Siemens siprotec 7SA6 User Manual page 491

Options for
Fault Location
Retrieved
messages
From the
Device Front
7SA6 Manual
C53000-G1176-C133-1
The spontaneous messages can be acknowledged by pressing the
acknowledgment, the default display is shown.
Especially for the fault location there are, except for the display options in the device
®
display and in DIGSI 4, further display options. Their availability depends on the
device version, the configuration (Section 5.1) and the routing (Section 5.2):
• If the device is provided with an BCD output for fault location, the corresponding
binary outputs are allocated and transmitted to a suited display panel with BCD
decoder, the fault location is indicated in per cent (the line length) and can be read
out immediately after the fault ocurred. The numbers have the following
significance:
0 to 195 the calculated fault location in % (line length). If the number exceeds
the 100 % rate, the fault is located outside the protected line in
forward direction;
197 a negative fault location was calculated (the fault is not located in the
protected line, but in reverse direction);
199 overflow (the calculated value is higher than the maximum value (195 %)
that can be transmitted).
• If the device is provided with at least one analog output (0...20 mA) and the fault
location is output via the latter and then transmitted to a suited display panel, the
fault distance can be read out immediately after a fault ocurred.
For each case please take into consideration that the calculated fault distance only
refers to faults in protected lines, in homogeneous lines. In different cases the result
may be falsified considerably, e.g. from intermediate infeed.
The messages for the last eight network faults can be retrieved. The definition of a
network fault is such that the time period from fault detection up to final clearing of the
system fault is considered to be one network fault. If auto-reclosure occurs, then the
network fault ends after the last reclosing shot, which means after a successful or final-
unsuccessful reclosing. Therefore, the entire clearing process, including the reclosing
attempt (or all reclosing attempts), occupies only one trip log buffer. Within a network
fault, several fault events can occur (from the first pick-up of a protective function to
the last drop-out of a protective function). Without auto-reclosing, every fault event is
a network fault.
Altogether up to 600 indications can be stored. Oldest data are erased for newest data
when the buffer is full.
All available indications are displayed and explained in the Appendix. In a specific
case, of course, only the applicable messages appear on the display.
With a device ready for operation, first press the
The first menu item ($QQXQFLDWLRQ) is marked.
key to enter the $1181&,$7,21 sub-menu (see Figure 7-1).
Press the
key, select the sub-menu item Trip Log and move to the Trip Log sub-
Using the
key. The 75,3 /2* selection appears.
menu using the
In this sub-menu, the indications for the last 8 network faults can be selected, again
using the and keys. See the example in Figure 7-7.
Control During Operation
key. After
LED
key. The 0$,1 0(18 appears.
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7-7