Protection operate time: 15-60 ms
Protection resetting time: 15-60 ms
Breaker opening time: 20-120 ms
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,
INx>
, is used. The limits are used for decreasing the used range of the
INx>
setting. If
INx>
is set outside
INx>MaxEd2Set
and
INx>MinEd2Set
, the closest of the limits to
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
IMinx
is set above
INx>
for any step,
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.
IMinx
Operate me
Current
tx
txMin
IEC10000058
IEC10000058 V2 EN-US
Figure 51: Minimum operate current and operate time for inverse time characteristics
In order to fully comply with the curves definition, the setting parameter
txMin
shall be set to
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
kx
.
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.
Section 7 1MRK 511 358-UEN A
Current protection
120
Application manual
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