Sepam - HV/MV Protection and control units (ENG) - Trinet

Phase undercurrentANSI code 37Block diagramfunction n°F221I1I < Is15ms0&T0F221/2OperationThis protection is single-phase:c it picks up when phase 1 current is less than the setpoint Is,c it is inactive when the current is less than 1.5%of In,c it is insensitive to current drops (breaking)due to circuit breaker tripping,c it includes a definite time delay T.Tt0 0.015In Is IOperating principle.1.06IsIs0.015Ininstantaneousoutputinstantaneoustime delayedCase of current sag.1.06IsIs0.015Ininstantaneousoutput = 0instantaneoustime delayed = 0Case of circuit breaker opening.0.015 Inoutputs available for control logic(106 ±5)% for Is > 0.1 In50 ms i T i 655 s±2% or ±25 ms10 ms or 1 digit< 50 msT< 25 ms10 ms < t < 40 ms< 45 msinstantaneous F221/1time delayed F221/2remote reading, remote setting* (2)function numberidentification number 122hparameters Is set point unit: % (3)(order of parameters) T time delay unit : 10 x ms(1)in reference conditions (IEC 60255-6).(2)the data formats are defined in the manuals which describe each communication protocol.(3)percentage of load basis currentSensorsThis protection is related to the CTs connectedto the following connector:current sensor connector1A or 5A CT 2BCSP2L1, 2L2, 2L3F221/1* function available as of version 9802 SFT2800.Protection functions2/37