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. Pick Up Current Definition: The current level at which the relay begins to operate, overcoming the controlling force. Instantaneous units should be set so they do not trip for fault levels equal or lower to those at busbars or elements protected by downstream instantaneous relays. These calculations are critical in industrial. Motor protection relay settings are calculated from motor nameplate data, current transformer ratios, and system grounding method.