33kV Neutral Earthing Resistor Cabinet
Distribution network system neutral point by way of resistance earthing in Europe and the United States and other developed countries have more than 100 years of application history, the application of power grids in China are also increasingly popular.
In order to better limit the over-voltage level of the system and to quickly select and remove the fault line when the compensation line of the arc-suppression coil earthing system compensation line cannot meet the needs of the rapid development of the system, a neutral point earthing method is adopted. In the power generation system in order to limit the engine outlet flow of fault current and limit the level of over-voltage, but also more use of neutral earthing resistance by way.
The earthing of the neutral point can effectively limit the intermittent arc earthing over-voltage, reduce the system operation overvoltage, eliminate the system resonance over-voltage, easy to configure single-phase ground fault protection, can effectively remove the fault line in a short time. So as to reduce the insulation level of the system equipment, delay the service life of the system equipment, and improve the safety and reliability of system operation.
We have professional R&D team and advanced equipment. The company introduces and localizes advanced foreign technologies, and has always focused on the research, development and production of neutral earthing products which have good effect on reducing overvoltage and improving security and reliability of power systems. The company developed series of neutral earthing stainless steel resistor cabinets with import special stainless-steel alloy for 6 – 35KV power systems. Earthing capacitance currents in a cable power system is comparatively large.
The product is made of high quality imported stainless steel or domestic stainless steel electric metal material. It has the characteristics of high conductivity, high temperature coefficient, corrosion resistance, high temperature resistance, high oxidation resistance, high tensile strength and stable resistance. The product runs safely and reliably. In the medium voltage distribution system, if the transformer is delta connection, you need to install Z-type earthing transformer, in order to draw the neutral point for the system to install the neutral point earthing resistance.
Altitude: no more than 4000m
Ambient temperature: -40°C ~ +60°C
Relative humidity: no more than 95% (25°C)
Installation site: there should be free of chemical etching gases, steam or explosive dust in the air
Power frequency: 48 ~ 52Hz (50Hz system), 58 ~ 62Hz (60Hz system)
Installation environment: Indoor, outdoor
Installation point of resistor: normally the neutral point voltage displacement shall not be more than 3% of phase voltage; special operation conditions shall be stated at the time of ordering.
DL/T780-2001 Neutral point earthing resistors for distribution systems
GB6450 Dry-type power transformers
DL/T620-1997 Overvoltage protection and insulation coordination for AC electrical installations
GB/T16927.1-1997 High - voltage test techniques - Part 1: General test requirements
GB1208-1997 Current transformers
GB/T4208-2017 Shell protection class (IP code)
IEEE 32-1972 Standard Technical, terminology and tests for neutral earthing devices
