Siemens 6MD85, Manual

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Evolving-Fault Detection During Dead Time
Evolving faults are short circuits, which occur after switching off a short circuit during dead time. This may be
the case during 1-pole tripping and there is a short circuit in the non-switched conductors after this.
After 3-pole tripping there may also be evolving faults if the line is fed through a second (non-3-pole) opened
circuit breaker, for example, for systems with a 1 1/2 circuit breaker layout.
The evolving-fault detection is divided into components:
•
Detection of Evolving Faults
•
Evolving-Faults Processing
•
3-pole circuit-breaker intertripping during evolving faults
The procedure during evolving faults is illustrated in Figure 7-43 .
Detection of Evolving Faults
For the detection of an evolving fault, the following criteria can be selected through parameters:
•
Parameter
Evolving-fault detection
=
with trip
For this setting, any tripping during the dead time leads to evolving-fault detection. At any tripping it is
decided if an internal protection function is tripped or if the tripping is signaled through a binary input.
Thus, it does not matter if the tripping-protection function is configured for the start of the automatic
reclosing function or not.
•
Parameter
Evolving-fault detection
=
with pickup
Evolving faults are detected if during the dead time a protection function configured for the automatic
reclosing function start is picked up or if an external pickup is recognized through a binary input.
•
Binary input
>Evolving fault start
The evolving-fault detection can also be introduced through a binary input without an internal protection
pickup being available.
Reaction to Evolving Faults
After a recognized evolving fault, the automatic reclosing function can be influenced in 2 ways.
•
Parameter
Response to evolv. faults
=
blocks 79
As soon as an evolving fault is recognized, the reclosing function will be blocked. There are no other
reclosing attempts and the automatic reclosing function is blocked until the pickup and operate indica-
tions causing the evolving fault disappear.
•
Parameter
Response to evolv. faults
=
strt. evol.flt.dead time
As soon as an evolving fault is recognized, an automatic reclosing cycle for 3-pole interruption is
switched to. The automatic reclosing function does not allow any 1-pole tripping until the fault is solved
or there is a final switch off; thus, every following trip command will be 3-pole. When the evolving fault is
fixed, the separate dead time for faults will start, see also chapter Dead time. The further process is as by
3-pole cycles.
[dwbspffe-100611-01.tif, 1, en_US]
Figure 7-43 Cyclic Automatic Reclosing Function - Example for an Evolving Fault
7.2.4.13
Protection and Automation Functions
7.2 Automatic Reclosing Function
564 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017