Hi ,
I have had the above equipment installed for a month. Its retro fitted as ac coupled because I have an existing solar panel installation with 2.4 wp solar panel and a 2kw Solis inverter, operating under the FIT tariff. The fox equipment is installed on a separate circuit between the house consumer unit and the house meter, controlled with a ct clamp on the main house load. There's no second ct clamp monitoring the existing solis inverter. its been left on self use since installation.
I'm experiencing multiple issues including the fox system importing from grid when there's lots of battery power available - for hours albeit at c 200 - 500w, exporting to the grid when the battery is low on charge for hours, and also apparently going completely haywire discharging the battery at 6kw exporting 2-3kw to the grid and seemingly inventing house loads. These are all apparent and recorded on the v2 web app analysis graph. Its does operate relatively normally as well !
I have occasionally tried to correct its errant behaviour using the work mode schedule for forced charge and discharge but it generally just ignores the schedule. Its had its firmware updated by fox support twice, doesnt seem to fix anything.
Has anyone else this style of installation, where the system either operates correctly or incorrectly? Any ideas/feedback gratefully received.
If you have no second CT clamp fitted the Fox inverter cannot calculate the load or grid metrics correctly because it has no way of knowing what the Solis inverter is outputting - the net result is that it should work correctly but your home consumption stats won't be accurate.
Hi Dave thanks for replying.
Yes the fox inverter can only see the net energy flow, I'm not really concerned about seeing the house consumption. As an example on the 15/06 at 19:50 the battery soc was 79%, the battery was discharging to meet the house draw of c 450w, but at 19:55 the inverter switched to grid import, and remained doing that until 04:40 on the 16th (importing c 3kwh ) when it chose to switch back to battery discharge, this is backed up by my smart meter 30min readings which I have up to midnight on the 15th, so its a true reading not a measurement mix up. Also obviously the solis inverter was producing nothing over this time. If there was a ct2 clamp in place would the grid import not have happened?
Yes the fox inverter can only see the net energy flow, I'm not really concerned about seeing the house consumption. As an example on the 15/06 at 19:50 the battery soc was 79%, the battery was discharging to meet the house draw of c 450w, but at 19:55 the inverter switched to grid import, and remained doing that until 04:40 on the 16th (importing c 3kwh ) when it chose to switch back to battery discharge, this is backed up by my smart meter 30min readings which I have up to midnight on the 15th, so its a true reading not a measurement mix up. Also obviously the solis inverter was producing nothing over this time. If there was a ct2 clamp in place would the grid import not have happened?
From what you have said it's possible that the primary CT clamp has been positioned incorrectly (or wrong way round) - 19.55 sounds approx where the Solis might stop net exporting, and 04.40 where it starts exporting again - you wouldn't expect the inverter to be charging the batteries if there is no excess solar unless you have force charge schedules set up ?
To confirm it's operation it would be helpful if you could post a couple of screenshots from the app please, the first is the entry page which shows the house and power flows, then if you click on Daily Production, select a full day and screen shot the bottom Statistics graph (ideally for a few days)
To confirm it's operation it would be helpful if you could post a couple of screenshots from the app please, the first is the entry page which shows the house and power flows, then if you click on Daily Production, select a full day and screen shot the bottom Statistics graph (ideally for a few days)
The example was showing the fox inverter choosing to grid import rather than use the battery
heres my dashboard
and the analysis from 15/06
heres my dashboard
and the analysis from 15/06
The lower graph appears correct given it isn't measuring the load correctly because of the other inverter, albeit at 8pm the battery shuts off and it reverts to using the grid.
The large spikes of grid import you will see regardless as the inverter couldn't supply that much power, but the fact that it's not trying suggests some kind of scheduling or system min soc issue.
What are your minsoc, system minsoc set to, and do you have any schedules configured (or VPP connection such as Octopus / Agile that could be remotely controlling).
The large spikes of grid import you will see regardless as the inverter couldn't supply that much power, but the fact that it's not trying suggests some kind of scheduling or system min soc issue.
What are your minsoc, system minsoc set to, and do you have any schedules configured (or VPP connection such as Octopus / Agile that could be remotely controlling).
The min soc and system min soc are set to 10%, max is 100%, the default I think. I'm on an octopus normal fixed tariff, not the time of use tariffs, and I don't have any vpp agreements. I haven't put any tariff info into the system.
Dave, its just flipped over to grid export instead of charging the battery. it was charging, then a larger house load kicked in which the battery supplied, then when that load finished it started exporting the excess to the grid, its been doing this for the last 25 mins
I think the problem could be related to your second inverter and the CT sensing of the Fox inverter (i.e. it is getting confused when the load is going from negative > positive or back again) , this unfortunately is an installer only setting but he can change it remotely, can you ask them to make sure that automatic meter reverse connection sensing is disabled.
ok i've sent that suggestion to them, fingers crossed.
Dave , the installer can't find that setting, could you point us to where it can be found?Dave Foster wrote: ↑Wed Jun 17, 2026 2:32 pm I think the problem could be related to your second inverter and the CT sensing of the Fox inverter (i.e. it is getting confused when the load is going from negative > positive or back again) , this unfortunately is an installer only setting but he can change it remotely, can you ask them to make sure that automatic meter reverse connection sensing is disabled.
It has to be viewed with installer or agent access, it is the last item in the advanced menu list
And when you select that item you will see
CT1\Meter1ReverseEnable should be disabled
Can't see an advanced menu, I've gone settings-feature-meter/CT, then it's set or check?, set gives me a screen with CT on it, do I enter that?
Note this is on the inverter control panel
Note this is on the inverter control panel
You cannot access that menu through the inverter panel, it has to be done via the app or website whilst using installer or agent access.