H. K. Electric Co.

Resistance boxes are used to add resistance to an electric motor circuit for modifying the performance characteristic of slip ring induction motors of EOT cranes, rubber mills, steel rolling mills, cement mills, power plants, conveyors, coke oven, blowers, etc. For speed control and developing starting torque with low starting currents. They are also used as Dynamic Braking Resistor for VVVF AC drives, electric loading of ac alternators, degeneration, and dynamometers. Resistors are designed to meet the requirements of both A.C. & D.C. applications. . 

A Decade Resistance Box is a precision instrument that provides a selectable resistance value using a combination of rotary switches or dials. Each "decade" corresponds to a specific range (e.g., 1 Ω, 10 Ω, 100 Ω, etc.), allowing the user to quickly and accurately set a desired resistance value for testing, calibration, simulation, or circuit development.