Tripping Logic Of The Entire Device - Siemens Siprotec 7VK61 Manual

Spontaneous indications
Spontaneous indications are fault indications which appear in the display automatically following a general fault
detection or trip command of the device. For the 7VK61, these indications include:
„Relay PICKUP":
„S/E/F TRIP":
„PU Time":
„TRIP Time":

2.8.1.5 Tripping Logic of the Entire Device

General Trip
All trip signals for the protective functions are connected by OR and generate the message „Relay TRIP".
This can be allocated to LED or output relay.
Terminating the Trip Signal
Once a trip command is initiated, it is phase segregatedly latched (in the event of three-pole tripping for each
of the three poles) (refer to Figure 2-62). At the same time, the minimum trip command duration TMin TRIP
CMD is started. This ensures that the trip command is output to the circuit breaker for a sufficiently long time
even if the tripping protective function resets very rapidly. The trip commands can only be reset after all tripping
protective functions have dropped out and after the minimum trip command duration has elapsed.
A further condition for the reset of the trip command is that the circuit breaker has opened, in the event of single-
pole tripping the relevant circuit breaker pole. In the function control of the device, this is checked by means of
the circuit breaker position feedback (Section „Detection of the Circuit Breaker Position") and the flow of cur-
rent. In address 1130, the residual current PoleOpenCurrent is set which is certainly undershot when the
circuit breaker pole is open. Address 1135 Reset Trip CMD determines under which conditions a trip
command is reset. If CurrentOpenPole is set, the trip command is reset as soon as the current disappears.
It is important that the value set in address 1130 PoleOpenCurrent (see above) is undershot. If Current
AND CB is set, the circuit breaker auxiliary contact must send a message that the circuit breaker is open. It is
a prerequisite for this setting that the position of the auxiliary contact is allocated via a binary input. If this ad-
ditional condition is not required for resetting the trip command (e.g. if test sockets are used for protection test-
ing), it can be switched off with the setting Pickup Reset.
If the 7VK61 relay is operated without current transformer connection, the setting1135 Reset Trip CMD =
CurrentOpenPole, termination of the trip command is only determined by the minimum trip time (TMin TRIP
CMD). If the setting is Reset Trip CMD = Current AND CB, the trip command will be terminated by the
auxiliary contacts of the circuit breaker.
SIPROTEC, 7VK61, Manual
C53000-G1176-C159-3, Release date 05.2009
protective function that picked up;
protective function which tripped (only device with graphical display);
Operating time from the general pickup to the dropout of the device, in ms;
the operating time from general pickup to the first trip command of the
device, in ms;
Functions
2.8 Function Control
157