Common faults of photovoltaic inverters
1. Low insulation impedance: Use exclusion method. Unplug all the sister strings on the input side of the inverter, and then expand them one by one. Use the inverter’s power on detection function to detect the insulation impedance and detect the inter problem group string. After finding the inter problem group string, focus on checking whether the DC connector has a water immersed short circuit support or a baking short circuit support. Additionally, you can check whether there are black spots on the edges of the component itself that cause the component to leak electricity to the grounding grid through the frame.
2. Low bus voltage: If it occurs in the morning or evening, it is considered a normal problem because the inverter is under extreme power generation conditions. If black appears during the day in Zhengluan, the detection method is based on exclusion, and the detection method is the same as item
3. Leakage fault: The root cause of this type of problem is installation quality issues, caused by selecting the wrong installation site and low-quality equipment. There are many reasons for this: low-quality direct charging connectors, low-quality components, unqualified installation height of components, low quality of grid connected equipment, or water leakage. If similar problems occur, they can be solved by spraying powder to identify the points and doing a good job in edge work. If it is the first problem with the material, only the material can be replaced
4. Direct overvoltage protection: With the pursuit of high-efficiency process improvement in the components, the power level is constantly updated and rising, and the open circuit voltage and working voltage of the components are also increasing. The design of step acid must consider the temperature coefficient issue to avoid equipment hard damage caused by overvoltage in low temperature conditions
5. The inverter should be turned on without any issues: Please ensure that the DC input line is not connected in reverse. Generally, the DC connector has a foolproof effect, but the crimping terminal has no foolproof effect. It is important to carefully read the inverter manual to ensure that the positive and negative poles are connected before crimping. The inverter is equipped with reverse short-circuit protection, and after restoring the positive Luan connection, the positive Luan starts,
6. Power grid fault: Possible occurrence of power grid overvoltage, power grid undervoltage, power grid over frequency, power grid no voltage, power grid short, etc. Therefore, check the grid connected lines and short phase circuits.