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In photovoltaic systems, errors may occur caused by problems on the grid side.
Inverters are very sensitive to grid problems and respond quickly. Among them, grid imbalance faults, although rare, can easily affect inverters.
In this article, we will share information about “grid imbalance” or G-PHASE errors that appear in photovoltaic systems and their solutions.
Fault description
At startup, the Solis inverter will detect the grid status. If the grid phases are unbalanced, the inverter will disconnect from the grid and display the “G-PHASE” error.
Causes of “G-PHASE” errors
1. Voltage imbalance on the grid side
Unbalanced grid is an important issue that causes this alarm for the inverter as the inverter monitors the grid voltage in real time. When the grid three-phase waveform is abnormal, the inverter will give an immediate response and disconnect from the grid.
2. Large-scale equipment is in use, which impacts the network and makes the network unstable
For PV systems installed in industrial areas, inverters are more prone to grid alarms such as grid overvoltage, grid unbalance and grid imbalance. All this because the operation of large equipment causes voltage disturbances in the network, which in turn affect the inverters.
Solution: Use an oscilloscope to check whether the three-phase voltage and grid waveform are normal. Otherwise, record the waveform and report it to your local Solis technical team for technical support.
Possible causes related to the inverter
1. The AC cord is incorrectly connected
During the installation process, errors can be caused by cables that are incorrectly connected, which causes phase imbalance in the power injection process.
Solution: Reconnect the AC cord and verify that the wire sequence is correct.
2. The AC wire used in the photovoltaic system is unsuitable
If an inappropriate cable is selected during the design process, such as a bad AC cable made of low-quality material or with a small diameter, it can cause problems.
The system will be in contact with the metal of the cable due to the heating effect of the current during long-term operation of the system. The film is deformed and darkened, and the impedance is significantly different, which will make the three-phase voltage appear unbalanced and cause the inverter to alarm.
Solution: For correct cable selection and specifications, refer to the manual supplied with your Solis inverter, which contains detailed cable recommendations.
3. The AC terminal of the inverter has poor contact
If there is a problem with the AC terminal of the inverter, such as loose cable, poor cable contact, etc., this alarm will also appear.
Our suggestion is to replace the AC terminal of the inverter. Your local Solis service team can provide support and advice on this.
Summary
The G-PHASE error is an uncommon type of problem, but it can cause the system to shut down and affect power generation.
Therefore, when this fault occurs in a solar PV system, it needs to be corrected in time to minimize system downtime. Follow the solutions provided and, if necessary, utilize the assistance of your local Solis support team to restore the system to normal operating conditions.
The opinions and information presented are those of the author and do not necessarily reflect the opinion of Canal Solar.
