How to charge slower than 6A

[4est (Dan Padure)]

I’m trying to charge slower than 6A
I changed MIN_CURRENT_CAPACITY_J1772 to 5

Now I see Pilot at 5A, but Current Now is still at 6A

Am I missing something?

Thanks

[Gwil]

Charging below 6A is not supported by the official firmware. There are a few threads on here about this:

EVSE Signal less than 6A?

Heya! I have used some time now to test the emonEVSE, and I must say, I like it a lot! I have a victron off-grid system that I use, and on cloudy days I have to turn charger on and off every hour or so when solar is providing less than 6A. I read the standard starts at 6A, but I also see some people claim that it is possible that some cars can charge at a slower rate if the EVSE signals that. Is this true, and is that something that could be implemented?

[glyn.hudson]

The limitation is the vehicle, 6A is the lowest charging rate that J1772 supports.

[4est (Dan Padure)]

the vehicle it’s a Tesla and it supposed to charge at 5A, you can do this from inside the car
isn’t the J1772 analogic, why wouldn’t duty cycle of 5A work?

[Stu_A]

Hi, I understand J1772 specifies only 1A steps for pilot signal from 6A upwards. Sure the car may be instructed to draw less power via some internal software, but not via the J1772 pilot signal.

I suspect most cars have a very crude pwm detector that is incapable of distinguishing small pwm steps as it is not required to comply. Indeed it seems my Nissan Leaf fails to turn on below 8A pilot… And then it consumes 5.5A!

[glyn.hudson]

@Stu_A

Indeed it seems my Nissan Leaf fails to turn on below 8A pilot… And then it consumes 5.5A!

Interesting. What model year Leaf do you have? My 2014 UK built model has no issues charging at 6A, although efficiency is reduced:

I agree, as far as I understand J1772 pilot is limited to 1A increments.

[Stu_A]

I have mk2 Leaf, 68 plate, 40kWh battery & 6kW onboard charger. It seems to charge ok, just does not respond to the pilot value shown on the UI as I expected. I did wonder if something was causing the pilot pwm to be detected incorrectly, maybe a bad cable connection or a slew rate issue. Have not had a chance to connect another vehicle to see if it’s the EVSE unit or my car . I must ask someone to come over and try it…