GE GEK-106273L, Инструкция по эксплуатации

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PRODUCT DESCRIPTION
GEK-106273L MIF Digital Feeder Protection 2-7
2.2.2. PHASE INSTANTANEOUS OVERCURRENT UNITS (50PH, 50PL)
The MIF provides 2 phase instantaneous overcurrent units, 50PH (‘H’ for high pickup) and 50PL (‘L’ for low pickup).
Each one can be enabled/disabled and set independently. The settings from these units allow to set the pickup value
from 0.1 to 30 times the rated current (or 0.005-0.12 A in case of sensitive ground models), and the time delay from
0.00 to 600.00 seconds.
2.2.3. GROUND TIME OVERCURRENT UNIT (51N)
The Ground Time Overcurrent unit offers the same setting possibilities as the Phase Time Overcurrent unit. The
ground current can be obtained from a residual connection on the CTs. For a more sensitive ground current
detection, a window type (zero sequence) CT taking the three phases inside its windows can be used. Refer to figure
3.6 for more details.
2.2.4. GROUND INSTANTANEOUS OVERCURRENT UNITS (50NH, 50NL)
The MIF relay provides 2 Ground Instantaneous Overcurrent Units, 50NH (‘H’ for High pickup) and 50NL (‘L’ for Low
pickup). The settings and ranges available for these units are the same than the ones described for the Phase
Instantaneous Overcurrent Units, 50PH and 50PL.