Please use this identifier to cite or link to this item:
Title: A Test of Circuit Breakers Under Harmonic Loading Conditions
Authors: Estrada, Tony
Briggs, Stephen J.
Khosla, Naresh
Construction Engineering Research Laboratory (U.S.)
Keywords: Electric circuit-breakers
Electric currents
Military bases--United States--Power supply
Publisher: Construction Engineering Research Laboratories (U.S.)
Series/Report no.: Technical Report (Construction Engineering Research Laboratories (U.S.));no. 96/13
Abstract: Harmonic currents in Army installation power systems can cause voltage distortion, overheating of system components, and load disruption. The U.S. Army Center for Public Works also has periodically received reports of unexplained nuisance circuitbreaker tripping, which in theory might be caused by harmonics. No industry standard literature is available on the behavior of circuit breakers under harmonic loading conditions, however. The objective of this work was to test the effects of harmonic loading conditions on three common types of low-voltage, molded-case circuit breakers used indoors on Army installations: thermal-magnetic, magnetic-only, and solid state. This experiment detected no nuisance tripping with any of the breakers tested. Additionally it was found that varying harmonic loading conditions did not affect manufacturer-specified trip times for thermal-magnetic or solid state circuit breakers. However, under moderate overload conditions, the same experimental harmonic conditions caused hazardous overheating and trip failure in the magnetic-only circuit breakers. Based on a review of related nonexperimental industry literature on circuit breaker design and performance, the authors postulate that inherent design characteristics leave thermal-magnetic and solid state circuit breakers unaffected by harmonics. The literature also suggests that the construction of the instantaneous tripping element in the magnetic-only breakers may account for their overheating and trip failure in the experiment.
Description: Technical Report
Gov't Doc #: USACERL Technical Report 96/13
Rights: Approved for public release; distribution is unlimited
Size: 40 pages / 4.286Mb
Types of Materials: PDF/A
Appears in Collections:Technical Report

Files in This Item:
File Description SizeFormat 
USACERL Technical Report 96-13.pdf4.39 MBAdobe PDFThumbnail