ABB Relion REC670 Applications Manual page 126

Section 7
Current protection
Protection operate time:
Protection resetting time:
Breaker opening time:
The different characteristics are described in the technical reference manual.
tx : Definite time delay for step x . The definite time tx is added to the inverse time when inverse
time characteristic is selected. Note that the value set is the time between activation of the
start and the trip outputs.
INx> : Operate residual current level for step x given in % of IB .
INx>MaxEd2Set and INx>MinEd2Set should only be changed if remote setting of operation
current level,
setting. If
INx> is used by the function. If INx>MaxEd2Set is smaller than INx>MinEd2Set , the limits are
swapped.
kx : Time multiplier for the dependent (inverse) characteristic for step x .
IMinx : Minimum operate current for step x in % of IB . Set IMinx below INx> for every step to
achieve ANSI reset characteristic according to standard. If
signal will reset at current equals to zero.
txMin : Minimum operating time for 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.
Operate time
tx
txMin
IEC10000058 V2 EN-US
Figure 51:
In order to fully comply with the curves definition, the setting parameter
the value which is equal to the operate time of the selected IEC inverse curve for measured
current of twenty times the set current pickup value. Note that the operate time value is
dependent on the selected setting value for time multiplier
INxMult : Multiplier for scaling of the current setting value. If a binary input signal (ENMULTx) is
activated, the current operation level is increased by this setting constant.
ResetTypeCrvx : The reset of the delay timer can be made in different ways. The possibilities
are described in the technical reference manual.
120
INx> , is used. The limits are used for decreasing the used range of the INx>
INx> is set outside INx>MaxEd2Set and INx>MinEd2Set , the closest of the limits to
IMinx
Minimum operate current and operate time for inverse time characteristics
15-60 ms
15-60 ms
20-120 ms
Current
IEC10000058
1MRK 511 358-UEN A
IMinx is set above INx> for any step,
txMin shall be set to
kx .
Application manual