Electrical Engineering Questions

Find Answer to Electrical Engineering Question What do you mean by Dc component of current in a circuit breaker?

Find Answer to Electrical Engineering Question What do you mean by Asymmetrical current (total current) in a circuit breaker?

A method of line protection employs a communication channel to compare electrical quantities at the terminals of the line. The nomenclature of pilot relaying often reflects the communication medium utilized in the application. Consequently, various terms such as wire pilot, carrier pilot, microwave pilot, and fiber-optic pilot protection systems are employed.

While referring to ANSI Standard CT Accuracy Classes, Code T. Indicates that the ratio must be determined by test. The T classification covers most wound-type CTs and any others whose core leakage flux affects the ratio appreciably. In case of T-Class CTs, the manufacturer can supply typical overcurrent ratio curves, data for these curves must … Read more

Failure to trip is a malfunction in the protective system, where it fails to initiate appropriate actions when a condition arises that necessitates intervention. This type of failure can lead to significant damage to the affected component if not promptly addressed by backup protection systems.

Undesired tripping, also known as false tripping, occurs when a relay unnecessarily trips due to a fault outside its designated protection zone or in the absence of any fault. This situation may arise when the protective system is configured with overly high sensitivity. This type of operation can result in unnecessary load outages, such as … Read more

Local backup relays serve as an alternative set of relays within a primary protection zone, functioning under specific conditions established for that zone. Typically, these local backup relays mirror the primary relays, operating independently under the same conditions. This setup forms an OR logic trip scheme, providing a robust safeguard against relay failures.

Backup relays are relays situated outside a designated primary protection zone, positioned in an adjoining zone. These relays are configured to activate in response to specified abnormalities occurring within the primary protection zone, operating independently of the primary relays. Serving as the secondary line of defence in the event of primary protection failure, backup relays … Read more

Primary relays (with primary sensitivity) are relays situated within a designated protection zone intended to respond to specified abnormalities within that zone. This protection scheme is meticulously crafted to safeguard the integral components of the power system. The track record of primary relaying is exceptionally strong, with well over ninety percent of all operations proving … Read more

Coordination of protective devices involves determining graded settings to achieve selectivity in safeguarding systems.