Hitachi Relion 670 Series Applications Manual page 184

Section 8
Current protection
GUID-B0E1F3F5-0B6E-47F9-84BC-C7BB5053B7FF V1 EN-US
Figure 69:
8.9.5 Setting guidelines
Common base IED values for the primary current (IBase), primary voltage (UBase) and primary
power (SBase) are set in global base values for settings function GBASVAL.
GlobalBaseSel: Selects the global base value group used by the function to define IBase, UBase and
SBase. Note that this function will only use IBase and UBase values.
8.9.5.1 Explanation of the setting parameters
Operation: Set to On in order to activate the function; set to Off to switch off the complete function.
StartCurr: Operation phase current level given in % of IBase.
Characterist: Selection of time characteristic: Definite time delay and different types of inverse time
characteristics are available; see Technical Manual for details.
tDef_OC: Definite time delay. It is used if definite time characteristic is chosen; it shall be set to 0.0 s
if the inverse time characteristic is chosen and no additional delay shall be added. Note that the
value set is the time between activation of the start and the trip outputs.
k: Time multiplier for inverse time delay.
tMin: Minimum operation time for all inverse time characteristics. At high currents the inverse time
characteristic might give a very short operation time. By setting this parameter the operation time of
the step can never be shorter than the setting.
Operation_UV: it sets On/Off the operation of the under-voltage stage.
StartVolt: Pickup voltage level given in % of UBase for the under-voltage stage. Typical setting may
be, for example, in the range from 70% to 80% of the rated voltage.
tDef_UV: Definite time delay. Since it is related to a backup protection function, a long time delay (for
example 0.5 s or more) is typically used. Note that the value set is the time between activation of the
start and the trip outputs.
EnBlkLowV: This parameter enables the internal block of the undervoltage stage for low voltage
condition; the voltage level is defined by the parameter BlkLowVolt.
178
I2P* I2P* I2P*
U2P* U2P* U2P*
OR OR
BLOCK BLOCK BLOCK
BLKOC BLKOC BLKOC
OR OR
BLKUV BLKUV BLKUV
Undervoltage seal-in of current start
© 2017 - 2023 Hitachi Energy. All rights reserved
VRPVOC VRPVOC
TRIP TRIP TRIP
TROC TROC TROC
TRUV TRUV TRUV
START START START
STOC STOC STOC
STUV STUV STUV
1MRK506375-UEN Rev. N
Trip output Trip output
t t t
GUID-2AE85EC4-669E-47C0-ADD4-3DBA83581096 v4
GUID-9B777E6D-602B-4214-9170-A44ED2D725BF v4
Railway application RER670
Application manual