Title :
An Improved Type of D-C Wattmeter of the Shunted Type
Author_Institution :
Development engineer in the meter department of Westinghouse Electric and Manufacturing Company, Newark, N. J.
Abstract :
While wattmeters for high current values of a-c power are universally used in connection with instrument transformers, d-c power is ordinarily measured by using separate ammeters and voltmeters on account of the difficulty in making a heavy-current d-c wattmeter. Although large direct currents are conveniently measured by use of the shunt and millivoltmeter, shunted-type d-c wattmeters have in the past been somewhat unsatis-factory. An improved d-c wattmeter is described which corresponds in accuracy and sensitivity to the usual permanent-magnet moving-coil ammeter and operates from the usual ammeter shunt.
Keywords :
Ammeters; Coils; Current measurement; Electrodynamics; Instruments; Magnetic separation; Magnetic shielding; Power measurement; Tellurium; Wattmeters;
Journal_Title :
American Institute of Electrical Engineers, Transactions of the
DOI :
10.1109/T-AIEE.1941.5058188