Abstract: A portable tester for determining the primary winding to secondary winding current ratio of a current transformer while that transformer is in service, including a current probe having a split core positionable around an active power line supplying current to the transformer, an AC to DC converter to convert the AC output of that probe to a first DC signal, another AC to DC converter for converting the secondary output of the current transformer under test to a second DC signal, and a ratio meter for converting the first and second DC signal into a visual display of the ratio of those signals. A mechanism is provided for assuring proper location of the decimal point on the ratio meter. Polarity and burden testing is also provided.
Type:
Grant
Filed:
April 29, 1985
Date of Patent:
July 19, 1988
Assignee:
Special Instruments Laboratory, Incorporated
Inventors:
Tullus E. Crawford, Claude R. Riley, Jr.