Although the photovoltaic inverter has a long life, it will always "get sick" more or less in the process of generating electricity. Will you "treat" your photovoltaic power station? If not, take a look at the following.
The inverter screen is not displayed
Fault analysis: No dc input, the inverter LCD is powered by dc.
(1) The component voltage is insufficient. The working voltage of the inverter is 100V to 500V. When it is below 100V, the inverter will not work. Component voltage is related to solar irradiance.
(2) PV input terminals are connected with each other inversely. PV terminals have positive and negative poles, which should correspond to each other.
(3) The dc switch is not closed.
(4) When the components are connected in series, one of the joints is not well connected.
(5) One component is short-circuited, causing other groups to fail to work.
Solution: Measure the dc input voltage of the inverter using the voltmeter. When the voltage is normal, the total voltage is the sum of the voltage of each component. If there is no voltage, check whether the dc switch, terminal, cable connector, component etc. are normal. If you have multiple components, separate access tests. If the inverter is used for a period of time and no reason is found, it is the hardware circuit fault of the inverter. You can contact the manufacturer after sale.
The inverter is not connected to the network, and the screen shows that the power is not connected
Failure: The inverter is not connected to the network, the screen shows that the power is not connected
Fault analysis: The inverter is not connected to the grid
(1) The ac switch is not closed.
(2) The ac output terminal of the inverter is not connected.
(3) During wiring, the upper end of the output terminal of the inverter is loosened.
Solution: Measure the AC output voltage of the inverter with a multimeter voltage file. Under normal circumstances, the output terminal should have 220V or 380V voltage. If there is no, check the connection terminals to be loose in turn, whether the AC switch is closed, or whether the leakage protection switch is broken.
The screen shows high PV voltage
Fault analysis: High dc voltage alarm
Possible reason: The number of component series is too large, causing the voltage to exceed the voltage of the inverter.
Solution: Because of the component\'s temperature characteristics, the lower the temperature, the higher the voltage. The input voltage range of single-phase serial inverter is 100-500v, and it is recommended that the voltage after the group is between 350-400v, the input voltage range of three-phase series inverter is 250-800v, and the recommended voltage after the group is between 600-650v. In this voltage range, the inverter has high efficiency and can generate power when the irradiance is low in the morning and evening.
The screen shows low PV insulation resistance
Fault analysis: The ground insulation resistance of pv system is less than 2 megohm
Possible causes: Solar modules, junction boxes, dc cables, inverters, ac cables, terminals and other places have wire to ground short circuit or insulation layer damage. PV terminal and ac connection shell are loose, resulting in water inlet.
Solution: Disconnect the power grid, inverter, check the resistance of each component wire to ground, find out the problem point, and replace it.
The screen shows the output leakage flowing high
Fault analysis: The leakage current is too large
Solution: remove the input end of the PV array and check the peripheral AC grid. The dc end and the ac end are all disconnected, and the inverter will be out of power for more than 30 minutes. If it can be recovered, it will continue to be used. If not, contact the after-sales technical engineer.
The screen shows an overrange of the city voltage
Fault analysis: The power grid voltage is too high. The resistance of power grid increases, so the user side of photovoltaic power generation cannot digest it, and when it is transported out, the voltage of the output side of the inverter is too high, causing the inverter to shut down or reduce the amount of operation.
(1) increase the output cable, because the thicker the cable, the lower the impedance.
(2) the inverter is close to the junction point, and the shorter the cable, the lower the impedance.