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2.4.2 Self-reset 2.5s delayed reset
The operate circuit is terminated to case terminals 25(+), 27(+), 28(-). Disconnect
external wiring from these terminals to allow application of the test supply.
With the relay reset check the continuity of the closed contacts (shown as break
contacts on the drawing).
Check operation of operate circuit by energising the relay with 60% of the lower
nominal supply voltage.
The relays should switch cleanly with one movement.
Check the operating time of the relay at 100% lower nominal supply voltage and
check the continuity of the closed contacts (shown as make contacts on the
drawing).
Check the delayed reset time by energising the relay with full rated supply volts to
case terminations 25(+), 27(+), 28(-), then remove energisation from the case
termination 27(+). Time the closure of a normally closed contact from this point in
time. The reset time shall be between 2 - 2.8s.
2.5 Restoration of wiring
Restore any external wiring connections that may have been disturbed during the
above tests.
2.6 Problem analysis
Repeat Section 2.2 with particular attention to the connection of external links.
If the relay is found to be faulty it should be returned to AREVA T&D for repair and
recalibration. There are no user serviceable parts inside.
Section 3. MAINTENANCE
Periodic maintenance is not necessary, however routine testing should be carried
out the meet the customer requirements.
Check the relay for operation at 60% lower nominal supply voltage and for
contact wear. If required, the mechanical settings may be checked against those
shown in Section 4.
Section 4. MECHANICAL SETTINGS
4.1 General
Contacts are set at the factory and should not require adjustment.
If contacts show signs of contamination during maintenance it may be necessary to
clean contacts and check settings.
Contacts must be checked by qualified personnel only to
ensure that settings are not disturbed.
The safety section should be read before attempting any adjustments.
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