Siemens siprotec 7SA6, Manual

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Installation and Commissioning
8-72
7SA6 Manual
C53000-G1176-C156-2
In case of a phase-segregated transmission the above-mentioned checks are carried
out for each phase. The correct phase allocation is also to be checked.
The tests must be carried out at both line ends, on a three terminal line at each line
end for each transmission path. Please take note of the last margin heading “Important
for All Schemes”!
Important for All
Schemes If the earth fault protection was disabled for the signal transmission tests, it may be re-
enabled now. If setting parameters were changed for the test (e.g. mode of the echo
function or timers for unambiguous observation of sequences), these must now be re-
set to the prescribed values.
8.3.13.2 Teleprotection with Earth Fault Protection
This section is only relevant if the device is connected to a grounded system and earth
fault protection is applied. The device must therefore be provided with the earth fault
protection function according to its ordering code (position 16 in ordering code: 4 or 5
or 6 or 7). Address
131 Earth Fault O/C
must have been preset during configu-
ration to enable one of the characteristics of this function (according to Section 5.1).
Furthermore, the teleprotection must be used for the earth fault protection (address
0132 Teleprot. E/F
configured to one of the optional methods). If none of this is
the case, this Section 8.3.13.2 is not relevant.
If the signal transmission path for the earth fault protection is the same path that was
already tested in conjunction with the distance protection according to Subsection
8.3.13.1, then this Subsection 8.3.13.2 is also of no consequence and may be omitted.
For the functional check of the earth fault protection signal transmission, the distance
protection should be disabled, to avoid interference of the tests by signals from the dis-
tance protection: address
1201 FCT Distance
=
OFF
.
Directional Com-
parison Schemes Prerequisites:
Teleprotection for Earth fault overcurr. (Teleprot.
E/F)
in address
132
(Section 5.1) must be set to one of the comparison schemes uti-
lizing a release signal, i.e.
Dir.Comp.Pickup
or
Unblocking
; in addition the set-
ting in address
3201
must be set to
FCT Telep. E/F ON
. Naturally, the correspond-
ing send and receive signals must be assigned to the corresponding binary output and
input. For the echo function, the echo signal must be assigned separately to the trans-
mit output.
For more information about the directional comparison schemes see Subsubsection
6.8.1.1 and 6.8.1.2.
A simple check of the signal transmission path from one line end is possible via the
echo function if these release techniques are used. The echo function must be acti-
vated at both line ends i.e. address
2501
must be set to
FCT Weak Infeed
=
ECHO
only
; with the setting
ECHO and TRIP
a trip may result at the line end opposite to
the test location!
An earth fault is simulated in the direction of the line. This may be done with secondary
injection test equipment. As the device at the opposite line end does not pick up, the
echo function comes into effect there, and consequently a trip command is issued at
the line end being tested.
If no trip command appears, the signal transmission path must be checked again, es-
pecially also the assignment of the echo signals to the transmit outputs.