Siemens SWT-3000, Руководство по эксплуатации оборудования

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Command Loop Test
Command loop test provides a function to measure the command transmission time without using any other
test equipment, and there is no need to activate a real command input/output. It can be used for stand-alone
SWT3000 and SWT3000 integrated in PowerLink.
It is only activated in the current transmission line, if a redundant transmission line is configured.
If a command loop test is triggered, a test signal is generated inside PU4 and sent to the remote side over the
command transmission path. At the remote side, the test signal is reflected. One-trip delay is calculated at the
local side when receiving the reflected signal.
Note that, the measured time does not include the delay taken from input/output interface of IFC or EN100
module, so there is a gap between the end to end command transmission delay and the measured delay. The
interface delays are list in below table.
Interface Additional delay(ms)
IFC-P 1.2
IFC-D 5.2
GOOSE 1.9
The end to end delay = measured delay + interface delay.
The measured delay can be viewed in PowerSys > Information > Counter. The value is between 0 ms ~25.5
ms. 0 means that the test is not available, while 25.5 ms means that the line is broken.
Command loop test can be executed in two ways. One is the periodic loop test, that can only be enabled in
digital transmission line. It is triggered automatically at a configurable interval. The test result (OK/fail) is
recorded in event log.
Another is the single test, it is triggered manually by PowerSys test command.
2.17
Functional Description
2.17 Command Loop Test
96 Smart Communication, SWT 3000 Teleprotection, Equipment Manual
C53000-G6040-C605-1, Edition 03.2020