Siemens SIPROTEC 4 7VK61 Manual page 162

Functions
2.9 Auxiliary Functions
[beispiel-grundb-4-zeil-disp-wlk-210802, 1, en_GB]
Figure 2-73
Default display 3 shows the measured power values and the measured values U
[grundb-3-4-zeil-displ-wlk-230802, 1, en_GB]
Figure 2-74
Moreover, the device has several event buffers for operational indications, fault indications, switching statis-
tics, etc., which are protected against loss of auxiliary supply by means of a backup battery. These indications
can be displayed on the LCD at any time by selection using the keypad or transferred to a personal computer
via the serial service or operator interface. Reading out indications during operation is described in detail in
the SIPROTEC 4 System Description.
After a system fault, for example, important information about the progression of the fault can be retrieved,
such as the pickup of a protection stage or the initiation of a trip signal. The system clock accurately provides
the absolute time when the fault first occurred. The fault progression is output with a relative time referred to
the instant of pickup so that the time until tripping and until reset of the trip command can be recognized. The
resolution of the time information is 1 ms.
With a PC and the DIGSI protection data processing software, it is also possible to retrieve and display the
events with the convenience of visualisation on a monitor and a menu-guided dialog. The data can either be
printed out or stored elsewhere for later evaluation.
The protection device stores the messages of the last eight system faults; in the event of a ninth fault, the
oldest is erased.
A system fault starts with the detection of the fault by the fault detection of any protection function and ends
with the reset of the fault detection of the last protection function or after the expiry of the auto-reclose
reclaim time, so that several unsuccessful reclose cycles are also stored cohesively. Accordingly a system fault
may contain several individual fault events (from fault detection up to reset of fault detection).
Information to a Control Centre
If the device has a serial system interface, stored information may additionally be transferred via this interface
to a central control and storage device. Transmission is possible via different transmission protocols.
You may test whether the indications are transmitted correctly with DIGSI.
Also the information transmitted to the control centre can be influenced during operation or tests. The IEC
60870-5-103 protocol allows to identify all indications and measured values transferred to the central control
system with an added indication "test mode" while the device is being tested on site (test mode). This identifi-
cation prevents the indications from being incorrectly interpreted as resulting from an actual power system
disturbance or event. Alternatively, you may disable the transmission of indications to the system interface
during tests "Transmission Block").
To influence information at the system interface during test mode ("test mode" and "transmission block"), a
CFC logic is required. Default settings already include this logic (see Appendix).
The SIPROTEC 4 System Description describes in detail how to activate and deactivate test mode and blocked
data transmission.
Classification of Indications
Indications are classified as follows:
162
Operational measured values in the default display
Operational measured values in the default display
and Ι dargestellt.
L1-L2 L2
SIPROTEC 4, 7VK61, Manual
C53000-G1176-C159-5, Edition 05.2018