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5.2.4
Reset setting for inverse time
tripping characteristics in the phase
current
path
To ensure tripping, even with recurring fault pulses
shorter than the set trip delay, the reset mode for in-
verse time tripping characteristics can be switched
over. If the adjustment tRST is set at 60s, the tripping
time is only reset after 60s faultless condition. This
function is not available if tRST is set to 0. With fault
current cease the trip delay is reset immediately and
started again at recurring fault current.
5.2.5
Current setting for high set element
(I>>)
The current setting value of this parameter appearing
on the display is related to the nominal current of the
relay
This means: I>> = displayed value x I
N
.
When the current setting for high set element is set out
of range (on display appears "EXIT"), the high set ele-
ment of the overcurrent relay is blocked.
The high set element can be blocked via terminals
E8/D8 if the corresponding blocking parameter is set
to bloc (refer to chapter 5.2.25).
5.2.6
Trip delay for high set element (t
I>>
)
Independent from the chosen tripping characteristic for
I>, the high set element I>> has always a definite-time
tripping characteristic. An indication value in seconds
appears on the display.
The setting procedure for forward- or backward faults,
described in chapter 5.2.3, is also valid for the trip-
ping time of the high set element.
5.2.7
Relay characteristic angle RCA
The characteristic angle for directional feature in the
phase current path can be set by parameter RCA to
15°, 27°, 38°, 49°, 61°, 72° or 83°, leading to the
respective reference voltage (see chapter 4.3).
5.2.8
Voltage transformer connection for
residual voltage measuring
(3pha/e-n/1:1)
Depending on the connection of the voltage trans-
former of ER/XR-relay types three possibilities of the
residual voltage measurement can be chosen
(see chapter 4.4)
5.2.9
Pickup value for residual voltage
U
E
(ER/XR-relay type)
Regardless of the preset earth current, an earth fault is
only identified if the residual voltage exceeds the set
reference value. This value is indicated in volt.
5.2.10 Pickup current for earth fault
element
(I
E>
)
(Similar to chapter 5.2.1)
The pickup value of X and XR-relay type relates to % I
N
.
5.2.11
WARN/TRIP changeover
(E/X and ER/XR-relay type)
A detected earth fault can be parameterized as fol-
lows:
a) "warn" only the alarm relay trips
b) "TRIP" the trip relay trips and tripping values are
stored.
5.2.12 Time current characteristics for
earth fault element (CHAR IE;
(not for ER/XR-relay type)
(Similar to chapter 5.2.2)
5.2.13 Trip delay or time multiplier for
earth fault element (t
IE>>
)
(Similar to chapter 5.2.3)
5.2.14 Reset mode for inverse time
tripping in earth current path
(Similar to chapter 5.2.4)