Type B Vital Relays - Alstom

Preventive Maintenance
4.5.4. Code-Responsive Relay Test
To obtain operating values for the code-responsive relay follow the procedure in
Table 4–10.
Table 4–10. Code-Responsive Relay Test Procedure
Step
Procedure
1 Perform the visual inspection procedure in Table 4–5.
2 Saturate relay coils at current value specified on specific ED sheet.
3 Operate relay several times by opening and closing circuit.
4 Slowly reduce current to obtain DROPAWAY value. Two readings of
DROPAWAY values should be taken, one to close back contacts and the other
to allow the armature to touch its backstop pin.
5 Open the circuit, close the circuit, and then slowly increase the current to obtain
PICKUP and WORKING values. PICKUP is the current value at which the front
contacts just close. WORKING is the current value at which the armature in the
fully energized position is up against the stop.
P1457, Rev. Nov/07 4–14 Alstom Signaling Inc.