Type B Vital Relays - Alstom

Corrective Maintenance
6.5.1. Relay Structure Inspection
Before performing any adjustments or tests on a relay, the relay structure must be
visually inspected. Section 7, Parts List, provides a comprehensive list and illustrations
for all of the components of the typical B relay. This procedure applies to typical B
relays and Microchron II Timer relays.
Table 6–10. Relay Structure Inspection Procedure
Step
Procedure
1 If any of the following conditions are not met, take note of the problem and
correct it during the mechanical test.
NOTE
This procedure includes correcting identified problems. This
procedure must be followed by relay mechanical and electrical
tests.
2 Check that the relay cover and seal are not cracked, broken or discolored.
3 Break the cover seal and unscrew the knurled nuts.
WARNING
BREAKING THE RELAY COVER SEAL VOIDS THE WARRANTY
ON THE RELAY.
GUIDE ROD
TUBE
4 Remove the two round rubber washers and the cover.
KNURLED
NUTS
P1457, Rev. Nov/07 6–14 Alstom Signaling Inc.