The low-voltage neutral grounding resistor cabinet, during operation and under the condition of current flow, due to the non-uniformity of the resistive film, the current will not uniformly pass through each area of the resistor. Consequently, a certain area will inevitably exhibit a more concentrated phenomenon, leading to some noise generation.
The internal resistance mechanism of the low-voltage neutral grounding resistor cabinet and its operating mode in the circuit determine that a thermal effect is inevitably produced during the resistance's energization process, causing all components to generate heat. This thermal effect manifests as, when the temperature rises, the electric conductive particles in the low-voltage neutral grounding resistor cabinet undergo random thermal motion, causing the directed flow of current to fluctuate. This results in the formation of thermal noise current, which, through the resistor, generates noise voltage, hence termed as the resistor's thermal noise.
General low-voltage grounding resistor cabinets are typically configured with grounding transformers, resistors, intelligent controllers, and isolating switches. The low-voltage grounding resistor cabinet has been continuously developing well in the power industry and has a wide range of applications. It is usually installed in power systems such as power plants. In the power supply systems of industrial and mining enterprises' power distribution and transformation systems, the system operation methods for selecting these low-voltage grounding resistor cabinets in the power grid have been completed.
The low-voltage grounding resistor cabinet, also known as the resistor cabinet, is installed between the transformer neutral point or generator neutral point and the ground. The international and domestic industry standards are the same.
Each solution for a low-voltage earthing resistor cabinet must be carefully designed, requiring the expertise of the technical staff at the low-voltage earthing resistor cabinet manufacturer. The standards for low-voltage earthing resistor cabinets at the neutral point of transformers, or possibly between the neutral point of generators and ground, are the same internationally and domestically. When the earthing current is greater than or equal to 3A, it is typically necessary to install an earthing resistor cabinet at the neutral point to provide maintenance for the main transformer or generator.
