ABB RELION REX640 Technical Manual page 583

1MRS759142 C
REX640
Technical Manual
Therefore, before testing, check that the available terminal diagram
corresponds to the protection relay.
The circuit diagrams of the application are recommended to be available. These are
required for checking the terminal block numbers of the current, trip, alarm and
possibly other auxiliary circuits.
The technical and application manuals contain application and functionality
summaries, function blocks, logic diagrams, input and output signals, setting
parameters and technical data sorted per function.
The minimum requirement for a secondary current injection test device is the ability
to work as a one phase current source.
The protection relay should be prepared for the test before testing a particular
function. The logic diagram of the tested protection function must be considered while
performing the test. All included functions in the protection relay are tested according
to the corresponding test instructions in this chapter. The functions can be tested in any
order according to user preferences. Therefore, the test instructions are presented in
alphabetical order. Only the functions that are in use (Operation is set to "on") should
be tested.
The response from the test can be viewed in different ways.
• Binary output signals
• Monitored data values in the LHMI (logical signals)
• A PC with a Web browser for WHMI use (logical signals and phasors)
All used setting groups should be tested.
Checking of the external optical and electrical connections
The user must check the installation to verify that the protection relay is connected to
the other required parts of the protection system. The protection relay and all the
connected circuits are to be de-energized during the check-up.
Checking of CT circuits
Check that the wiring is in strict accordance with the supplied
connection diagram.
The CTs must be connected in accordance with the terminal diagram provided with
the protection relay, both with regards to phases and polarity. The following tests are
recommended for every primary CT or CT core connected to the protection relay.
• Primary injection test to verify the current ratio of the CT, the correct wiring up
to the protection relay and correct phase sequence connection (that is L1, L2, L3.)
• Polarity check to prove that the predicted direction of the secondary current flow
is correct for a given direction of the primary current flow. This is an essential test
Section 4
Protection functions
577