TB XRI1-IR 02.00 E
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6.1.4
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.
6.1.5
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
C1/C1L or C1/C1H if the corresponding blocking
parameter is set to bloc (refer to chapter 6.1.12).
6.1.6
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 6.1.3, is also valid for the trip-
ping time of the high set element.
6.1.7
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).
6.1.8
Nominal frequency
The adapted FFT-algorithm requires the nominal fre-
quency as a parameter for correct digital sampling
and filtering of the input currents.
By pressing <SELECT> the display shows "f=50" or
"f=60". The desired nominal frequency can be ad-
justed by <+> or <-> and then stored with <ENTER>.
6.1.9
Adjustment of the slave address
Pressing push buttons <+> and <-> the slave address-
can be set in range of 1-32.
6.1.10
Circuit breaker failure protection
t
CBFP
The CB failure protection is based on supervision of
phase currents during tripping events. Only after trip-
ping this protective function becomes active. The test
criterion is whether all phase currents are dropped to
<1% x I
N
within the time t
CBFP
(Circuit Breaker Failure
Protection, adjustable between 0.1 - 1.6s). If not all of
the phase currents have dropped to <1% x I
N
within
this time, CB failure is detected and the related relay
activated. The CB failure protection function is deacti-
vated again as soon as the phase currents have drop-
ped to <1% x I
N
within t
CBFP
6.1.11
Display of the activation storage
(FLSH/NOFL)
If after an activation the existing current drops again
below the pickup value, e.g. I>, without a trip has
been initiated, LED I> signals that an activation has
occured by flashing fast. The LED keeps flashing until it
is reset again (push button <RESET>). Flashing can be
suppressed when the parameter is set to NOFL.
