Description of Settlement System
In Hungary, the time-series gross settlement system issues monthly electricity bills based on 15-minute smart meter data. The settlement is fully gross, meaning that no energy netting is applied. The imported and exported energy of each phase is measured and billed separately, without any aggregation or compensation.
Example:
R: 2 kWh import → €0.20 cost
S: 1 kWh export → €0.01 credit
T: 1 kWh export → €0.01 credit
Total payable: €0.18
Thus, the billing process is performed per phase, and the difference (net result) between phases is not taken into account.
Issue Summary
The H3-5.0-E inverter firmware cannot be configured to operate according to the required gross, per-phase behavior. Several configuration modes were tested:
Balance Load
Balance Logic First
Balance Phase Control
In all tested configurations, there are cases where the firmware attempts to balance the power of the three phases to reach a “net-zero” state.
Observed Behavior
The inverter redistributes power between phases in real time.
The system feeds energy into one phase while consuming on another, leading to double billing for the same energy.
Financial Impact
This malfunction causes direct financial loss:
The user is charged for energy that was already exported on another phase.
The inverter’s unnecessary phase balancing discharges the battery, causing energy losses and reduced efficiency.
Overall, the issue results in overbilling and battery degradation, leading to financial loss.
Expected Behavior
Each phase must operate independently, supplying or consuming energy only according to its own load.
The inverter must not transfer energy between phases or perform any internal compensation.
The firmware should implement a strict per-phase control mode compliant with the Hungarian gross settlement system, ensuring accurate billing and preventing financial losses.
I contacted Hungarian support, but the problem exceeds simple firmware settings and is beyond their ability to resolve.
Please feel free to reach out—I am willing to assist, test, and work toward a solution.