Brief Introduction to product
With neutral grounding resistance is installed, when nonmetal grounding, the current flowing through grounding point and neutral would be much less than that when metal grounding. Meanwhile sound phase voltage rise is lowered a lot and zero-sequence voltage is half of that when single-phase metal grounding. Therefore, adopting neutral grounding via resistance could decrease transient overvoltage when single-phase grounding, and eliminate arc flash hazards like transient overvoltage and some resonant overvoltage, and moreover it could adopt simple relays to quickly locate the fault line and clear it up.
Mingrui has outstanding technical researching team and superior equipments, specially concentrate on research & development, production, sales and service of neutral grounding series products of power distribution system. The transformer neutral grounding resistance we developed and produced is applicable to 6~35KV power distribution grid of cable lines in cities, large industrial enterprises, factories, airports, seaports, subway and etc. as well as 0.66KV system in mine digging and 0.4kv/6kv/10kv system in power plants.
The design of the product complys with the following standards:
IEC726 Dry-Type Power Transformer
IEC60-1 Experimental Technique of High Voltage
IEC60529:2001 Enclosure Protection Degree (IP code)
IEEE32-1972 Technique Terms and Experiment of Neutral Grounding Device
IEC60081 Insulation Co-ordination of Transmission and Distribution Device of High Voltage
The Characteristeic of the Product
3.1 Adopted high quality imported stainless steel or domestic stainless steel electric heating metal material,
the product operates safely and reliably with the advantages of high conductivity, high temperature coefficient, corrosion resistance, thermostability, good oxidation resistance, high tensile strength, resistance value stability and etc.
3.2 The device also could be applied in medium power distribution system. When transformer is angle-connected, independent grounding transformer could be installed with which the neutral point and resistance are connected.
3.3Resistance value could be designed from 1ohm to 2000ohm and current from 1A to 2000A
3. 4 The cabinet could be installed indoor or outdoor. As the cabinet body is corrosion-resistant and of high protection grade, made from stainless steel plate or painted cold rolled steel plate.
3.5 The counting function could be added to the device, which records times of resistance grounding.
3.6 Isolated switch could be added which convenient examination and repair and so does temp. or humidity controller.
3.7 Intelligent monitor is at customers’ option, which could monitor un-balanced current of neutral point when resistance cabinet is in normal operation, temp. of resistance panel, and temperature of inside cabinet, measure transient current and records grounding times when single-phase grounding happens, reserve communication interface which could send monitored and recorded to master-control room so as to let operating people get the information in the first time.
Neutral grounding resistor cabinet for transformer Images