ABB RELION REL670, Руководство по установке и пусконаладке

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Preparing for test Chapter 11
Verifying settings by secondary
injection
2 Preparing for test
2.1 Overview
This section describes how to prepare the IED to verify settings.
If a test switch is included, start preparation by making the necessary connections to the test
switch. This means connecting the test equipment according to a specific and designated IED
terminal diagram. The IED can then be put into test mode in order to facilitate the test of indi-
vidual functions and prevent unwanted operation caused by other functions. The test switch
should then be connected to the IED. The user can also verify the connection and that the analog
input signals are measured and recorded correctly by injecting currents and voltages required by
the specific IED. To make testing even more effective the Protection and Control IED Manager
(PCM600) should be used. The primary tool at your disposal in the PCM600 apart from the Pa-
rameter Setting Tool (PST) is the Disturbance Handling Tool (DHT). The content of reports gen-
erated by the DHT can be determined by the user which makes it more efficient. For example,
the tool may be configured to only show time tagged events and to exclude analog information
and so on. The disturbance report settings could be checked to ensure that indications are correct.
Functions to test, signals and parameter names can be found in the technical reference manual.
2.2 Preparing the connection to the test equipment
The IED can be equipped with a test switch of type RTXP 24. The test switch and its associated
test plug handle (RTXH 24) are a part of the COMBITEST system which provides secure and
convenient testing of the IED.
When the test-plug handle is inserted into the test switch, preparations for testing are automati-
cally carried out in the proper sequence (i.e. blocking of tripping circuits, short circuiting of
CT’s, opening of voltage circuits, making IED terminals available for secondary injection). Ter-
minals 1 and 12 of the test switch are not disconnected as they supply DC power to the protection
IED.
The test-plug handle leads may be connected to any type of test equipment or instrument. When
a number of protection IEDs of the same type are tested, the test-plug handle only needs to be
moved from the test switch of one protection IED to the test switch of the other, without altering
previous connections.
To prevent unwanted tripping when the handle is withdrawn, latches on the handle secure it in
the half withdrawn position. In this position, all voltages and currents are restored and any reen-
ergizing transients are given a chance to decay before the trip circuits are restored. When the
latches are released, the handle can be completely withdrawn from the test switch, restoring the
trip circuits to the protection IED.
If a test switch is not used it is necessary to take measures according to provided circuit dia-
grams.