LineTro110Tµr User Guide
June 2011 Page 7 of 16
4.
APPLICATION NOTES
The aim of this section is to describe how
the LINETROLL 110T
r indicator behaves
for different service situations and network
events.
4.1.
Energising a healthy line
As the magnetising inrush current of a line
can be very high, the indicator is provided
with 5 seconds inrush blocking which
prevents it from being activated until after
the line current has stabilised. Once the
blocking time has elapsed, the indicator is
enabled for fault detection.
.
Figure 5: Criterion of the blocking time.
a) shows the sequence when a fault occurs less
than 5 sec after line has been energised:
No Indication.
If, upon re-energising of a line, the unit is
already indicating due to a previous fault,
the unit will reset if the voltage or current
reset option is enabled. However even in this
case the indicator will flash for 30 seconds
(depending on the programming, see 4.7)
before finally extinguishing.
Figure 6: Delayed reset of flashing.
4.2.
Connecting a faulty line while the
indicator is activated
Closing a breaker onto a fault leads to
another trip almost instantly.
As the activated indicator needs 30 seconds
with the line energised in order to reset, it
will continue indicating.
Figure 7: Reclosing upon a faulted line.
