Inverters maintain residential solar systems

Maintaining the inverter is the key to ensuring the normal operation of residential solar systems. The following are the key points for maintaining the inverter in residential solar systems:

Daily maintenance

Safe operation When maintaining or repairing the inverter, be sure to disconnect all external connections of the inverter and the connection to the internal power supply of the equipment to ensure that the inverter is not accidentally re-powered. Use a multimeter to ensure that the interior of the inverter is completely free of electricity. Implement necessary grounding and short-circuit connections. For nearby potentially electrified components of the operating part, Use insulating fabric for insulation covering.

Operation status and environmental inspection: Check the inverter for any damage or deformation every six months, listen for any abnormal sounds during its operation, and when the system is connected to the grid for operation, inspect all variables, check if the main components are normal, and verify if the inverter casing is heating up normally. You can use a thermal imager or other equipment to monitor the system's heating situation and observe if the air intake and exhaust are normal. Check the humidity and dust in the surrounding environment of the inverter, and whether all the air inlet filters are functioning properly. Pay special attention to the ventilation of the air inlets; otherwise, the module may malfunction due to overheating.

System cleaning: Clean the inverter once every six months to one year, depending on the dust content in the usage environment. Check the cleanliness of the circuit board and components, inspect the temperature and dust of the heat sink. If necessary, use compressed air and turn on the fan to clean the module and replace the air filter.

Power circuit connection inspection: Half a year after the first debugging, and then every six months to one year thereafter, check whether the power cable connections are loose and tighten them according to the specified torque. Check whether the power cables and control cables are damaged, especially whether there are cut marks on the skin in contact with the metal surface. Check whether the insulating tape of the power cable terminal has fallen off.

Terminal and flat cable connection inspection: Check once a year whether the screws of the control terminals are loose and tighten them with a screwdriver. Check whether there is poor contact at the terminals of the main circuit and whether there are signs of overheating at the screw positions. Visually inspect the connections of the equipment terminals and the distribution of the ribbon cables.

Maintenance and replacement of cooling fans: Check the fan blades and other parts for cracks once a year, and listen for any abnormal vibration sounds during fan operation. If the fan shows any abnormal conditions, it should be replaced in a timely manner.

Circuit breaker maintenance: Conduct a routine inspection of the rust condition of all metal components every six months, carry out an annual inspection of contactors (auxiliary switches and micro-switches), ensure their mechanical operation is good, and check the operating parameters (especially voltage and insulation).

Safety function inspection: Check the emergency stop button and the stop function of the LCD every six months to one year, simulate the stop, and inspect the stop signal communication and warning labels. Replace them in a timely manner if necessary.

Special maintenance

Battery maintenance: Batteries only need to be kept charged frequently to achieve their expected lifespan. When connected to the mains power supply, it always charges the battery regardless of whether it is turned on or not, and provides overcharge and overdischarge protection functions. If the inverter equipment is not used for a long time, it is recommended to charge it once every four to six months. Under normal circumstances, the service life of a battery is 3 to 5 years. If it is found to be in poor condition, it must be replaced earlier. When replacing the battery, it must be carried out by professionals. When in normal use, the battery needs to be charged and discharged once every 4 to 6 months. After discharging, it should be recharged, and the standard charging time should not be less than 12 hours. In high-temperature areas, the battery should be charged and discharged once every two months. For standard machines, each charge should not be less than 12 hours. Before replacing the battery, the device must be turned off and disconnected from the mains power supply. Turn off the battery switch, remove metal items such as rings and watches, and use insulated handles and screwdrivers. Do not place tools or other metal objects on the battery pack. When connecting the battery wires, it is a normal phenomenon to have a small spark at the connection point, which will not pose a threat to personal safety or equipment. However, under no circumstances should the positive and negative terminals of the battery be short-circuited or reversed.

System parameter detection: Regularly detect system parameters and keep inspection records. If any abnormal phenomenon is found, identify the cause of the abnormality and take corresponding measures. If the cause of the abnormality cannot be identified, contact relevant professionals to search for it to prevent accidents and avoid affecting the system's usage.

Software upgrade: The software system of photovoltaic inverters will be constantly updated to provide better performance and functions. Regularly inspect and upgrade the software of the photovoltaic inverter to ensure its normal operation.