Use this Protection Relay Setting Calculator to calculate pickup current, time multiplier settings (TMS), operating time, coordination time interval (CTI), and plug setting multiplier (PSM) using fault current, CT ratio, and IEC 60255 curve parameters. Protection relays employ a wide range of configurable parameters to identify defects & trip the breaker in a controlled & selected manner. Understanding each setting facilitates proper relay coordination. These calculations are critical in industrial. Good and reliable selectivity of the protection is essential in order to limit the supply interruption to the smallest area possible and to give a clear indication of the faulted part of the network. This makes it possi-ble to direct the corrective action to the faulty part of the network and the. Motor protection schemes should cause minimum process downtime while providing adequate protection. These schemes should allow operators to maximize process availability.
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