Product Usage
In the 6-35kV AC power grid, especially in cable powered networks, the use of resistance grounding is becoming increasingly widespread. However, when the transformer winding is connected using the "△" method and the neutral point of the power grid needs to be grounded, a grounding transformer must be installed, and then a resistor must be installed between the neutral point of the grounding transformer and the ground.
The ZW-JZG grounding resistance cabinet is a complete set of electrical equipment developed by our company for the above system requirements, including grounding transformers. It is installed in the power plant's auxiliary power system, substation power supply system, and industrial and mining enterprise distribution system, achieving the operation mode of these power grids using neutral point grounding through resistance.
Product features
1. Strong targeting and adequate protection
The ZW-JZG grounding resistance cabinet is suitable for situations where the transformer winding is connected using the "△" method and the neutral point is grounded with small or medium resistance. At this time, when a single grounding fault occurs in the power grid, it is necessary to immediately trip and cut off the faulty line. The ZW-JZG grounding resistance cabinet is installed on the low-voltage side or busbar of the transformer. When single-phase grounding occurs in the power grid, the grounding resistor provides additional resistive current to the grounding point, making the grounding current exhibit resistance capacitance properties, thereby ensuring that the generated overvoltage does not exceed 2.6 times the phase voltage.
2. Compact structure, easy to install
The ZW-JZG grounding resistance cabinet combines scattered Z-type grounding transformers, resistors, current transformers, measuring instruments, grounding protection output terminals, and other electrical equipment in a closed metal cabinet. It can also be equipped with isolation switches and lightning arresters, supplied in a complete set, with high safety and reliability, clear and neat layout, and easy installation, debugging, and operation and maintenance.
3. Careful selection of materials to fully ensure product quality
The grounding transformer inside the ZW-JZG grounding resistance cabinet is an epoxy resin cast or wound dry-type transformer, with a "ZN" - shaped primary winding. The resistor starter is made of special non-metallic materials, with large thermal capacity, small volume, long working time, and a wide range of resistance values, which can meet the needs of various usage scenarios.
4. Complete monitoring functions and provide analog output
The ZW-JZG grounding resistance cabinet is equipped with a dedicated lightning arrester, and can also be equipped with current transformers and action recorders. It can monitor the unbalanced current at the neutral point during normal operation, and record the number of actions in the event of a single-phase grounding fault. And it can provide analog output for protection and monitoring.
