Common faults of solar inverters and how to deal with them

1. Leakage fault: The root cause of this type of problem is the installation quality problem, which is caused by choosing the wrong installation location and low-quality equipment. There are many fault points: low-quality DC connectors, low-quality components, unqualified component installation heights, low-quality grid-connected equipment or water leakage. Once similar problems occur, you can find the leakage points by sprinkling powder and insulate them well. Work to solve the problem. If the problem is with the material itself, the material can only be replaced.

2. DC overvoltage: As components pursue high-efficiency process improvements, power levels are constantly updated and rising. At the same time, component open circuit voltage and operating voltage are also rising. Temperature coefficient issues must be considered during the design stage to avoid overvoltage at low temperatures that may cause hard damage to the equipment.

3. The inverter does not respond when it is turned on: Please make sure that the DC input line is not connected reversely. Generally, the DC connector has an anti-fooling effect, but the crimping terminals do not have an anti-fooling effect. Carefully read the inverter manual to ensure that the positive and negative poles are connected before crimping. very important. The inverter has built-in reverse connection short-circuit protection and will start normally after restoring normal wiring.

4. Low insulation resistance: use the elimination method. Unplug all the strings on the input side of the inverter, and then connect them one by one. Use the function of detecting insulation impedance when the inverter is turned on to detect the problem string. After finding the problem string, focus on checking whether the DC connector has a water-immersed short-circuit bracket. Or melt the short-circuit bracket. In addition, you can also check whether the component itself has black spots on the edge and is burned, causing the component to leak through the frame to the ground grid.

   5.Low bus voltage: If it occurs in the morning/late hours, it is a normal problem because the inverter is trying extreme power generation     conditions. If it occurs during normal daytime, the detection method is still the elimination method, and the detection method is the             same    as item 1.

6. Power grid failure:

    Grid overvoltage: The early work of surveying the grid's heavy load (high power consumption during working hours)/light load (low              power       consumption and rest time) is reflected here. Survey the health of the voltage at the grid connection point in advance, and          work with the inverter manufacturer Communicating the power grid situation and combining technology with each other can ensure that      the project design is within a reasonable range, and do not "take it for granted". Especially for rural power grids, inverters have strict          requirements for grid-connected voltage, grid-connected waveform, and grid-connected distance. Most of the causes of power grid         overvoltage problems are that the light load voltage of the original power grid exceeds or is close to the safety protection value. If the         grid-connected lines are too long or have poor crimping, resulting in excessive line impedance/inductance, the power station will not be     able to operate normally and stably. The solution is to find the power supply bureau to coordinate the voltage or correctly choose the         grid connection and strictly control the construction quality of the power station.

  Grid undervoltage: This problem is consistent with the treatment of grid overvoltage. However, if an independent phase voltage is too          low,   in addition to incomplete load distribution of the original grid, a power outage or circuit break in the phase grid will also cause this    problem. virtual voltage. Power grid over/under frequency: If such problems occur in the normal power grid, it proves that the health of t      The power grid is very worrying. There is no voltage in the power grid: just check the grid connection line.