Lower voltage power supply: 120V AC or 150V AC

150V AC at 6A is about the “right speed” for solar-charging my 24 kWh e-NV200 from my small rooftop PV array – at least in late summer – and I am routinely doing this with a bog-standard 6A IC-CPD that is supplied from a 3:2 autotransformer… see below. However: the E-series is rated for operation only at a supply of “220 - 240 VAC”, and my PV array rarely produces the 1.5 kW of power that’s required to solar-charge an EV at 6A 230V AC, so the E-series (in its current design) offers only some safety features but would rarely (if ever) allow any solar-charging of my EV.

Accordingly… please consider rating an E-series model for a wider range of supply voltages. For simplicity and safety I’d guess you’d want to absolutely forbid a change in supply voltages when the unit is powered… but in the long run, ideally, the supply voltage might be lowered whenever the 6A minimum-charge rate of an EV would over-run the excess solar power available at the household, and it might be raised whenever the maximum charge rate of the E-series installation (e.g. 16A) is too small to deliver a charge at the maximum rate accepted by the EV’s charging circuit, and the customer has put their E-series into a “charge now at maximum rate” mode (rather than in a “charge only when solar power is available” mode, or in a “charge only at night-time rates or when solar power is available” mode).

Hi there, and sorry for the late reply as we’d missed this one.

This is an interesting use case, and not one we’ve seen before in regards to someone charging their vehicle at such a low voltage.
It’s good to see this is working for you, but in practice, we’d have concerns about adjusting the rating of our products to a level that is so far out of the nominal operating voltage range for most EVs.

Our products are designed first and foremost to perform optimally for the most common use cases, and because of this our products do enter an under-voltage fault condition when the mains voltage drops below 190V. In the context of the NZ and Australian grid, this would represent a serious brownout condition and we would not generally recommend that our customers charge below this level.

Sorry we can’t be of more help in this instance, and thank you for your interest in our products.

Hi, thanks for taking the time to reply.

I do take your point: if you’re designing your products solely for use in NZ and Australia, then you wouldn’t want to mess around with design & test of a Mode-3 EVSE for operation at the range of voltages of the world’s grids. And… even a Mode-2 IC-CPD might best be designed with multiple models, so that it can handle brownouts more gracefully and safely!

I’ll continue to hope that someone will soon design & market a Mode-4 EVSE which will be “solar-smart” down to 1000W (or perhaps even to 600W) and up to either 3 kW (or to 6 kW to cover a somewhat wider range of household PV inverters).


No worries Clark. As you’re probably aware, the IEC 61851 spec prohibits charging at less than 6A. Presumably, this is because charging most vehicles at a rate less than that becomes relatively inefficient. I’d be a bit uncertain about varying voltage dynamically during a charge, as it could cause some unintended side effects with different vehicles, even if the EVSE was designed to support it. The reality is, if an EVSE manufacturer designs something that ‘can’ operate outside of the spec, they will no doubt bear the support burden of when things inevitably go wrong! :grimacing:

All the best,

Hi Ed, you’re right, it may be dangerous to vary the AC-charging voltage by more than 10% during a charge. I never do this. So : a “solar-smart” AC charger would have to fix its voltage at the start of each charging session. I guess it might be possible to close down an IEC 61851 charging session and then open another with a different charging voltage… but even if this is specifically allowed in the spec, then you’d have to see a big market to take the risk of supplying equipment which does this.

However … I believe it is possible for a DC fast-charger to vary the amperage it supplies? If not, then that’s greatly limiting its ability to “help” a lines company shed load in order to avert a brownout, or rather, it’s raising the stakes for load-shedding because the only choices are to completely terminate the DC fast-charge session or to continue it at whatever amperage rate the EV is requesting. Anyway that’s my hope: that there’ll someday be DC chargers that are both affordable (so perhaps limited to 6 kW or even 3 kW) and “solar-smart” (so can supply as low as the 600W that is the nominal power of the minimum 6A 100V AC charge allowed – and routinely used, in Japan – on an AC charging session).