Reducing charging current intensity using control display

[Gazza]

Has anyone out in i3 land been able to successfully reduce the charge amps the car will draw from their installed home charger. The BMW supplied charger will adjust downwards just fine to confirm it can be done. My problem is the Clipper Creek 16 amp charger which I now wish to use with off grid solar charging appears to not respond to changing the charge setting with the idrive controller. The i3 owners handbook suggests for 15 amp charging the availability of drawing a reduced 11.25 amp or a low 7.5 amp setting, depending on the relevant market.

Any suggestions or experiences out there.???

Cheers.

 

[jadnashuanh]

The steps down from maximum are based on whether the EVSE is run off of 120 or 240vac. The goal is to ensure that you don't overload the circuit in case that something else is on that supply line drawing current.

If a lower maximum is required, it might be possible to adjust the EVSE itself to announce it has less capability, and the car will not ever try to draw more than that. That would require opening up the EVSE, and that might not be straightforward and may void any warranty available. The pilot signal is what announces the maximum available. Normally, the car will ask for the most available, unless the setup menu has been tweaked to say use less, but those steps are not adjustable.

 

[Gazza]

Thanks Jim. Here in Australia it's 240v. I see Clipper Creek now have a 12 amp international model which may be an alternative to sizing upwards the solar. With some of the EVSE aftermarket offering adjustable amp settings (ChargeAmps and their compact Sparky model being one) it's a pity there is not a type of separate inline regulator box that would plug in to the GPO and do the same function of stepping down the amps.

Regards.

 

[jadnashuanh]

If the pilot signal were a simple voltage level, an inline adjuster wouldn't be hard to make. But, the signal is a pulse width modulated square wave...the duty cycle determines how much power is available from the EVSE. https://code.google.com/p/open-evse/wiki/J1772Basics shows the concept.