• Speedage Engineers (India) Private Limited

Resistance Boxes

Speedage Engineers offers Resistance Boxes. These are designed to meet requirement for both AC and DC application for EOT cranes, winches, rubber mills, steel mills, flour mills, coal mines, cement mills, power plants, conveyors, coke oven and blowers, etc., for speed control and developing starting torque. The basic types are stainless steel wire grid and stainless steel punched grid. These are designed and manufactured for current ratings from 10 to 260 A continuous resistors of higher ratings are manufactured by using 2 or more parallel paths. Resistors with short time ratings up to 3000 A or even more for neutral earthing are possible which are suitable for system voltage up to 11 kV and above, or any other requirement specifically. The temperature rise for stainless steel and punched steel grids is 375°C. Resistors can also be supplied to lower temperature rise such 220°C, etc., by suitably earthing the grids. Resistors for higher temperature rise have also been designed for short time duty, e.g., 510°C rise for cast iron grids or 760°C rise for stainless steel, which is permitted by IEEE standard 32.