Type B Vital Relays - Alstom

Corrective Maintenance
6.5.3. Microchron II Timer Relay Electronics Removal and Replacement
Before performing tests on the relay portion of the Microchron II Timer Relay, the timer
electronics must be removed from the relay structure. The timer electronics if referred to
as the Motherboard for the DC version of the relay, and the Timer board for the AC
version.
NOTE
The location of the timer electronics is on the left side of the relay as you
face the front of the DC version of the relay and on the right side of the
relay as you face the front of the AC version of the relay.
Perform the procedures in the sequence provided.
WARNING
BREAKING THE RELAY COVER SEAL VOIDS THE WARRANTY ON
THE RELAY.
P1457, Rev. Nov/07 6–23 Alstom Signaling Inc.