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. This technical report refers to the electrical protections of all 132kV switchgear. All calculations are based on the available documentation/ information. This standard mandates that generator, transmission, and distribution owners establish a process for developing new and revised protection settings and properly coordinate their systems wi h interconnected utilities as part of Requirement 1. The protective philosophy is fundamentally grounded on the understanding that faults or abnormal operating. In HV (High Voltage) and MV (Medium Voltage) substations, relay protection safeguards critical assets such as transformers, circuit breakers, and lines.
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