Charger installation, is this ok

Possibly, but as a minimum you will need a charge point that has integrated open PEN fault protection, plus DC tolerant earth leakage protection, and you will need to ensure that the RCD feeding the charge point circuit is a Type A, and not a Type AC, and that there are not two RCDs in series without some form of selectivity.

The installer will do a survey as a part of the job, so will assess whether there is enough spare capacity on that supply, or whether another supply needs to be run to the charge point. In general it's better to run a separate supply from the meter tails, rather than take the supply from the main house CU, because charge points run for hours on end, and thus tend to heat up the MCB feeding them. There is also a possible selectivity issue with RCDs, as the feed from the CU (if using that approach) must come from a non-RCD protected way if there is another RCD downstream from it, or some other means must be used to provide RCD selectivity. Your installer should sort all this for you, just explain that you would prefer to have no outside cabling visible, if at all possible.

Ronce said:

There is no option to run any cabling from the house or the meter

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Installers are used to dealing with the most awkward arrangements, particularly the common arrangement of putting the meter and CU under the stairs in older houses. Daft place to put it, really, and probably the most awkward when it comes to adding additional circuits.

The key points are:

• The supply cable to the charge point must be fed from a supply that can take an additional load of 32 A
• The supply cable must be over current protected, and if not armoured cable must also be RCD protected.
• The charge point must have DC tolerant earth leakage protection (either built in, or via a supply protected with a Type B, EV or F RCD)
• If the installation is TN, and not TT, then the charge point must have open PEN fault protection (either built in, or via a PEN fault protection device in the supply)
• The charge point must be protected by a manually resettable RCD or RCBO, with a Type A characteristic, unless protected by a separate Type B, EV or F RCD.
• Any RCD protection must be arranged to ensure selectivity if there is more than one RCD in series. For example, if the garage 10mm² supply is fed from the main CU, then it must be supplied by a non-RCD protected MCB, if there is another RCD in the circuit. The alternative is to fit some other form of selectivity, by swapping out RCD types, but it's far easier to just avoid series RCDs if at all possible.

I would just discuss this all with your chosen installer. There are ways and means to supply charge points neatly in pretty much every situation, and any installer that's done a few will have a small arsenal of tricks and tips as to how best to make sure an installation is safe and neat.

Ronce said:

OK but when you say awkward I mean there is no possible means to connect another cable from the house to the garage at the end of the drive, no one wants to actually come out they just ask for pictures that is all well but like I've said you cannot run another cable and I don't want to be in a situation when he turns up and says he can't do it, it's also 20 meters away from the house

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I doubt you’ll get any installer wanting to visit to survey and quote unless you are happy to pay for a survey fee - they pretty much always ask for photos and details.

The issue with your existing arrangement is that it is all existing, and the installer will become responsible for sorting out any issues when reusing the connection from your consumer unit, the 10mm cable, and garage CU too. This is why most also insist on using a direct connection from the meter with a separate small stand-alone CU for the EVSE installation. That’s not to say there is anything wrong with your intended approach provided all aspects of the regs and any rectification/improvement works needed are taken care of.

In your case I would take lots of photos, and include plenty of detail about the existing arrangements, and send these to the installers you are wanting to quote and see what they say. I’d suggest you may be better choosing electrical contractors over the lines of manufacturers, as you are more likely to be able to discuss the installation details with someone who can look at the requirements objectively, rather than simply having a fixed installation method from which they will not deviate.

Ronce said:

So putting aside installers who don't want to install anything other than new due to becoming responsible for the entire equipment , a resinbond drive that is edge to edge with no means to get under it without damage is it possible to connect to what I have or not ?

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The drive we went under was resin bonded, as it happens.

No one here on an internet forum can sign off your installation as being compliant and safe, especially not when those of us trying to help are guessing as to what you may really have from your description. The requirements that need to be met are as I detailed earlier in this thread, and rather than deal with charge point installers my advice would be to try and find a good local electrician, and worth with them to come up with a solution. Any competent electrician can install a charge point, although if you are claiming the grant then they do have to register and do some paperwork. For a difficult installation you may well be better off using a trusted local electrician.

The charge point manufacturers that offer an installation service often sub-contract work out, but they are always taking a cut, so are acting as middle men, and often they try and cut costs by relying on the customer taking photos, rather than doing a proper survey. The majority of electricians will want to look at a job before giving a quote, so you get a chance to discuss your concerns and what you would prefer. In your case that seems to be your best option, and it may be worth considering not bothering with the grant, if that means using a local electrician that doesn't want the hassle of registering for it. Doing that means you have a greater choice in terms of charge points, to some extent, if you don't need the smart functionality that grant-funded charge points must have.

The challenge for you will be finding a good local electrician. Best bet is to ask around, as a personal recommendation is always better than just cold-calling someone.

Ronce said:

I just asked if what I had was possible. Not how others have installed and how its not impossible, I have explained cable cannot be run from Meter or comsumer, the drive is edge to edge with no mean to get under it without damage only to be told that someone else got under one so I asked how ?

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As above, "how" means knowing a lot more about your present installation. I listed some of the things that anyone needs to know to give you sound advice. If you start by trying to answer some of those questions, or, perhaps, post some photos of what exists at either end at the moment, then we may have some chance of giving advice that may be useful.

I told you how I've got under drives using a mole or a pipe and hose. The former is so common that most hire stores have moling rigs that can be hired by the day, the latter is an old school method that works in some soil types. We have no way of knowing whether either method could be used for your drive, as we don't have the benefit you have of knowing what it looks like, and whether either technique might work or not.

This is all about information. If you can provide a bit more information about your existing installation then it may be possible to give more focussed advice. For example, if it turns out that your garage supply is already TT, then there's no requirement to provide open PEN fault protection, as there is no PEN to develop a fault.

The main consumer is a hager, a year old, it has a 63amp AC cd 263 u RCD, it has 2 x 20amp trips mtn120 b20, 2 feeds to the garage 1 I from what I can see is standard twin and earth run though the cavity to a box on the outside wall from there its 2.5 armoured straight to inside of the garage to a standard internal isolation socket that runs the electric garage door and that is it its connected to a mtn116 - b16 MCB, then I have a 2nd feed that is connected to a mtn140 - b40 mcb , this is 10mm 3 core ( black,brown,grey) pva swa straight from the main consumer with an internal gland to the garage consumer again with an internal gland , this is an AXIOM, it had a 63amp rcd, rcd63br, then a 32amp cub32sp (not used) a 16 amp cub16sp ( 2 x double socket 1 x interernal 1 x external ) a 6 amp cub6sp ( 1 internal light 2 x external carriage lights on a pir ) both armoured cables are run underground, there is no earth spike/rod , in the meter box there is a 100amp fuse , one red 1 black out to the digital meter reader and an earth I guess going to the main consumer then 2 grey out of the meter to again I guess the main

Ronce said:

The main consumer is a hager, a year old, it has a 63amp AC cd 263 u RCD, it has 2 x 20amp trips mtn120 b20, 2 feeds to the garage 1 I from what I can see is standard twin and earth run though the cavity to a box on the outside wall from there its 2.5 armoured straight to inside of the garage to a standard internal isolation socket that runs the electric garage door and that is it its connected to a mtn116 - b16 MCB, then I have a 2nd feed that is connected to a mtn140 - b40 mcb , this is 10mm 3 core ( black,brown,grey) pva swa straight from the main consumer with an internal gland to the garage consumer again with an internal gland , this is an AXIOM, it had a 63amp rcd, rcd63br, then a 32amp cub32sp (not used) a 16 amp cub16sp ( 2 x double socket 1 x interernal 1 x external ) a 6 amp cub6sp ( 1 internal light 2 x external carriage lights on a pir ) both armoured cables are run underground, there is no earth spike/rod , in the meter box there is a 100amp fuse , one red 1 black out to the digital meter reader and an earth I guess going to the main consumer then 2 grey out of the meter to again I guess the main

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Thanks, that helps a great deal.

Is there space by the main CU to do as suggested by @idiotzoo and reconfigure the 10mm² SWA so it can connect to a small connection box fed from the tails, via a couple of henleys? That would then separate out the charge point supply from the domestic supply, and remove the series RCD problem that I think you have at the moment. I'm assuming that the 40 MCB feeding the 10mm² SWA is RCD protected in the main CU, is that right?

Are you sure that the main fuse is 100 A, or is that just the marking on the fuse holder? All the fuse holders are marked 100A, as that's the fuse holder rating, but the fuse fitted maybe either a 60 A, 80 A or 100 A. As the Hager board was fitetd very recently, the main fuse type and rating will be on the EIC for that, and you should have a copy of that. With luck, the actual fuse fitted may be marked with an additional label, too (helps a lot when this is done, but it's not universal practice). If the fuse is either 80 A or 100 A it should be fine, but if it's 60 A then you may need to talk with the DNO about getting it uprated, if possible. Your installer needs to inform the DNO of the charge point installation anyway, as that's a requirement.

It sounds as if you may be able to re-jig some of the garage internal wiring so that you can re-use that 10mm² SWA feed as a dedicated charge point supply. Best bet would be to see if all the existing garage loads can be run from the 2.5mm² SWA radial. Depends on the loads you have there, but that could run a small CU with 16 A power and 6 A lighting circuits OK. That would then mean the 10mm² SWA could become a dedicated charge point supply cable, making things a fair bit neater.

I still think you would probably get more sense out of talking with a local electrician than one of the big installation companies, as from what you've written above it does seem as if there may be a way to re-jig what you have to re-use the existing cables. A local electrician may well be more flexible and open to doing the additional work needed to either end of the cables to make this option work well.