EV Charger Replacement and Wiring

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Hi all, new around here so go easy please

Got a situation where I can’t get a definite answer.

I currently have an old 7kw 30A Chargemaster, which I want to replace with a new Easee One 7.4Kw 32A charger.
The way my install is, the consumer unit is under my stairs in the middle of the house, and 6mm twin and earth (2x6 +2.5) was used and all signed off, and tbh, have never had any issues.
The cable is chased into the wall slightly, then drops under the floor and is clipped along, to the front of the house, where it then is chased up the wall slightly, and out into a junction box.
From the Junction box, I’m assuming they have used SWA cable for that short run upto the charger.

I want to get my electrician to replace the unit, which he said would be an easy swap, as the cable is capable of carrying 47A and there is minimal loss as the cable is not insulted in walls or conduit.
He did say he would change the MCB to a 40A as the current 32A would not be sufficient enough.
Now just to check and be sure, I’ve spoke to a few other EV installers, who some agree with what my electrician is saying, but then others are saying that the earth has to be the same size cross section as the twin wires?
I clearly don’t have this, as it’s 2x6mm + 2.5mm.
Some saying I need to rewire, which I’m trying to avoid, and others saying, that I’ll be totally fine with the current cable.
I’ve been told SWA etc is not necessary as none is exposed or buried underground but is clipped under the floor.
My current charger is a “dumb” one, so am replacing with a smart one.
The Easee One, has built in RCD and PEN and has its own built in power monitoring without the need for extra wires back to the consumer unit.

Can someone please help shed some light please.
I’m also in the UK if that helps.

TIA
 
First things first could you post a photo showing your consumer unit / fuse board?

6mm twin and earth is fine in about 90% of cases

SWA probably isn’t necessary, a lot of EV installers use hituff

Not sure why a change to the MCB has been suggested
 
Easee is a poor choice as they were banned in Sweden and their native Norway for misleading information about RCDs. Also an expensive "Equaliser" is needed for load curtailment. Nearly every EVSE installation will require load curtailment.
 
Also, it is unlikely that the MCB needs changing.

Probably quoted as 7.4kW @ 240V which is 30.833A.

If quoted as 7.4kW @ 230V is 32.174A so it is unlikely that it would be designed as that.
 
Also, it is unlikely that the MCB needs changing.

Probably quoted as 7.4kW @ 240V which is 30.833A.

If quoted as 7.4kW @ 230V is 32.174A so it is unlikely that it would be designed as that.
32A is a poor choice of protective device as it will be running at its full rating for long durations. 40A is the correct choice, and indeed most manufacturers will state this.
 
So - what does the 32A mean, then, given that they won't trip until 36.16A is exceeded?
It's the nominal rating of the device. And it's not guaranteed to operate at 1.13 times its rating, but rather must not operate at under 1.13 times its rating, but must operate within the conventional time (typically taken as 1 hour) at 1.45 times its rating. (The area between 1.13 and 1.45 times will vary between devices.) This doesn't mean that a device operating at its nominal rating for many hours is desirable or well-designed, however.
 
Thanks for the replies.
My old charger was installed in my consumer unit with an 32A MCB with a Type AC 63A RCD on that rail.
However, my electrician will be installing a new 40A RCD consumer unit with SPD, as is now recommended to do.
But my query is the actual Twin and Earth (2x6 +2.5) that is currently there going from the consumer to the EV junction box.
Some are saying it has to be 3 core (all 6mm), but others saying the current wire I have is fine.
So basically it will be Twin + E run from consumer unit to Junction box under the EV unit, then 6mm SWA to the EV unit.

I’ve attached photos of my current fuse board, and also where my current charger is.
As I mentioned, a separate consumer unit will be installed for the new charger.

D4EFBB89-3695-41AC-B65A-AA91FE9984D1.jpeg
1f99e25c-de44-460a-8d2d-513c14308199.jpeg
IMG_8248.jpeg
1f99e25c-de44-460a-8d2d-513c14308199.jpeg
 
Anyone who says you can’t use 6mm / 2.5mm cable should be shown the door
Thing is, I just managed to find the installation manual for the Easee One, and it does state the PE cross section should be the same size or bigger than the phase wire cross section.
So it kind of confirms what some have said, although others disagree.

IMG_8277.jpeg
 
Thing is, I just managed to find the installation manual for the Easee One, and it does state the PE cross section should be the same size or bigger than the phase wire cross section.
So it kind of confirms what some have said, although others disagree.

View attachment 374339

Look at other quality EV chargers - I very much doubt they will say the same

Just looked at the Zappi unit it only mentions the L & N being 6mm

Makes me wonder if the Easee reflects Scandinavian regulations
 
Last edited:
Look at other quality EV chargers - I very much doubt they will say the same

Just looked at the Zappi unit it only mentions the L & N being 6mm

Makes me wonder if the Easee reflects Scandinavian regulations
That's exactly what it is. They're taking the Norwegian requirements as general requirements. In fairness it could be true that the terminals in their product aren't ideally suited to reduced conductor sizes.
 
That's exactly what it is. They're taking the Norwegian requirements as general requirements. In fairness it could be true that the terminals in their product aren't ideally suited to reduced conductor sizes.
Even if that is the case it shouldn't particularly matter in this instance as he says he's running swa from the jb.
 
So do you guys think it shouldn’t be a problem then using my current cable and then running the SWA from the jb?
 

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