What does a EV charging point actually do?

I have bought a 2nd hand Nissan leaf and have been happily charging it slowly from a 13A socket (fed by solar panels) for 6 months using the "granny lead" that comes with the car.

Yesterday, when I turned it on, the READY and CHARGE light flashed about once per second, as did the lights on the dashboard, and there was a click each time from the unit. The manual does not list this combination as indicative of anything.

This lead me to wonder what the "charging unit" actually does, It lists its input and output as 250V ac so it clearly is not a transformer/ rectifier. If it is a protective relay measuring neutral earth voltage, then maybe the ON / OFF is caused by something happening to the voltage in the house?

I have not found any information on the internet as to what is inside these units.

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  • I bet the car takes days till its fully charged on a 13amp granny lead?

    Depends on how "empty" it was to start with - not may people run the battery completely flat before re-charging. Even then at say 2.4kW (10A) a 48kWh battery can't take much longer than 20h.

      - Andy.

  • Anyway the OP says he has been charging it for 6 months (!) Joking aside, for folk who do not use a vehicle hard every day of the week, then a 13A lead may well be more than enough, as an overnight charge will be tens of kVA, and even a 100kVA battery (sporty Tesla) will only need 30 hours  or so from dead flat to full.


  • It would be interesting to see the thermal effects on that plug and socket arrangement after regular 20 hour charging periods.

  • Some ordinary 13A are known to have problems. Ones marked EV on the back should be OK. Type 2 charger manufacturers seem to aware of the problem - some units incorporate temperature monitoring into the plug, others limit the current to something well below 13A (10A is common).

    Hopefully no-one's tried plugging two of them into a double socket...

       - Andy.

  • It charges at about 10 miles per hour, so, if I drive it 20 miles, it takes 2 hours to top up, which is typical for what I do.