Recently I’ve installed 3 phase ESS system composed of:
3 x Mutlplus-II 5000VA
2 x MPPT 250/100
1 x Lynx Power-In
2 x Lynx Distributors
1 x CerboGX
1 x Victron Energy Meter (VM-3P75CT)
4 x Pylontech US5000
The system works as expected most of the time. The only issue I’m having is that there is a slight mismatch between PV charger output and combined AC Loads in VRM:
The discrepancy varies depending on AC Load / PV production.
When AC Load is low the difference is about 50W, but when AC Load is high the difference can reach up to 500W. Are there any ideas why it happens?
The only explanation I can come up with given my limited experience is that there is a defined inefficiency for inverting. The datasheet says that the efficiency for the 48/5000/70-50 is 96%. However, that efficiency accounts for only 259 watts. Since you have three inverters, take that 259 watts times three to get 777 and you come closer to the 610 watt discrepancy.
Thanks Jim,
I was thinking about it as well. Correct me if I’m wrong but I assume that power losses are proportional to AC Load on the line, i.e. losses per line should look as follows:
L1 = 3777 / 0.96 - 3777 = 157 W
L2 = 2017 / 0.96 - 2017 = 84 W
L3 = 70 / 0.96 - 70 = 3 W
Which is far from 610 watt I have.
I wonder if this can be related to DC busbar imbalance?
