Breakers & Relays
Protective Relay Frustrations
Protection of Electrical Power Transformers
Breakers & Relays
Power Factor Testing of Circuit Breakers
Detecting contamination and deterioration in SF6 breakers to ensure longevity
BY LINDA NOWAK, Doble Engineering Company
The purpose of “Doble testing”, or power factor testing, SF6 (sulfur hexafluoride) circuit breakers is to detect the presence of contamination and/or deterioration of the breaker’s insulating system. This process will allow corrective actions to be taken to ensure the integrity of the breaker.
The Doble test is completed by measuring the insulation’s dielectric-loss and capacitance and...
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