Neutral ground resistors offer line-neutral voltage to 8kV up to +760C
A new series of neutral ground resistors for industrial power systems has been introduced by Vishay. Consisting of the company's GRE1 high-power, high-current grid resistors mounted in rugged, weatherproof IP23-rated enclosures with extremely high-voltage insulation, Milwaukee Resistors the NGR series devices combine high line-neutral and system voltages with high-temperature performance to +760C.
Offering a convenient drop-in replacement for competing solutions, NGR series resistors are designed to provide ground fault, overvoltage, and short circuit protection for generators and transformers in wye (star) configurations without exceeding the temperature limitations outlined by IEEE-32. The devices offer line-neutral voltage from 1.39kV to 8kV, system voltage from 2.4kV to 13.8kV, and current ratings from 100A to 1000A. Resistance for the resistors ranges from 1.39ohm to 80ohm with tolerance of ±10%.
The RoHS-compliant resistors offer a tied live design to eliminate floating voltages in the assembly and lifting eyes for safe and easy installations. Featuring a stainless steel element, ceramic insulators, and multiple taps, the NGR series provides high reliability with a welded construction. Additionally, the devices' open design allows for maximum cooling efficiency. The units are offered in modular or custom designs, says the company.