Siemens siprotec 7SA522, Руководство пользователя

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Configuration
5-4
7SA522 Manual
C53000-G1176-C119-2
overcurrent protection (DT), an inverse time overcurrent protection can be configured
to either correspond to the IEC characteristics (
72&,(&
), or to the ANSI characteris-
tics (
72&$16,
). The various characteristics are shown in the technical data. The time
delayed overcurrent protection may naturally also be disabled (
'LVDEOHG
).
The tripping characteristic of the earth fault protection can also be selected, in this
case in address
(DUWKIDXOWRYHUFXUUHQW(DUWK)DXOW2&
. In ad-
dition to the definite time overcurrent stages (DT, up to three stages can be implement-
ed), it is also possible to configure an inverse earth fault stage. This inverse stage may
either correspond to the IEC characteristic (
72&,(&
) or to the ANSI characteristic
(
72&$16,
), or to an inverse logarithmic characteristic (
72&/RJDULWKP
). If an in-
verse tripping stage is not required, the stage that is usually referred to as “inverse”
may also be used as a fourth definite time stage
'HILQLWH7LPH
. The various char-
acteristics are shown in the technical data. The earth fault protection may naturally
also be disabled (
'LVDEOHG
).
If the device has an automatic reclosure, the addresses and are signifi-
cant. If no reclosure is desired at the feeder for which 7SA522 is used or only an ex-
ternal device is used for reclosure, address
$8725(&/26(
is switched to
'LV
DEOHG
. Automatic reclosure is only permitted for overhead lines. It may not be used
in any other case. If the protected object consists of a combination of overhead lines
and other equipment (e.g. overhead line in a block with a transformer or overheadline/
cable), reclosure is only permissible if it can be ensured that it can only take place in
the event of a fault on the overhead line.
Otherwise set the number of desired reclosure attempts there. You can select
$5 F\FOH
to
$5F\FOHV
. You can also set
$'7
(adaptive dead time): in this
case the behavior of the automatic reclosure depends on the cycles of the remote end.
However, the number of cycles must be set at least at one end of the line and this end
must have a reliable infeed. The other end or ends may operate with adaptive dead
time. See section 6.11.1 for detailed explanations.
The
$5&21752/02'(
under address allows a total of four options. You can
determine whether the sequence of automatic reclosure cycles is defined by the fault
situation of the pick-up of the starting protection function(s) or by the type of trip com-
mand. The automatic reclosure can also operate with or without action time.
The
7ULS ZLWK7DFWLRQ
or
7ULS ZLWKRXW7DFWLRQ
command setting is pre-
ferred when single-pole or single/three-pole automatic reclosure cycles are planned
and are possible. In this case different dead times (for every interrupt cycle) are pos-
sible after single-pole tripping and after three-pole tripping. The tripping protection
function determines the type of tripping: single-pole or three-pole. The dead time is
controlled dependent on this.
Using the
3LFNXSZLWK 7DFWLRQ
or
3LFNXSZLWKRXW 7DFWLRQ
setting, dif-
ferent dead times can be set for the auto-reclosure cycles after single, two and three-
phase faults. The fault detection configuration of the protection functions at the time
the trip command disappears is decisive. This operating mode also enables the dead
times to be made dependent on the type of fault for three-pole interrupt cycles. Trip-
ping is always three-pole.
The
7ULS ZLWK7DFWLRQ
setting provides an action time for every interrupt cycle.
This is started by the general starting signal (i. e. logic OR combination of all internal
and external start signals of all protection functions which are configured to start the
automatic reclosure function. If there is still no trip command when the action time ex-
pired, the corresponding automatic reclosure cycle cannot be executed. See section
6.11.1 for further explanations. For the time graded protection this setting is recom-
mended. If the protection function to operate with reclosure does not have a general