Hi, I have a 3 phase Wallbox charger, and it is set to only charge with excess solar. However it seems to stop charging even though the excess solar is still more than about 3kW? I’m with Amber and quite often the FIT is negative, so it’s annoying to be feeding in rather than charging. I’ve tried setting the minimum excess solar to 0kW and leaving blank, but it still seems to stop charging with quite high excess solar?
When using a 3 phase smart charger (eg Wallbox) the minimum charge rate is 4.1kW. This is a major disadvantage of 3 phase charging. See Single vs 3 phase when EV charging from Solar
Thanks Jay, that would explain it. Do you know why 6A is the minimum charge rate? It would seem consistent to allow 3A for example, which would mean solar charging started at just over 2kW.
When the charging power is controlled by the charger (as opposed to the vehicle) the minimum rate allowed by the EV charging standard is 6 amps per phase.
When the charging power is controlled by the vehicle there is no fundamental lower limit - it depends on the vehicle.
Some chargers support switching from 3 phase to single phase. Wallbox chargers do not support this, and neither does Charge HQ currently.
Thanks again Jay, from what I can see the standard you mention goes back to an American standard, which would mean 6A x 110V, so only a bit more than 600W. Seems a bit silly to apply the same current limit to a 3 phase 240v system, but I guess standards are like that 
. Are you aware of any move to make the standard more sensible in Australia?
I’m not aware of any proposals to reduce the minimum charge rate of EV charging, as controlled by the EVSE. The best option is to switch to single phase charging when required if possible.
It seems Wallbox do support this with their Pulsar Pro charger, but not the more common Pulsar Max. Do you have any plans to support smart phase switching in the app? Alternatively if I just configure the charger to be single phase even though it is 3 phase would that work? (Although obviously only at 7kW)
Hi again, Wallbox has confirmed the 3 phase Pulsar Max can be wired as a single phase EVSE. If I get the wiring changed to single phase and configure it in ChargeHQ as single phase will this work? Many Thanks!
Hi @davidhuck . Sorry for the epically late reply!
If you get your Wallbox wired as single phase, then Charge HQ will work correctly and will charge down to ~1.4 kW.
Once you have this done, you should unset the “Three Phase Charging” option in Charge HQ. That option only impacts the minimum amount of excess solar that is required by Charge HQ before it will start charging, because it can not automatically detect many phases will be used until charging has actually started. Once charging has started, Charge HQ detects the actual number of phases and performs its calculations accordingly.
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