Measuring molded case circuit breaker resistance

Author

Shea, John J. ; Bindas, John A.

Author_Institution

Westinghouse Sci. & Technol. Center, Pittsburgh, PA, USA

fYear

1992

fDate

18-21 Oct. 1992

Firstpage

159

Lastpage

165

Abstract

Molded case circuit breaker resistance is measured under various conditions to demonstrate the need for more standardized procedures when performing millivolt drop measurements. Breakers, rated at 600 V/sub ac//250 A/sub ac/ and 120/240 V/sub ac//50 A/sub ac/, with silver-tungsten (Ag-W) contacts are used to show that contact resistance can cause variability in circuit breaker resistance and to demonstrate the influence of current, time, contact temperature, and applied voltage on contact resistance. Based on these results, guidelines are developed for making reliable resistance measurements on molded-case circuit breakers (MCCB) when using the millivolt drop technique.<>

Keywords

circuit breakers; contact resistance; electric resistance measurement; electrical contacts; 120 V; 240 V; 250 A; 50 A; 600 V; Ag-W contacts; MCCB; contact resistance; contact temperature; current effect; millivolt drop measurements; molded case circuit breaker resistance; resistance measurements; time effect; Circuit breakers; Circuit testing; Computer aided software engineering; Contact resistance; Current measurement; Electrical resistance measurement; Guidelines; Performance evaluation; Temperature; Voltage measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Electrical Contacts, 1992., Proceedings of the Thirty-Eighth IEEE Holm Conference on

Conference_Location

Philadelphia, PA, USA

Print_ISBN

0-7803-0576-0

Type

conf

DOI

10.1109/HOLM.1992.246920

Filename

246920