ABB RELION REB670, Applications Manual

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PU_37 = 70% (of IBase ); Current level for undercurrent pickup
tUC = 5s ; Time delay for undercurrent trip
Undercurrent feature is blocked by operation of Reconnection inhibit
feature.
Reactive power overload feature:
Operation QOL = Enabled ; to enable this feature
UP_QOL = 130% (of SCB MVAr rating); Reactive power level required for pickup.
Selected value gives pickup recommended by international standards.
tQOL = 60s ; Time delay for reactive power overload trip
Harmonic voltage overload feature :
OperationHOL = Enabled ; to enable this feature
Settings for definite time delay step
HOL_DT_V = 200% (of SCB voltage rating); Voltage level required for pickup
tHOL_DT = 10s ; Definite time delay for harmonic overload trip
Settings for IDMT delay step
PU_HOL_DT_V = 110% (of SCB voltage rating); Voltage level required for pickup of
IDMT stage. Selected value gives pickup recommended by international standards.
k_HOL_IDMT = 1.0 ; Time multiplier for IDMT stage. Selected value gives operate
time in accordance with international standards
tMax_HOL_IDMT = 2000s ; Maximum time delay for IDMT stage for very low level of
harmonic overload
tMin_HOL_IDMT = 0.1s ; Minimum time delay for IDMT stage. Selected value gives
operate time in accordance with international standards
7.10.3.1 Restrike detection
GUID-114747A5-0F7C-4F48-A32D-0C13BFF6ADCE v1
Opening of SCBs can be quite problematic for certain types of circuit breakers (CBs).
Typically such problems are manifested as CB restrikes.
1MRK 505 370-UUS A
Section 7
Current protection
Busbar protection REB670 2.2 ANSI 241
Application manual