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Spare parts spare parts, the DCS control system of PLC system and the robot system spare parts,

Brand advantage: Allen Bradley, BentlyNevada, ABB, Emerson Ovation, Honeywell DCS, Rockwell ICS Triplex, FOXBORO, Schneider PLC, GE Fanuc, Motorola, HIMA, TRICONEX, Prosoft etc. Various kinds of imported industrial parts

CS513 3BSE000435R1 Industrial stocks

Static, dynamic and adaptive load shedding in power utility and industrial distribution systems
Generator protection. B. Features
one phase voltage as input variable
supervises the rate-of-change df/dt of the frequency
provision for enabling by absolute frequency
insensitive to DC component
insensitive to harmonics and other high-frequency signals
undervoltage blocking.Rate-of-change of frequency pick-up setting. Inadmissible settings:
df/dt = 0
df/dt > 0 for absolute frequency settings < fN
df/dt < 0 for absolute frequency settings > fN. Frequency Setting of the absolute frequency enabling criterion. Operation for overfrequency or underfrequency is determined by the absolute frequency setting:
Underfrequency for frequency settings < fN
Overfrequency for frequency settings > fN The absolute frequency criterion is disabled for a setting of ‘Frequency’ = 0. In this case, tripping is dependent solely on the rate-of-change setting df/dt. Inadmissible settings:
Frequency = fN
Frequency < fN – 10 Hz
Frequency > fN + 5 Hz. BlockVoltage Pick-up setting for undervoltage blocking (reset ratio approx. 1.05, reset time approx. 0.1 s). Delay Delay from the instant the function picks up to the generation of a tripping command. VoltageInp defines the voltage input channel. All voltage inputs may be selected with the exception of the special voltage inputs for the 100% ground stator fault protection. Blocked (U<) signals when the function is blocked by the undervoltage criterion.

Setting instructions

 Several rate-of-change of frequency stages are often needed and the additional stages are achieved by configuring the function as many times as necessary. Settings: Rate-of-change of frequency df/dt Absolute frequency Frequency Undervoltage BlockVoltage Delay Delay The rate-of-change of frequency function only trips when the rate-of-change is higher than setting, the absolute frequency criterion picks up and the voltage is not lower than the undervoltage setting. The additional absolute frequency criterion prevents unwanted operation of the rate-of-change function during power system transients. Where it is desired that the rate-of-change function should operate without regard to the absolute frequency, this is achieved by setting the absolute frequency criterion to ‘0’.