BS 5765(1979) : 1979 AMD 7913

Concerns d.c. resistive volt ratio boxes with fixed ratios and rated input voltage up to 1.5 kV and a class index of 1000 parts per million or better. Relates to all equipment which is built in or is supplied by the manufacturer as an essential part of the volt ratio box. Includes sections on nominal and true voltage ratio, circuit insulation voltage, leakage current screen, electrostatic screen, ripple content, common mode voltage, influence quantity, fiducial value, error, accuracy, parasitic voltage, multiple ratio VRBs, permissible variations, effect of self heating, voltage tests and other safety requirements, insulation resistance test, limiting temperature for storage, transport and use, markings, symbols, and documentation. BS AMD 7913 RENUMBERS THIS STANDARD TO BS EN 60524