FUNCTION

Neutral Grounding Resistors are used to protect power transformers, power generators and other associated equipment in your power systems against 50/60 Hz faults (short circuit) and transient phenomena (lightning).

SPECIFICATIONS

There are six parameters needed to specify the neutral grounding resistor.1. Rated voltage line to neutral or system voltage.

2. Rated fault current.

3. Rated “duration time” of the line to neutral voltage not exceeding the allowable temperature rise.

4. Rated Resistance.

5. Application environment, indoor or outdoor.

6. Enclosure material, ss plate or normal cold rolled sheet.

RANGE

• Rated current: from 1 amp to 2000 A

• Rated voltage: from 0.4 to 35kV

• Rated Resistance: from 1 ohm to 2000 ohm

• Rated time: 1 sec to continuous time rating

TESTING AND QUALITY

All Mingrui Neutral Grounding Resistors are designed, rated, manufactured and tested in strict compliance with IEEE-32. Routine tests performed on each Neutral Grounding Resistor are measurement of resistance, high voltage power frequency, insulation measurement, aspect verification, dimensional control. Mingrui’s internal quality system has been developed and certified under ISO 9001 quality system

CONSTRUCTION

Standard unit includes the stainless steel resistor assembly plus all the required insulators, internal connections and hardware installed in a standard safety enclosure. Neutral Grounding Resistor units are completely assembled, prewired, and tested at our facility. For shipping all units are crated for added protection and ease of handling.

ENCLOSURE FEATURES

• Forged eyebolts in all four corners for easy hoisting.• Removable front and rear louvered covers for easy access for connection and inspection.

• Corrosion resistant nameplate provides complete ratings and manufacturers information.

•Heavy gauged enclosure polyester powder coated finish provides maximum protection.

ENCLOSURE OPTIONS

•Stainless steel, cold rolled plate construction. Custom paint finish is available.• Top or side mounted entrance bushing(s).• Screened covers for indoor applications.• Support stands for elevating the enclosure above ground.

OPTIONS

• Current or groundingl transformers mounted and prewired at our facility• ON or OFF Load disconnecting switches