My ev2 charger is installed in our garage, which is about 30m away from the workshop that has the incoming mains and switchboard, as well as a solar array on the roof. It is practically impossible (sealed driveway, gardens, fruit trees, path etc, all between the house and workshop) to run a cabled CT to the incoming mains so that I can use the solar diversion charging option.
I have tinkered around with @hardbyte’s Home Assistant integration, however I have yet to be able to get a charging session to start from HA. I understand this isn’t the place to request assistance for a third party function, but if anyone else has been able to make this work, I’m all ears! I can change the maximum charge current in the charger based on my mains export, but not start a charging session.
The above notwithstanding, surely I can’t be the only person who has a solar system, but can’t connect the solar CT to their incoming mains due to distance? Is Evnex looking at other options to get around this, or is there a current solution that I am unaware of that would work?
I understand the need to make any solution work for the masses and as simply as possibly, however the omission of a way to provide the charger this information via any other means is a little frustrating, especially with the removal of support for OCPP or other officially supported API - those with a substantial HA system, or even a Shelly EM likely already have the mains import/export data at hand - I do, which makes it even more frustrating that I know exactly how much solar I’m wasting as export instead of putting into the car!
Be great to hear the thoughts of Evnex on this, or from others in the community who have ideas to solve this, or would like to see something implemented.
Thanks for reading,
George
Hi George, I’m in a similar but different situation: I’m off-grid. With offgrid systems, the CT system doesn’t work, because there is no “grid export” to detect and when the home battery is full, the PV inverter stops generating beyond the current load – if the EV charger is off, there is no extra load, so no extra PV is generated, so the EV charger doesn’t detect excess, and doesn’t turn on. Chicken and egg.
Because my home battery is far smaller than my car battery, I definitely don’t want to charge unless there is excess solar PV. It just doesn’t make sense to draw power from the house batteries into the EV.
Recently, I’ve had success with a different approach: I wrote software to get solar PV input data and battery state from my Selectronic inverter, and then control the Evnex charger via its API to adapt to the changing PV generation and loads experienced by the off-grid solar system, and use only excess power to charge the EV.
I’m a software engineer, so for me it was relatively easy to build a custom system that works more reliably and more automatically than manually setting the load control limits in Evnex’s clunky cp-link web app.
If you happen to have a Selectronic inverter, my code will probably work for you too. If not, there’s probably a way to hook something up.
It’s great that Evnex provides an API for their chargers – there are many other reasons to want to control time and rate of charge other than just PV export.
Mark
Hi Mark,
Thanks very much for the reply. It definitely sounds like you’re doing something very similar what I would like to achieve. I don’t have a Selectronic inverter, I have a 2.1Kw Enphase system and a 5Kw GoodWe system that work reasonably well together, with the Enphase system working as a slave and reducing it’s output depending on how much is being generated, to remain under the 5Kw export cap I have.
I run a Home Assistant instance that has integrations with both PV systems, as well as CT clamps in several places to understand what currents are flowing where. I did have @hardbyte 's integration installed and providing data as well, but an attempt to control the charge current last Sunday has left that dead - I can no longer access the API it would seem - need to get in touch with Evnex about that, as I can no longer access the charger using my wifi either, but mobile data works fine. I suspect I have been blocked by their servers for trying to adjust the charge current too many times.
How are you communicating with the API - are you directly polling the Evnex servers, or are you communicating with the charger directly?
The charge now toggle works again BTW, I updated the API and HACS integration. Would be good to know rate limits on the API.
I have mine set to a maximum of one call a minute, and that seems to be keeping me under the ban limit.
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