Neutral Grounding Cubicle
Our resistance units are regulary supplied for in the following industries and applications
INDUSTRIES
- Generation
- Oil, Gas and Petrochemical
- Distribution Subtation
- Gas Compressor Station
- Rollings Mills
- Electric Traction
- Testing Station
APPLICATIONS
- Dynamic Braking Resistors (DBR,S)
DBR,S are used to absorb the energy generated when stopping electric motors. They must be able to absorb this energy and cool down quickely between stops.
- Motor starting and speed control Resistors
Resistors are used where simplicity, relability and robust constraction are Key consideration for example: in mining locomotive.
- Testing
BORNA makes Resistor for testing:
– Batteries
– Power supplies
– Stand by power systems
- Dummy Load
- Load Banks
- Capacitor charge / discharge Resistors
- Cranes and other load equipments
- Bow Thrustors
STANDARDS
At present the only standard for NER,S is American National Standard specification standard requirements, terminology and test procedure for Neutral Grounding devices ANSI / IEEE – 32.
RESISTOR TYPES
Different types of resistors that are used in the NER all as followings:
- Wirewound
- Spring type
- Edgewound
- Grid type (Plate type)
- Ribbon type
- Casting alloy
Quality design features include all stainless steel (or Ni-cr) grids and terminals, high temperature insulation and welded construction. BORNA RESISTORS can be supplied with standard open frames or outdoor enclosures. The change in resistance with temperature during operation is small and predictable.
TEMPERATURE COEFFICENT OF RESISTANCE
Resistance increase of less than 10% per maximum temperature rise over the operating temperature range.
ENCLOSURE MATERIALS
The enclosure is made of stainless steel (2mm thickness) or hot dip galvanized steel or painted Mild steel coated with 80 micron RAL 7302.
ENCLOSURE PROTECTION RATING
- Degree of protection for frame: IP23
- Degree of protection for termination Box: IP54
Note: This rating is suitable for indoor and outdoor service.
STANDARD TESTS
According to the IEEE 32 standard, Routine tests on all units include:
- Resistance measurement at ambient temperature
- Applied potential test (Dielectric test)
- Impulse test only for Bushing
TECHNICAL SPECIFICATION
- Operating Voltage: Up to 72.5 kV
- Rated current: Up to 4000A
- Time: From a few seconds to continuous operation
Neutral Earthing Resistors are used for resistance grounding of industrial power systems. They are usually connected between earth ground and the neutral power transformer, power generator or artificial neutral The rating of NER is chosen to meet the requirements of the system protection scheme.
This will include consideration of maximum acceptable fault current, earth potential levels, and minimizing damage caused by the fault.
BORNA NER,S are designed to provide added safety to industrial distribution systems by limiting ground fault current to reasonable levels.