Car charge point testing

[goasis]

Hi,
To those who are already installing EV charge points, do you test as you would any other radial circuit, or do you have a specific EV point tester or EVSE adaptor for your MFT? what additional testing do these provide, and is using them in order to meet manufacturers instructions as I don't think there is anything specific in BS7671 about testing? (its in the van right now and its to cold to go outside and get it!!)

 

[timhoward]

Good question! I think you are correct that there is nothing specific about testing EV points in BS7671 including amendment 1.
But as the EV charging point device itself can contain safety critical features such as an RCD, PEN fault interruption, or current limiting, and as we are usually relying on these features to comply with the regs to my thinking it's necessary to perform testing at the output of the charger and check all these things do what they are supposed to do.
The adaptors let you simulate various capacity leads, pretend to be a car in various charging states, and trigger control protocol faults and earthing faults. You can also connect a load though it and check a CT clamp is working if the device is set to adapt to the max demand.
I don't do a lot of this stuff, and don't own an adapter. I'm lucky enough to be able to borrow one as and when needed. The resident expert is @Gavin John Hyde .

 

[Gavin John Hyde]

When testing an ev charger there are no specified tests in GN3 beyond those for standard circuits but the catch all is manufacturers instructions and functional testing.
So the use of a test adaptor to simulate the various charge states is required in my view as you can check the operation of the software, activate the contactor amongst other things. it covers the functional testing requirement.
It can also be good to verify the CT clamp is working - especially if extended over a long distance as they are calibrated to a set parameter and distance can affect this (especially the Andersen A2 if going over 30 metres!) For example the Andersen installer menus (Andersen will provide the codes to access if approved) will show you the CT readings and verify it. for other chargers I will sometimes temporarily set the grid limit very low and then put all the loads on to see if charger stops. with most installs this isn't required but only those with long cable runs to the main incomer.
I also use a Wi-Fi analyser tool and record the Wi-Fi signal strength so I can show the charger is within reach, you would be amazed how many customers call to ask why the charger isn't connected to the Wi-Fi in bad weather!!
some charger manufacturers have specific requirements - IE EO ask you to check wifi before fixing the charger to the wall,
RCD testing is a good thing done through the adaptor - especially to test the 6mA DC protection inside as testing at the terminals inside wont test this,
If fault finding a charger that wont charge (especially on old units with old cables/outlets then you can do continuity testing on the CP link on each end of the tethered cable or CP pin to wire inside. its only 0.5mm CSA so very thin but have come across lots of leads that have been twisted, damaged run over etc, The CP link is vital in the handshake process to get the charger and car synced and charging correctly.
Of late there has been quite a few cases of Teslas not charging when the plug is inserted, Tesla changed the tolerances ever so slightly that the plug doesnt align, we are talking mm at most here, you literally have to force the plug into the car. charger works fine just a connection issue

 

[goasis]

Wow, super detail reply, thank you for taking the time.
I've been on the course (total waste of a day, poor instructor, but that's another story) and read the guidance note, but only just started thinking about this additional testing, (Not mentioned at the aforementioned course) as have been asked to quite to install one. But in reality, for a one off instal the costs of the test equipment are prohibitive really, although the potential for more of this kind of work to come along is pretty big I guess. How many jobs do you turn down before you make the investment and add another string to your bow?!

 

[timhoward]

If you are feeling enterprising, you could make your own?!

 

[goasis]

Haha!! Nice idea, perhaps not though!!

 

[timhoward]

Haha!! Nice idea, perhaps not though!!

I think I won't sleep properly until I've tried this out...

GitHub - pulsatrix-emobility/CP-PP-miniEVsimulator: A small PBC to simulate the CP and PP signals of an electric vehicle (EV)

A small PBC to simulate the CP and PP signals of an electric vehicle (EV) - pulsatrix-emobility/CP-PP-miniEVsimulator

github.com

I'm getting a batch of PCBs made. It's utterly insane that you have to pay £600 for that simple circuit.

 

[goasis]

let me know if its successful! I'll buy one!

 

[Gavin John Hyde]

I think I won't sleep properly until I've tried this out...

GitHub - pulsatrix-emobility/CP-PP-miniEVsimulator: A small PBC to simulate the CP and PP signals of an electric vehicle (EV)

A small PBC to simulate the CP and PP signals of an electric vehicle (EV) - pulsatrix-emobility/CP-PP-miniEVsimulator

github.com

I'm getting a batch of PCBs made. It's utterly insane that you have to pay £600 for that simple circuit.

I agree, It is in essence a bunch of resistors which simulate different functions / charge states along the CP link... I do think its only a matter of time before somebody makes a cheap version

 

[timhoward]

I agree, It is in essence a bunch of resistors which simulate different functions / charge states along the CP link... I do think its only a matter of time before somebody makes a cheap version

The most expensive component seems to be the Type 2 plug. I can get 5 PCB's made and shipped for under $10.