Who is responsible for non compliantbev install

Hi 

Just to confirm that as Soarky Chip says my main concern about the shared rcd is 5mA from the EV plus 5mA of dc leakage from other circuits equals 10mA on the shared rcd, if its a type A it may not trip.

Given that many houses now have ev chargers  induction Hobs  air con units etc this and higher can easily occur. I am fairly sure NAPIT would recommend C2 for this.

Also it's becoming quite common practice to game the cheap energy tariff by having one car on a proper ev charger and  a second in a granny charger.

There's a more simple concern ... BS 7671 has the requirement, because an EV might have a "leakage current" around 10 mA. This doesn't leave a lot more for other equipment before a 30 mA RCD might operate in unwanted situations.

Having read the DPC of the guide to EVCPs this morning, my attention was drawn to Figure A53.2, which is new to BOB.

So the issue is not about safety at the EV because that is covered by the (assumed) RCD in the EVCP; nor is it unwanted tripping because of lack of selectivity. Instead, the risk is blinding of the (Type AC?) RCD in the CU.

I can see that one might argue that if the RCD in the CU is likely to be blinded when the EV is on charge, it may as well not be there; and if it were not present, C2 would be appropriate.

I realise that Annex A53 is informative only.

gkenyon said:

an EV might have a "leakage current" around 10 mA.

Oh, there be (small) dragons then!

531.3.2 puts a limit of 30% of the rated residual current on RCDs - so if it might exceed 9mA we can't use a 30mA RCD at all - which puts us in an awkward position with 722.531.3.101...

  - Andy.

I thought that I would have a quick shufti at some manufacturers' instructions, or at least their web sites.

Mercedes have some sort of link with Pod Point.

As the screen shot shows, they seem to be perfectly happy to protect the EVCP circuit with a type A RCD in the CU.

ETA: all right, the EV will not blind other circuits, but if its individual RCBO is blinded, what happens when the householder sticks a nail through the cable which is buried less than 50 mm below the surface of the wall?

Chris Pearson said:

ETA: all right, the EV will not blind other circuits, but if its individual RCBO is blinded, what happens when the householder sticks a nail through the cable which is buried less than 50 mm below the surface of the wall?

If they're recommending an A-type RCBO, then presumably the EVSE includes an RDC-DD which should limit any d.c. residual currents to below 6mA - so the RCBO shouldn't be blinded? (If they hadn't included an RDC-DD they they should be recommending a B-type minimum).

   - Andy.

Andy, thank you.

The datasheets for Pod Points various models say, "Protections. 6mA DC Leakage, Over current, PME and failed earth protection."

So going back to Alans original posting, the installation may or may not be compliant. Should we say an FI for the moment?

We have been told to stop using the FI code and made a decision as to the relevant code, if any.

We have been told to stop using the FI code and made a decision as to the relevant code, if any.

Ah, but the presumption has changed.

FI was a fail, so we had to say that if we did not know whether the EVCP had an RDC-DD, it was a fail; but now if we do not know, we can pass the installation and look up the datasheet later.

Odd!

We were actually told during an Amendment 4 presentation that these days we have an internet connected phone with us whilst we are preparing an EICR, so we can either find the information through the internet or contact the manufactures technical helpline to get the relevant information we require to make a decision, instead of procrastinating.