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nathan-skelly asked

EVCS NS Off Grid - Won't Charge in Auto Mode

Hi There,

I've got a new off grid setup that utilises 3 x redflow batteries and approx 10kw of solar, running a Cerbo GX, MPPT 450/200, Multiplus inverter, with an EVCS NS. The batteries are wired on the DC bus.

I've been struggling to get the EV station to work in auto mode. For a while I couldn't get it to choose auto, I finally managed to get that setup, but now I can-not charge my car regardless.

I set the minimum SOC as 40% to try and get it to work, but even in manual mode, with more than 40% charge, it says the SOC is too low. This seems to be regardless of having solar or not.

When I look through the manual, I believe there is an option to say it off grid, however I cannot see that anywhere?

Any suggestions?

offgridev charging stationev charger nsevsc
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nathan-skelly answered ·

Hi There,

I've gotten further with it, but still can-not get it to charge automatically.

As I sit here typing this, My battery is 76% and has stopped charging, my EVCS is set to charge at an SOC >70%, but won't do it automatically, it just says 'Waiting for sun'

If I switch to manual, I can charge the car, and see my PV generation step up as well.

I'm sure I'm missing something obvious, but I can't tell what.

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ktouart answered ·

I can confirm the same issue for me, the reason I believe it's due to incorrect estimation of actual p.v. power available. To "force start" I manage a dirty and absurd workaround: firing up a load large enough, let's say a resistive heater for few minutes, than drop it. At that point hitting start makes the EVC starting and than adapting the power rate following the p.v. production.

Having a damn "forse start" or "start charging now" button would be a godsend since p.v. estimated production is always an estimation, often a false one.

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nathan-skelly avatar image nathan-skelly commented ·
I never got it working consistently, it would seem my main issue was old firmware, which I corrected. It still didn't quite do what I wanted it to do.


I started using Node Red to control it in recent months, it gives far more granularity in the control.

For example, at the moment I've got 3 charging schemes setup:
1. Charge overnight if predicted solar is high enough to charge the home battery the next day

2. Charge when home battery is charging <85%, trying to use excess solar but still charge home battery

3. Charge when home battery >85%, try to us all solar available and have the battery at 0 charge.

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