The neutral point through resistance grounding method has been used in my country's distribution network system in the 1990s, and is currently widely used in my country's urban power supply system, power plants, railways, metallurgy and petrochemical systems.
Our company is an early domestic manufacturer of R&D and production of neutral point resistance devices for power systems. The complete set of generator neutral point grounding resistance can meet the requirements of power neutral point equipment in terms of thermal and electrical performance. It has high temperature resistance, high resistivity, small resistance temperature coefficient, high tensile strength and toughness. It has excellent mechanical properties and is a special complete set of equipment for 0.4kV-65kV equipment.
Resistance cabinet implementation standard:
DL/T 780-2001 Neutral grounding resistor for power distribution system
GB 6450-1986 Dry-type power transformers
DL/T 620-1997 Overvoltage protection and insulation coordination of AC electrical installations
GB 763-1990 Heat generation of AC high-voltage electrical appliances during long-term operation
GB/T 16927-2011 High Voltage Test Technology
GB 1208-2006 Current Transformer
GB/T 4208-2017 Protection class of enclosure (IP code)
IEEE 32-197 Techniques, Terminology, and Tests for Grounding Neutrals
GB 311-2012 Insulation coordination
GB 11022-2011 Common technical requirements for high-voltage switchgear and control equipment standards
JB/T 10777-2018 Neutral point grounding resistor
Resistance Cabinet Operating Environment
1. Altitude: no more than 3000m;
2. Ambient temperature: -30℃～+50℃;
3. Relative humidity: not more than 95% (25℃);
4. Installation site: There is no chemical corrosive gas and vapor in the air, no explosive dust;
5. Power grid frequency: 48~52Hz (50 Hz system), 58~62 Hz (60 Hz system);
6. Applicable to: indoor and outdoor;
7. Installation point: under normal conditions, the neutral point displacement does not exceed 3% of the operating phase voltage.
