Understanding each setting facilitates proper relay coordination. PSM – Plug Setting Multiplier (Current Setting Multiplier) What is PSM? 2). EL – Earth Leakage Setting / Earth Fault. Protection relays employ a wide range of configurable parameters to identify defects & trip the breaker in a controlled & selected manner. TSM – Time. 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. The power system consists of generators, transformers, transmission lines, and other equipment whose costs is in millions of dollars. All calculations are based on the available documentation/ information. They should not be installed purely as a means of protecting systems against overloads.
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