Neutral Grounding Resistors require regular maintenance. As a critical component of power system grounding protection, they are susceptible to environmental factors and aging during long-term operation. Maintenance prevents performance failures that could lead to safety accidents.
The maintenance cycle depends on the usage scenario: For general industrial power distribution systems, it is recommended to inspect every 6 months; for high-frequency operating scenarios such as new energy power plants and high-voltage substations, this should be shortened to once every 3 months. If installed in a humid or dusty environment, an additional 1-2 special inspections per year are required.
Specific maintenance items include two parts: First, visual inspection, checking for corrosion or deformation of the resistor casing, and loose or oxidized terminals. Any problems found should be addressed promptly. Second, resistance measurement, using specialized instruments to measure the resistance value. If the deviation from the initial value exceeds ±10%, internal aging or moisture problems should be investigated, and replacement should be considered if necessary.
Note that the power supply to the corresponding power system must be disconnected before maintaining the Neutral Grounding Resistor to avoid electric shock. Additionally, the heat dissipation components of the resistor should not be neglected. Excessive dust accumulation on the heat sink can lead to poor heat dissipation, overheating, and accelerated component aging. The heat sink should be cleaned after each maintenance.
