Based on the current documentation and real-life experience, the current 'Force Charge' mode logic limit grid import to the inverter capacity, i.e. maximum grid import is 8kW for the KH8 inverter. In the scenario where the PV is generating 1kW, the house load is 6kW, and when the inverter is Force Charge mode, it would only charge the battery at 3kW. The maths here is 8kW (grid) + 1kW (PV) = 6kW (load) + 3kW (battery charging).
The 'Force Charge' mode logic should not limit the grid import to the inverter rated capacity to supply the load and charge the battery at maximum inverter capacity. The maths should be 13kW (grid) + 1kW (PV) = 6kW (load) + 8kW (battery charging at maximum rated inverter capacity).
You might want to check your Import settings on your are high enough on your Inverter
KH7 here for reference (Import set to 18400W, 80Amp grid fuse x 230V)
KH7 here for reference (Import set to 18400W, 80Amp grid fuse x 230V)
My grid fuse is 80A and import limit set to 16.5kW.
This issue definitely exists with KH Firmware 1.69 and 1.70, this wasn't the case on Master firmware 1.67.
I have an 80amp main service fuse and 80Amp main circuit breaker. My KH10 inverter is connected to a 63amp circuit breaker (Australia inverter limit). The inverter has set 80amp current import/export limit, and 20kw power import/export limit.
When on version 1.67 Master Firmware I could grid import 17+kw from grid (as per attached screenshot have many more examples), 10kw would go to battery (battery charges at 11kw due to dc coupled system allowing 1kw more from solar) and remainder would cover house loads of 7kw plus (In this case 1kw of house load was covered by solar). So in this example 17.33kw Grid Import+2.01kw solar Generation= 11kw battery charge+8.34kw house load.
From version 1.69/1.70 (Tested both) Master Firmware KH Inverter the max I can grid import is approx. 14.7kw or 63amps. The KH10 inverter has current limits set to 80Amp Grid Import/Grid Export limit, 20kw Grid import/Grid export Power. (As per attached screen shot) Grid import maxes out at 14.7kw however not above 17kw as in 1.67 firmware. 14.7kw+6.49kwsolar (21.2kw)=15.1kw house load+6.13kw battery(21.2kw total). If I was on version 1.67 during this example this formula would be more like 15.1house load+11kw battery charge (25.1kw total) = 6.49solar+18.6kw Grid import (25.1kw total)
I have raised multiple service desk tickets, but FOXESS Australia R &D/Support don't understand the difference between Grid Import and Inverter Maximum AC Current.
I would suggest raising this ticket with your countries support and hope you get a member of staff who understands this so it can be updated on a version of firmware greater than 1.70 for the KH series of inverters. This problem is affecting the KH series of inverters in Australia and UK as people from both countries are reporting this issue that I am aware of, I suspect other countries who have this model would be having the exact same problems.
I have an 80amp main service fuse and 80Amp main circuit breaker. My KH10 inverter is connected to a 63amp circuit breaker (Australia inverter limit). The inverter has set 80amp current import/export limit, and 20kw power import/export limit.
When on version 1.67 Master Firmware I could grid import 17+kw from grid (as per attached screenshot have many more examples), 10kw would go to battery (battery charges at 11kw due to dc coupled system allowing 1kw more from solar) and remainder would cover house loads of 7kw plus (In this case 1kw of house load was covered by solar). So in this example 17.33kw Grid Import+2.01kw solar Generation= 11kw battery charge+8.34kw house load.
From version 1.69/1.70 (Tested both) Master Firmware KH Inverter the max I can grid import is approx. 14.7kw or 63amps. The KH10 inverter has current limits set to 80Amp Grid Import/Grid Export limit, 20kw Grid import/Grid export Power. (As per attached screen shot) Grid import maxes out at 14.7kw however not above 17kw as in 1.67 firmware. 14.7kw+6.49kwsolar (21.2kw)=15.1kw house load+6.13kw battery(21.2kw total). If I was on version 1.67 during this example this formula would be more like 15.1house load+11kw battery charge (25.1kw total) = 6.49solar+18.6kw Grid import (25.1kw total)
I have raised multiple service desk tickets, but FOXESS Australia R &D/Support don't understand the difference between Grid Import and Inverter Maximum AC Current.
I would suggest raising this ticket with your countries support and hope you get a member of staff who understands this so it can be updated on a version of firmware greater than 1.70 for the KH series of inverters. This problem is affecting the KH series of inverters in Australia and UK as people from both countries are reporting this issue that I am aware of, I suspect other countries who have this model would be having the exact same problems.
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