Siemens 7SJ82, Manual

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As soon as an evolving fault is recognized (see chapter 6.45.4.13 Evolving-Fault Detection During Dead Time ),
switching to an automatic reclosing cycle for 3-pole interruption occurs. With the 3-pole cut-off of the
evolving fault, a separate adjustable dead time for the evolving fault begins. The total dead time is composed
of the part of the dead time that expired until the evolving fault was stopped for the first disruption plus the
dead time for the evolving fault. With the setting of the parameter
Dead time aft. evolv. fault
to
∞
(= invalid), no other automatic reclosing cycle is executed after tripping by the evolving fault. The tripping
through evolving faults is then finished.
[lopausjk-021212-01.tif, 1, en_US]
Figure 6-307 Cyclic Automatic Reclosing Function - Logic of the Dead Time for the Operating Modes: With
Tripping
Dead Time for Operating Modes with Pickup
In the dead time function block, the dead time corresponding to the type of short circuit that led to the trip
command is started. The automatic reclosing operating modes with pickup are only ideal for applications with
3-pole tripping. After expiration of the dead time, the automatic reclosing function changes to the status
Switch on.
Figure 6-308 shows the dead time logic.
There are 4 time stages that can be set differently:
•
Dead time after 1-phase short circuits
•
Dead time after 2-phase short circuits
•
Dead time after 3-phase short circuits
•
Dead time for evolving faults
In this way, setting the parameter
Dead time aft.1ph. pickup
to
invalid
avoids an automatic
reclosing after 3-pole tripping due to 1-phase short circuits. This also applies to
Dead time aft.2ph.
pickup
and
Dead time aft.3ph. pickup
.
6.45.4.12
Protection and Automation Functions
6.45 Automatic Reclosing Function
902 SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017