As the “heart” of photovoltaic power generation, the health of the inverter is closely related to the smooth operation of the photovoltaic power generation system. Understand common inverter alarms, accurately determine the cause of inverter alarms, and be the “family doctor” of your own inverter, so that the inverter can run smoothly.——GROWATT INVERTER
- The inverter alarm screen or APP displays “Warning 103 or Warning 105” not caused by internal devices, indicating that the reading and writing of the EEPROM has failed. Generally, restarting the inverter can be repaired. If the screen or APP displays “Warning 100 or Warning 400”, it means that the fan is alarming. First, check whether the fan is stuck by foreign objects, then manually stir the fan in the power-off state, and restart the inverter. It is recommended that the inverter generally clean the fans once every six months.
- Inverter alarms caused by common external environments
- The LCD displays “No AC Connection”. This type of alarm means “no mains connection”, generally appearing in single-phase inverters, indicating that the mains is not connected or the AC circuit breaker is disconnected. When such an alarm occurs, check whether the AC side line connection is good and whether the AC switch is closed.
- LCD displays “Overtemperature”. This type of alarm indicates “inverter overtemperature”. Usually, the place where the inverter is installed has insufficient ventilation, the inverter is exposed to the sun, and the inverter fan is abnormal. To solve this problem, it is first necessary to ensure that the inverter installation site is ventilated to prevent the inverter from being exposed to the sun. For the abnormal problem of the fan, it is necessary to check whether the NTC line and the NTC temperature sampling circuit are well connected.
- The LCD displays “PV Isolation Low”. This type of alarm means “insulation resistance is too low”, which may be caused by the influence of panel insulation, cable insulation, grounding reliability of component support, installation temperature and humidity.
To check this abnormality, first disconnect the AC/DC air circuit breaker, use a special MC4 dismantling wrench to remove the positive and negative poles of the DC measurement string, then use the multimeter megohm gear, the red test lead is connected to the positive pole of the string, the black test lead is grounded, and read The measured positive-to-ground impedance reading of each channel, and then connect the red test lead to the negative pole of the string, and read each negative-to-ground impedance reading one by one. If it is greater than 50kΩ, the inverter judges that the insulation of the string is reliable, less than or equal to 50kΩ, Then the inverter judges that there is a problem with the insulation of the string, the inverter will automatically protect and stop working and report “Insulation resistance is too low”.
- The inverter screen is not displayed. The inverter does not display because the LCD has no DC input or the auxiliary power supply is abnormal. At this time, it is necessary to measure the DC input voltage of the inverter with the voltage range of a multimeter. The total voltage is the sum of the voltages of each component, and the voltage problem is ruled out. After eliminating the voltage problem, check whether the DC switch, wiring terminals, cable connectors, components, etc. are normal.