• Valseshika Electron Devices

Precision Dc Potentiometer

Vaiseshika Electron Devices offers a precision DC Potentiometer, Type 9408. This has been designed to provide the highest standards of accuracy over a period of many years without any maintenance, whilst at the same time allowing rapid and easy operation. The instrument uses the company's unique low resistance precision instrument switch, developed after several years of research into the fundamental factors affecting contact resistance. The stationary contacts are silver-clad copper bars, mounted in a robust insulating frame. The brush, which is composed of several contact springs, each of which is independent of the others and is unrestricted in its movement, makes a bridge contact between adjacent bars in a symmetrical manner. As a result, low and consistent contact resistance is achieved without high contact pressure or mechanical wear. After a life test of some 20,000 operations, the switch was still mechanically sound and its stability had actually improved in the narrow range specified. Decade switching is used throughout the potentiometer. Resistance coils are mounted directly on the switch units so that interconnecting wires are reduced to a minimum.