Adding a garage supply inc EV charger

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The price off the shelf at trade basically works out the same as what it would be if I was to claim the money back
 
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Hi just wondered if I could have some advice please without having my head bitten off about having power installed I'm my garage, I have posted on another well known forum and have had allsorts of abuse without actually getting any advice so is this forum for DIY or is it just for " qualified electricians to chat to each other " as I have been told on the other forum !?

Were you just looking for the 50p argument, or the full £5 worth of abuse?
 
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I think its more this 40 or 50amp mcb in the main CU and the A type rcd that I'm worrying over that's all
Home charge units are 32 amps. The circuit usually is 32A as well, but doesn't have to be - the MCB is for protection of the cable, not the charge unit. Larger ratings of both are possible.

Type A RCD is the minimum required for most installations, assuming one is actually required at all.

Some charge units may need a particular type of RCD externally, others have it all in the unit.
The cable supplying it may require an RCD depending on the type of cable used, how it's installed and what type of supply the property has got. It may not need any RCD.
 
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Ah ok I see, thank you so I'm going to have Zappi installed and a Harvi hub !? I believe they have RCD and pens protection already built in so no earth spike required either and the hub part can limit the amp draw I think !? So basically if its done with the 40 amp mcb to the garage CU( 10mm swa from cu to cu ) that has the A type RCD the charger will be fine coming from the 32 part of that ?
 
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Also I keep seeing "DNO notifiable' Is this something I have to do once its installed or does the electrician do all that? If so do I have to sign something for him ect so I know hes done it ?
 
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SWA on a TN-C-S or TN-S supply does not need any RCD. If installing the Zappi, it would be preferable to have a non-RCD circuit for it in SWA throughout.

The Zappi product includes all of the required RCD and DC leakage protection.
Harvi is an optional device to connect current monitoring wirelessly, rather than using a cable.
The hub is a separate item required to connect the Zappi, Harvi and other devices from that manufacturer to the internet, so you can use the smartphone app to control and monitor it and various other things.

New circuits and consumer units are notifiable work under the Building Regulations (Part P). That can either be done direct to building control or by an electrician registered with one of the schemes such as NICEIC or NAPIT.

New circuits should also have an installation certificate as required by BS7671 which is completed by the installing electrician. That will contain full details of the work done and all test results for the new circuits installed.

EV chargers are additionally notifiable to the DNO for load management purposes. Example: https://www.ssen.co.uk/Connections/EVconnections/
The arrangement there is that the installer does a load assessment for the existing installation. If the total load including the new charger is less than 60A, the install can usually go ahead with just the notification.
If it's more than 60A, DNO confirmation must be obtained before installing, and in some cases additional works will be required by the DNO to upgrade/alter the network to accommodate the additional load. That may or may not be chargeable depending on who the DNO is and various other factors.

Regardless of total load, some locations won't be usable without further works, such as looped supplies or blocks of flats where the building has a single supply and multiple EV units are required.

All of the above should be done by the EV installer. That's why installing EV charge outlets is expensive.
 
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OK that makes sense, so basically the electrician will do all the required stuff, just on the rcd bit, so is it still ok to come of the 32 on the mini consumer or would he need to change it ?
 
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so basically the electrician will do all the required stuff,
Should do those things - don't assume anything.
Plenty of people around that will sling in any old rubbish, take a large payment in cash and ride off into the sunset on their horse never to be seen again.

If a CU is being installed in the garage, a supply to it in SWA protected by an appropriate fuse or possibly MCB, with the CU having a main switch, one or more RCBOs for the garage loads, and a 32A MCB for the EV charger would be a sensible arrangement.

However it's up to whoever installs it - there are many ways to do things, more than one of which may be correct.

The price off the shelf at trade basically works out the same as what it would be if I was to claim the money back
You don't claim the grant, it's done by the OZEV approved installer.
As an example, if the total including installation was £1000, you pay them £650 and they get the £350 from the DVLA at a later date.
 
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Yeah so by looks of it , it'll be 40amp mcb ( non rcd side ) in the main, 10mm SWA to a smaller CU in garage that has a 40,32,16,6 mcbs and a A Type RCD the 32 for car 16 for sockets and 6 for lights, 40 won't be used

With the grant then does that still work with me buying the charger myself, I'm only paying him for the install and testing
 
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The grant is only available via an OZEV registered installer supplying and installing everything.
There is no option for buying the charger yourself.

smaller CU in garage that has a 40,32,16,6 mcbs and a A Type RCD the 32 for car 16 for sockets and 6 for lights, 40 won't be used
Main switch, 32A MCB EV, 20A RCBO sockets, 6A RCBO lights.

No sense in buying a 40A MCB that won't be used, a 16A circuit will use the same cable as a 20A, and a single RCD for both sockets and lights will mean any fault with something plugged in such as a power tool also cuts the lighting off at the same time. EV point doesn't need an RCD.
 
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A final point - for people who are VAT registered, the choice is either claim the VAT on the EV install, or claim the OZEV grant. You can't do both.
 
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Yeah so with me buying it and paying for the install works out around the same as if I paid the extra and dome the grant, the chap is registered and has they testing equipment and what I meant about the garage cu is that is how it comes, with all that already in, the type A rcd, 40,32,16 and 6 mcb, I guess he can take the 40 out and just use 32 direct for the charger and use the rcd for the other 2 maybe , I'll just have to leave him too it, I think my main concerns have been answered thank you, I was just worried something had gone a miss and might cause a problem
 
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Home charge units are 32 amps. The circuit usually is 32A as well, but doesn't have to be - the MCB is for protection of the cable, not the charge unit. Larger ratings of both are possible.

Type A RCD is the minimum required for most installations, assuming one is actually required at all.

Some charge units may need a particular type of RCD externally, others have it all in the unit.
The cable supplying it may require an RCD depending on the type of cable used, how it's installed and what type of supply the property has got. It may not need any RCD.
Most manufacturers of EVSEs recommend a 40A device with a 7kW charge point so that it's not running at its nominal rating the whole time.
 
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