 30 amps. I plug my M3 into an ordinary 120-volt socket here in the US. It charges slowly, but by morning, I've replaced all the electricity I need for my following day's driving. You have enough voltage coming from ordinary wall sockets that you should have no problem getting a full charge by the next day without any special charger.

Moderator comment - electrical standards mentioned in the post are not relevant to the OP or the UK and Ireland region

 

[Glan gluaisne]

I also went for the tesla charger, assuming better support in the event of issues. Unfortunately it doesnt benefit from the gov grant.
It seems I got a very good deal on the installation, I used a local electrician (who originally wired this house) who had previously installed several other ev chargers. Installed in the garage, 10 mtrs of conduit & cable + 40A rcd + labour £220.00 inc vat.

That's amazing, as. assuming you're house has a TN installation, rather than TT, then the required Type B RCD alone costs ~£114. The 40 A MCB and enclosure for the RCD and MCB adds another £20, the cable's around £30, the earth electrode etc adds another ~£25, so the labour was only around £30?

 

[Glan gluaisne]

Why do you even need a charger? Since you're quoting prices in pounds rather than dollars, I'm assuming you live in the UK. They have 230-volt electricity coming out of every wall socket. So just plug your car into any socket capable of taking 30 amps. I plug my M3 into an ordinary 120-volt socket here in the US. It charges slowly, but by morning, I've replaced all the electricity I need for my following day's driving. You have enough voltage coming from ordinary wall sockets that you should have no problem getting a full charge by the next day without any special charger.

This is the UK and Ireland forum, so we have to abide by the regulations that apply here, just as I'd guess you have to abide by the regulations that apply in your building codes.

We have a completely different electrical system here, and do not use the split phase, centre ground, system that is used in North America. Here we use a single phase, 230 VAC referenced to nominal ground, system, so unlike North America, where the most you can get is 220 VAC between phases, 110 VAC from either phase to ground, our system is potentially (no pun intended) more dangerous under fault conditions, as the car body could, if for example the incoming supply had a PEN conductor fault, rise up to the full mains supply voltage of ~230 VAC (in theory it could get to the max tolerance on that, which would be 253 VAC relative to local earth).

FWIW, we do not have domestic sockets capable of delivering anything close to 30 A, either. Our outlets are rated at 13 A maximum, 10 A continuous. Some parts of Europe have something similar to the North American "dryer" outlets, but not the UK or Ireland.

 

[doats1]

Why do you even need a charger? Since you're quoting prices in pounds rather than dollars, I'm assuming you live in the UK. They have 230-volt electricity coming out of every wall socket. So just plug your car into any socket capable of taking 30 amps. I plug my M3 into an ordinary 120-volt socket here in the US. It charges slowly, but by morning, I've replaced all the electricity I need for my following day's driving. You have enough voltage coming from ordinary wall sockets that you should have no problem getting a full charge by the next day without any special charger.

The UMC still won’t get up to 7kW because you won’t get 32A from a wall socket. So unless you get a special commando socket and UMC adapter for it, it’s almost the same as what you’d get stateside.

 

[Yachtsman]

That's amazing, as. assuming you're house has a TN installation, rather than TT, then the required Type B RCD alone costs ~£114. The 40 A MCB and enclosure for the RCD and MCB adds another £20, the cable's around £30, the earth electrode etc adds another ~£25, so the labour was only around £30?

Im no electrician so i dont know what TT & TN installation means.
The house is only 6 yrs old & was wired by the local electrians company, fairly large 8 employees.
The main electricity rcd trip unit is located in the garage so 40A rcd fitted into existing unit.

 

[Glan gluaisne]

Im no electrician so i dont know what TT & TN installation means.
The house is only 6 yrs old & was wired by the local electrians company, fairly large 8 employees.
The main electricity rcd trip unit is located in the garage so 40A rcd fitted into existing unit.

Perhaps worth doing some checking, just to be 100% sure that things are wired safely. If the house is only 6 years old, it's almost certainly has a TN incoming supply, most probably TN-C-S. This means that the protective earth (PE) is provided by a connection to the incoming neutral conductor (called the protective earth and neutral, PEN) at the company fuse. You can check this by looking at that big fuse head, if it is TN-C-S there will be a fairly thick green and yellow wire connected to the right hand side of the fuse holder (often this fuse holder is marked "100 A"). There's a slim chance that it's TN-S, in which case the green and yellow wire will be connected to the cable underneath the fuse holder (same regs apply for both TN-C-S and TN-S).

Assuming that the supply is TN-C-S, also often referred to as protective multiple earth, PME, then the minimum requirement for installing a Tesla wall connector would be an over-current protected supply from the main incoming supply, with typically a 40 A over-current device, plus a Type B RCD, to provide earth leakage protection with the required DC current tolerance, plus some form of protection against an open PEN fault. The latter can either be an earth electrode that is connected to the charge point PE connection (so isolated from the main house PE), which is acceptable if there is no possibility of the charge point earthing system being within touching distance of the house earthing system. Alternatively, an open PEN protection device needs to be installed, such as the matt:e O-PEN unit.

The Tesla wall connector, in common with several other charge points, doesn't (yet) have UK-compliant internal protection against both DC earth leakage and open PEN faults, hence the reason that this additional stuff is required.

This is all detailed in the wiring regulations, BS7671:2018, Amendment 1, Section 722. Your electrician should have completed an Electrical Installation Certificate (EIC) and also submitted a building regulations Part P notification (this is notifiable work) and that certification should state that the installation complies with the wiring regulations.

If you want to check, then if you can post photos of the incoming supply (to check that it's TN-C-S), the connection from the charge point to the supply (should be a small enclosure where the charge point cable terminates) and also the area around the charge point (to check there is an earth electrode installed) then it should be a few seconds work to see what's what from photos.

 

[Yachtsman]

Perhaps worth doing some checking, just to be 100% sure that things are wired safely. If the house is only 6 years old, it's almost certainly has a TN incoming supply, most probably TN-C-S. This means that the protective earth (PE) is provided by a connection to the incoming neutral conductor (called the protective earth and neutral, PEN) at the company fuse. You can check this by looking at that big fuse head, if it is TN-C-S there will be a fairly thick green and yellow wire connected to the right hand side of the fuse holder (often this fuse holder is marked "100 A"). There's a slim chance that it's TN-S, in which case the green and yellow wire will be connected to the cable underneath the fuse holder (same regs apply for both TN-C-S and TN-S).

Assuming that the supply is TN-C-S, also often referred to as protective multiple earth, PME, then the minimum requirement for installing a Tesla wall connector would be an over-current protected supply from the main incoming supply, with typically a 40 A over-current device, plus a Type B RCD, to provide earth leakage protection with the required DC current tolerance, plus some form of protection against an open PEN fault. The latter can either be an earth electrode that is connected to the charge point PE connection (so isolated from the main house PE), which is acceptable if there is no possibility of the charge point earthing system being within touching distance of the house earthing system. Alternatively, an open PEN protection device needs to be installed, such as the matt:e O-PEN unit.

The Tesla wall connector, in common with several other charge points, doesn't (yet) have UK-compliant internal protection against both DC earth leakage and open PEN faults, hence the reason that this additional stuff is required.

This is all detailed in the wiring regulations, BS7671:2018, Amendment 1, Section 722. Your electrician should have completed an Electrical Installation Certificate (EIC) and also submitted a building regulations Part P notification (this is notifiable work) and that certification should state that the installation complies with the wiring regulations.

If you want to check, then if you can post photos of the incoming supply (to check that it's TN-C-S), the connection from the charge point to the supply (should be a small enclosure where the charge point cable terminates) and also the area around the charge point (to check there is an earth electrode installed) then it should be a few seconds work to see what's what from photos.

Hi Glan, unfortunately thats all double dutch to me, but if it means anytbing they did provide a 2 page certificate after completion.

 

[Glan gluaisne]

The certificate, which sounds like an EIC, should have all the relevant details, including the RCD type and earthing arrangement. Perhaps easier if you could just post a couple of photos, as they will show what's been done. The RCD will have three symbols on the front if it's a Type B, a sine wave, a broken sine wave and a solid line with a dashed line. The photo below shows the common types of RCD, and the three symbols you're looking for are those at the top of the first three columns, the key one being the "Smooth DC" one. These symbols may be quite small, and are often in grey against the white background, so not that easy to see sometimes:

 

[MrBadger]

Installed in the garage

If you charge your car in the garage, then electrical regulations will be less strict than if you ere charging your vehicle outdoors and you may be in contact with bare ground. The regulations that @Glan gluaisne mention are to protect from faults when you are in contact with the car and the outside ground. If you are charging inside the garage, similar faults may still occur, but the route back to earth is via the house wiring rather than bare ground - in the same way that any electrical circuit in the house would. So two scenarios, two different ways of handling the fault condition.

 

[Glan gluaisne]

Depends on the garage type and location, as well as the electrical installation. The exact same criteria apply with regard to exposed conductive parts though, as does the DC tolerant earth fault protection requirement. The one possible difference is that it may be possible to not fit some form of open PEN protection in some circumstances, although that's far from being certain. The main concern would be that the earth fault protection device is DC tolerant, so it will operate in the presence of the DC earth leakage that is always present when a charge point is in use (from the control pilot signal).

 

[Yachtsman]

If you charge your car in the garage, then electrical regulations will be less strict than if you ere charging your vehicle outdoors and you may be in contact with bare ground. The regulations that @Glan gluaisne mention are to protect from faults when you are in contact with the car and the outside ground. If you are charging inside the garage, similar faults may still occur, but the route back to earth is via the house wiring rather than bare ground - in the same way that any electrical circuit in the house would. So two scenarios, two different ways of handling the fault condition.

You have both got me concerned now so i will take a look at the certificate & the rcd. Yes I only charge in the garsge, I have a 2.5 mtr cable & the charging port is less than 1 mtr from the charger. The charger is at the back of the garage & I reverse in.
The garage has a concrete floor & is 4 inches below the house floor!

 

[Glan gluaisne]

You have both got me concerned now so i will take a look at the certificate & the rcd. Yes I only charge in the garsge, I have a 2.5 mtr cable & the charging port is less than 1 mtr from the charger. The charger is at the back of the garage & I reverse in.
The garage has a concrete floor & is 4 inches below the house floor!

That's really useful information, as one key consideration when it comes to whether open PEN protection might be needed is whether or not the charge point tethered cable can reach outside the garage. From what you've described it cannot, so for an attached garage that shares the same earthing configuration as the house, then it seems likely that open PEN protection may not be required (although the regs still say it should be included - common sense, together with the need to not be able to touch two different earthing systems, over rules the regs in this case).

The most important safety device is the RCD. Because there will always be some DC earth leakage (it's a function of the way the signalling system works between the car charger and the charge point), the RCD has to be a type that will still operate in the specified time and at the specified earth fault leakage current, in the presence of a steady DC leakage. Type AC and type A RCDs tend to be blinded by any DC leakage, and some just stop working under these conditions, meaning that they may not detect a fault and turn off the power. A type B RCD is DC tolerant, at the level of DC leakage from a charge point installation, so will still work properly, and ensure safety by isolating the power, if there were to be an earth fault.

You may find that your installation has an RCBO, that provides Type A (typically) RCD protection with Type B over-current protection. The use of Type B as a trip time characteristic for the MCB part of the RCBO can be confused with the Type B leakage current bit - they should have used different terms.

 

[Yachtsman]

That's really useful information, as one key consideration when it comes to whether open PEN protection might be needed is whether or not the charge point tethered cable can reach outside the garage. From what you've described it cannot, so for an attached garage that shares the same earthing configuration as the house, then it seems likely that open PEN protection may not be required (although the regs still say it should be included - common sense, together with the need to not be able to touch two different earthing systems, over rules the regs in this case).

The most important safety device is the RCD. Because there will always be some DC earth leakage (it's a function of the way the signalling system works between the car charger and the charge point), the RCD has to be a type that will still operate in the specified time and at the specified earth fault leakage current, in the presence of a steady DC leakage. Type AC and type A RCDs tend to be blinded by any DC leakage, and some just stop working under these conditions, meaning that they may not detect a fault and turn off the power. A type B RCD is DC tolerant, at the level of DC leakage from a charge point installation, so will still work properly, and ensure safety by isolating the power, if there were to be an earth fault.

You may find that your installation has an RCBO, that provides Type A (typically) RCD protection with Type B over-current protection. The use of Type B as a trip time characteristic for the MCB part of the RCBO can be confused with the Type B leakage current bit - they should have used different terms.

The garage is an integral part of the house.
The tethered charger cable will not reach outside (open air) but would just reach inside the house via a internal door into the utility room if that matters.
The main electricity supply (& smart meter) enters the house (not garage) & is imediately on the other side of the garage wall that the rcd trip unit is located.
Does this help?

 

[Glan gluaisne]

The garage is an integral part of the house.
The tethered charger cable will not reach outside (open air) but would just reach inside the house via a internal door into the utility room if that matters.
The main electricity supply (& smart meter) enters the house (not garage) & is imediately on the other side of the garage wall that the rcd trip unit is located.
Does this help?

Yes, that's great, it confirms that the common sense approach would be to not fit open PEN protection, which would be either an earth electrode with the PE of the charge point connected to that, or to use an open PEN protection device, like the O-PEN box.

The main concern is whether or not a DC tolerant RCD has been installed, though. Although it's OK in your circumstances to not include open PEN protection, the installation does still need to be protected from earth faults that may present an electric shock risk.

Some charge points include DC leakage protection that meets the requirement, but the Tesla connector doesn't have this, so needs to be protected with the right type of RCD. There isn't a Type B RCBO available (a single unit that provides both the RCD function, for protection from earth faults, and over-current protection, like a fuse) so the installation should have two separate protection devices where it is connected to the house supply (often in a small separate enclosure). The normal arrangement would be to have a Type B RCD, which will be a large device, much wider than a normal circuit breaker (usually three times wider), together with a miniature circuit breaker (MCB) rated at typically 40 A. These two devices should normally be mounted side by side in the same enclosure.

The RCD will look different to anything else, because of it's width. Type B RCDs look like this (note the small symbols just to the right of the reset lever):

Next to it will probably be the over-current protection device, an MCB that looks similar to this:

If you have a single device, that looks something similar to this:

then it's a 40 A Type A RCD function RCBO, that is not safe to use with a charge point, as it may be blinded by the residual DC earth leakage that is always present when the charge point is connected to the car charger.

 

[Yachtsman]

Yes, that's great, it confirms that the common sense approach would be to not fit open PEN protection, which would be either an earth electrode with the PE of the charge point connected to that, or to use an open PEN protection device, like the O-PEN box.

The main concern is whether or not a DC tolerant RCD has been installed, though. Although it's OK in your circumstances to not include open PEN protection, the installation does still need to be protected from earth faults that may present an electric shock risk.

Some charge points include DC leakage protection that meets the requirement, but the Tesla connector doesn't have this, so needs to be protected with the right type of RCD. There isn't a Type B RCBO available (a single unit that provides both the RCD function, for protection from earth faults, and over-current protection, like a fuse) so the installation should have two separate protection devices where it is connected to the house supply (often in a small separate enclosure). The normal arrangement would be to have a Type B RCD, which will be a large device, much wider than a normal circuit breaker (usually three times wider), together with a miniature circuit breaker (MCB) rated at typically 40 A. These two devices should normally be mounted side by side in the same enclosure.

The RCD will look different to anything else, because of it's width. Type B RCDs look like this (note the small symbols just to the right of the reset lever):

Next to it will probably be the over-current protection device, an MCB that looks similar to this:

If you have a single device, that looks something similar to this:

then it's a 40 A Type A RCD function RCBO, that is not safe to use with a charge point, as it may be blinded by the residual DC earth leakage that is always present when the charge point is connected to the car charger.

Glan,
I really appreciate the advice from both of you, youve certainly opened my eyes.
I will take a look tomorrow & if you dont mind I may reply with photos.
How did the tesla wall unit get approved for use in the uk? Theres me thinking I was choosing the best product but maybe not.
I hope others read these comments & learn from them.

 

[Glan gluaisne]

Glan,
I really appreciate the advice from both of you, youve certainly opened my eyes.
I will take a look tomorrow & if you dont mind I may reply with photos.
How did the tesla wall unit get approved for use in the uk? Theres me thinking I was choosing the best product but maybe not.
I hope others read these comments & learn from them.

Yes, photos would be very useful, please.

The Tesla wall connector is very good, probably one of the best units around, but, like many of these units, it is made for a global market, so cannot hope to meet all the different national requirements.

For example, in North America, their 220 VAC system is radically different to our 230 VAC system, as neither of the live connections is 220 V above earth, it's split, so that both live conductors are only 110 V above earth.

Here in the UK we have a system where the second live conductor, the neutral, is connected to the local earth, somewhere not too far from the property supply. This means that the remaining live terminal, the one we refer to as the line, is 230 V above earth, rather than the 110 V above earth they have in North America.

Because the charge point manufacturer doesn't know what sort of installation the unit will be fitted to, there's no easy way to make a one-size-fits-all design. For example, some rural houses in the UK have TT installations, where there is no PE provided on the incoming supply cable and the house installation has a local earth electrode, to which everything is connected. This type of installation doesn't require open PEN protection, as there is no PEN conductor.

Arguably, all charge points should include DC tolerant earth leakage fault protection, and some now do. I've just built one (see here: DIY charge point ), using off-the-shelf-parts, that has both open PEN and DC tolerant earth leakage fault protection, and there are several other makes of charge point available in the UK now that have all the required protection built in. I don't know for sure, but I believe that the next generation of Tesla wall connector may have integral protection, although I've not yet read the spec for it.