RCBO for EV Charger

[ScottishGasMan]

Putting together a rough shopping list for getting EV charger.

Going for a Zappi Single phase 7Kw charger. The outside wall it will mount on is directly behind the Electric meter located inside, although the CU is in a different room.

So should be able to get rear entry to EV Charger box, into the elec meter area for the sake of connecting the CT clamp. Then with a little luck, I left a couple of conduits between the meter cupboard and the cupboard with the CU in it, so hopefully be able to draw a supply cable through without much issue and without having to empty a room and take up laminate etc.

Question is, currently all the breakers in the CU are Hager RCBOs. The Zappi has a 30mA Type A RCD + 6mA DC protection.

So to try get a cable through existing conduit, and because it's rear entry to the outside unit, there's no exposed cable, so was hoping not to use any SWA. But there will be some length of cable behind the chipboard duct the CU is mounted on <50mm from the surface.

So can anyone recommend an RCD/RCBO suitable for use with that type of charger to protect the supply cable? Or would it be better to just mount the cable on the surface of the chipboard and keep it visible with only MCB protection?

 

[winston1]

As it is a new circuit it is notifiable and probably not cost effective to DIY. Let a sparks do it and make those decisions.

 

[davelx]

You probably only need an MCB, depending on the cable type or routing.
But as Winston says....

 

[flameport]

40A Hager B curve Type A RCBO, which will be the 'tall' version as they only make the compact ones up to 32A.
Or if the cables are on the surface of the chipboard, and there are no concealed ones less than 50mm from the wall surface, a 40A Hager MCB.
Preferably installed in the CU with at least one space between the new MCB/RCBO and the existing devices.

All new Hager devices will fit in Hager consumer units from the last 30+ years.

If you buy the Zappi now, it will need a separate Hub to go with it.
If you wait a couple of weeks, you can get the new version with the hub built in.

 

[ScottishGasMan]

40A Hager B curve Type A RCBO, which will be the 'tall' version as they only make the compact ones up to 32A.
Or if the cables are on the surface of the chipboard, and there are no concealed ones less than 50mm from the wall surface, a 40A Hager MCB.
Preferably installed in the CU with at least one space between the new MCB/RCBO and the existing devices.

All new Hager devices will fit in Hager consumer units from the last 30+ years.

If you buy the Zappi now, it will need a separate Hub to go with it.
If you wait a couple of weeks, you can get the new version with the hub built in.

Didn't know there was a new version with the hub thanks, will hold off for now, can afford a few weeks, as waiting time for them direct is 6 weeks I think, and car arrives not much after that.

Is the space between them in the CU due to heat being produced with a prolonged high load?

It's a mate that will be testing/making final connection, as he's got the electrical certs, will need to be him that fills out DNO form as well.

But he's not an electrician by trade, gas by trade and done electrical courses etc last year but very limited experience, hence I'm wanting to have everything planned out and ordered, cables run in etc before he comes down to do it (he's not local)

 

[ScottishGasMan]

40A Hager B curve Type A RCBO

Also, may aswell ask to compare to his thoughts, he said 6mm cable, which I assumed was fine (run is approx 4 to 5m) I had thought a 32A rcbo/mcb as it would be run in a conduit (not in a wall but under floor)

But would a 32A trip as obv very close to running capacity of the charger and potentially could be running for 10 hours at a time

 

[Adam_151]

40A Hager B curve Type A RCBO, which will be the 'tall' version as they only make the compact ones up to 32A.

I was about to come on here and tell you that you can now... I've seen reference made to them, as part number ADS340G.... but I was just going to get a picture, but cant actually find anything on the hager site, which is odd, unless places have just assumed it should exist and what the part number would be going off others in the series.

I was convinced that they had started to become a thing!

 

[flameport]

Is the space between them in the CU due to heat being produced with a prolonged high load?

Yes, and that's why a 40A is more desirable than a 32A - less heat created as it won't be running at it's maximum all the time.

If there is no space, then an alternative it to place it next to a circuit which which will only be lightly loaded, such as lighting.

 

[Risteard]

40A Hager B curve Type A RCBO, which will be the 'tall' version as they only make the compact ones up to 32A.
Or if the cables are on the surface of the chipboard, and there are no concealed ones less than 50mm from the wall surface, a 40A Hager MCB.
Preferably installed in the CU with at least one space between the new MCB/RCBO and the existing devices.

All new Hager devices will fit in Hager consumer units from the last 30+ years.

If you buy the Zappi now, it will need a separate Hub to go with it.
If you wait a couple of weeks, you can get the new version with the hub built in.

RCDs for Electric Vehicle Supply Equipment are required to interrupt all live conductors, so the RCBO mentioned wouldn't be appropriate.

 

[flameport]

The Zappi has the RCD built in, and that does disconnect all conductors.

The RCBO in the consumer unit is only required for the cable installation method.

 

[Risteard]

The Zappi has the RCD built in, and that does disconnect all conductors.

The RCBO in the consumer unit is only required for the cable installation method.

True, although the RCD in the Zappi is not to BS EN 61008 or BS EN 61009.

 

[winston1]

It's a mate that will be testing/making final connection, as he's got the electrical certs, will need to be him that fills out DNO form as well.

But he's not an electrician by trade, gas by trade and done electrical courses etc last year but very limited experience, hence I'm wanting to have everything planned out and ordered, cables run in etc before he comes down to do it (he's not local)

It does not work like that. He (not you) has to sign a form that says he designed and installed it. You (not he) need to inform your local authority before you start and pay their fee.

 

[markyd1]

What size main fuse do you have?, what type of earthing system do you have? And i will tell you what you dont have someone doing the install properly

 

[ericmark]

Not a clue as to rules in Scotland, however my understanding is to get government grants you need to have it installed by some one who has done the courses on EV installations and can sign the forms. So even as a time served electrician I would still need to get some one to install it for me, or forget about grants and rules and simply fit a 32 amp socket.

This to me is the worrying bit, I can say I am fitting a 32 amp socket for a welding set, buy a 7 kW charging lead, and install my own charging point without using some one who has done the course and understands the safety aspects of fitting a EV charge point.

I could in my garden fit a charge point far enough away from the house to safely use a TT supply and it is not on a route which would be taken by any visitors to the house, but my house is unusual having a drive way to rear of house, most people park their car where visitors to the house would pass it.

Having done it right once and involved the LABC I am not convinced they would know if I did it wrong, and the notification is suppose to be a traceable record, which when I wanted a copy they could not trace. So in real terms it is no more than a tax.

As to warrant system I don't know, I don't live in Scotland, but in England and Wales those fitting EV points need more than just being a scheme member, so it seems pointless half registering the work, either do it properly, or do it completely under the radar, as said the latter worries me, even done professionally who would put a charge point across a pedestrian access point? And as to using an earth rod, clearly the metal roller shutter doors are far to close to the cars at the charge point to have a different earthing system. Looks good, and was a great publicity thing to have it posted in all the papers, twin 22 kW charging points which most electric car owners can only draw 7 kW in fact some have only a 3.5 kW 16 amp charge point, the Renault Kango from 2011 to 2018 was only 3.5 kW, the latest model does now charge at 7 kW but no DC charging, however it means people who had the early models did not really need any current transformer or other methods to ensure it did not draw too much power, and with the Renault Kango example they went from type 1 to type 2 charging point well before they raised the charge rate.

So we have a legacy of older charging points which are likely not to modern spec. And also likely not fitted by people specially trained to understand the safety problems associated with the charge points. As with other changes the problems are swept under the carpet until some thing goes wrong, then as with the thermal plastic heater tanks used with domestic hot water, suddenly it is realised we haves 1000's of homes with a potential danger.

 

[ScottishGasMan]

Not a clue as to rules in Scotland, however my understanding is to get government grants you need to have it installed by some one who has done the courses on EV installations and can sign the forms.

I'm not looking for any grant money, most the prices I've seen are including the grant money are inflated way above there being any point in it in the first place. And to a degree I understand that with the hoops they need to jump through to be allowed to fit units for grant work.

As far as it goes up here. As far as I'm currently aware, the electrician sends off a form to the DNO, depending on the installation either beforehand to request permission or afterwards to inform them that the new load is on the network, as I say depending on the existing supply and what's being fitted.

From there, the DNO either says ok, or they may inspect and upgrade what is required locally, if your asking permission, or they will just acknowledge that the new unit is fitted.

The charger I'm looking at the myenergy zappi, is popular, in part because it doesnt need earth rods and the likes. It's essentially wiring a single point radial circuit, and nothing too much more taxing than that.



It's like the heat pumps, same form needs filled in to advise/request connection, but to get the grant money, you need to be MCS registered, which costs so much, and comes with such a heavy paperwork burden, that many installers choose not to go down the route of accessing grant money, as essentially it doesnt ensure the job is done well, or in some cases even remotely correctly.