Inverter Grid Charge capped since firmware update

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Gazeruth
Posts: 2
Joined: Tue Mar 11, 2025 9:11 pm

First post so apologies for any nonsense!

I've recently had my installer update my KH7 firmware (not sure what from), but it's now showing:
Master: 1.41
Slave: 1.01
Manager: 1.39
(Also I couldn't find this on the app or web portal - I've found the battery firmware versions, but not the inverter - if anyone could point me in the direction, as ChatGPT didn't help!)

Onto the issue - before the firmware update, I used to charge my batteries and EV at the same time (Octopus Intelligent Go tariff) - and I would pull a peak of ~13.5kW from the grid while the EV and batteries charged, then usually drop to 6-7kW once the batteries had finished charging (or EV had).

Since the update, it appears that the max power I can now draw from the grid is ~7.8kW, so I'm only charging the EV, or the batteries, but not both at the same time.

Is this a setting I can tweak? It hasn't been an issue so far, but I can imagine if I'm doing a long drive, and have had a lot of drain on the batteries for a day, then the batteries won't fill up if the EV charging takes the entire "enable charge from grid" window.
KH7 7kw hybrid Inverter
4x ECS4100 (Total Capacity 15.36kw)
15x 480W Eurener Nexa Panels
Dave Foster
Posts: 1786
Joined: Thu Oct 13, 2022 7:21 pm

There has just been another firmware release for the KH Manager which is now 1.40 - Fox don't provide release notes but it's likely to be a minor bug fix.

On your batteries, can you show your current versions for Master(BCU) / Slave(BMU) so I know which version you are on, latest for ver -2 is showing as 2.003/1.14

Onto your issue, Fox have changed the firmware to allow the import and export currents to be changed - this post refers viewtopic.php?p=7054#p7054 - This is configurable by installer access only so you will need to ask either them to change the setting or email Fox service and ask them to increase your import limit (to 60A?)
Gazeruth
Posts: 2
Joined: Tue Mar 11, 2025 9:11 pm

Thanks for the reply and expertise Dave!

My batteries are currently:

Master - 1.004

Slave:
  • 1.01
  • 1.04
  • 1.04
  • 1.04
As I think I need to e-mail Fox about updating my battery firmwares - is it worth also asking them to update the limit? What's the best e-mail please? (Apologies for another daft question)
KH7 7kw hybrid Inverter
4x ECS4100 (Total Capacity 15.36kw)
15x 480W Eurener Nexa Panels
Dave Foster
Posts: 1786
Joined: Thu Oct 13, 2022 7:21 pm

That is quite old firmware so best to get it updated, the latest is a bit more temperature sensitive as Fox have rolled out a common temperature charge profile to all their inverters - Will has done a video about it.

If you email them make sure to include your inverter serial number, and to upgrade your battery firmware - if you explain you are on latest firmware which is restricting your house loads and need to change the import limit they should be able to change it for you as well. This is their address service.uk@fox-ess.com
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