After the start of summer, high temperature and rain weather occur frequently, which may have a certain impact on photovoltaic power plants. As the core component of the entire power station, the inverter can realize real-time monitoring of the power station operating data, timely understanding of the equipment health status, and fault warning to help lock abnormal areas. This article has sorted out some common problems and solutions, hoping to make photovoltaic power stations "fully open" in this summer.

​​​1. Is the insulation impedance to the ground too low?
Cause analysis: the weather is rainy in summer, and the casing is wet and easy to enter water; Component waterproof boxes may also fail... In the face of these problems, the most common error message is "the insulation impedance to the ground is too low."
The solution:
① Check the DC cable, component side grounding, and water inlet into the tube. Most of the panel insulation impedance problems are caused by DC cable damage, which includes the cables between components, the cables between components and the inverter, especially the cables in the corner and the cables laid in the open without pipes, which need to be carefully checked;
② Check the DC or AC bushing. If no leakage port is reserved or the casing is improperly positioned, a large amount of rainwater will accumulate in the casing, resulting in low insulation impedance of the line.
③ Photovoltaic inverter is not well grounded. If the inverter is not grounded or poorly grounded, it will affect the inverter to correctly detect the insulation impedance value of the component to the ground, resulting in a false alarm.
​2. Mains lost?
Reason analysis: Summer is a sudden storm in the blue sky, the power grid power failure occurs from time to time, and it is also one of the most common error information.
The solution:
(1) Determine whether the power grid is cut off, if the power grid is cut off, wait for the power grid to restore power supply;
② If the power supply is normal, use a multimeter to measure whether the AC output voltage is normal. First, measure the output of the inverter and check whether the output side of the inverter is faulty. If there is no problem, it is the external AC side break, need to check the air switch, tool brake, over and under voltage protector and other safety switches are damaged and broken.
​​3. Inverter LED no display?
Cause analysis: No DC input or auxiliary power supply is abnormal, DC switch is not closed, etc.
The solution:
① Use a multimeter to measure the DC voltage input of the inverter. If the total voltage is the sum of the voltages of each component, the voltage problem is excluded;
② After removing the voltage problem, check whether the DC switch, terminal, cable connector, and components are normal in turn.
​4. Is the external fan faulty?
Cause analysis: In actual operation, the inverter is mostly installed outdoors. Dust, insects, branches, and other hard objects enter the fan compartment and block the rotation. In this case, the external fan is abnormal.
The solution:
① Check the running status of the fan on site, and use tools to move the fan blades to remove foreign objects;
② Use tools such as hair dryers to blow out dust;
③ If the above reasons cannot be restored, the fan may not be able to supply power.
​5. Is the communication on the monitoring platform abnormal?
Cause analysis: The collector does not communicate with the inverter. Collector is not powered on: installation position signal problem; Internal reasons of the collector.
The solution:
① When the monitoring platform cannot monitor the status of the inverter, the operation and maintenance personnel should first determine whether the collector bound to the power station corresponds, whether the collector and the inverter are normally connected, and whether the inverter DC switch is turned on.
② Ensure that the above is normal, continue to check the collector working indicator status, if the network light is not on, it indicates that the local network signal is poor, need to install a communication extension cable;
③ If the power indicator is off, the collector is not powered on, and you can reinsert it.