Grid resistors' resistive element enables more stable TCR

The grid resistors utilising the new magnetic stainless steel material provide a TCR of ±365ppm/°C and deliver superior performance and corrosion resistance for dynamic braking resistors, testing load banks, motor control and other applications requiring a minimal change in resistance as the elements increase in temperature. Devices using a non-magnetic stainless steel alloy offer a TCR of ±930ppm/°C and are optimised for harmonic filtering and current limiting applications, in addition to those requiring reduced noise emissions, such as dynamic braking in elevators and other industrial equipment.

Vishay's GRE1 and GRE2 series resistors combine high power ratings up to 24kW with operating temperatures to +400°C and a robust design. Featuring a steel plate element, ceramic insulators and multiple taps, the devices provide high reliability with a welded construction and double insulation for maximum cooling efficiency. To provide ground fault, overvoltage, and short circuit protection for generators and transformers in wye (star) configurations, NGR devices feature GRE1 resistors mounted in a rugged, weatherproof IP23-rated enclosure with high-temperature performance to +760°C.

Production quantities of grid resistors with the new stainless steel resistive elements are available now, with lead times of three to four weeks.