Type B Vital Relays - Alstom

Theory of Operation
2.5. DC SPECIAL PURPOSE RELAYS
2.5.1. Highway Crossing Signal Flasher Relay
The electronically driven highway crossing flasher consists of a Type B1 neutral relay
and a solid-state flasher module. The flasher module, attached to energy terminals on
the back of the relays plugboard, establishes and maintains a flashing rate of 48 to 54
flashes per minute (fpm) for highway crossing signals or 56 to 64 fpm for flashing
wayside signal aspects. The drawing number of the flasher module determines the flash
rate. Wiring is shown by Figure 2–26.
(FRONT VIEW)
16
26
36
15
25
35
14
13
12
24
23
22
34
33
32
THICK WIRING IS PLUGBOARD WIRING.
THIN WIRING IS RELAY WIRING.
I ="IN" LEAD
O = "OUT" LEAD
11
21
31
I
O
3C
3D
R+
-
+
1E
3E
(-) (+)
Figure 2–26. Electronically-Driven Flasher Relay Wiring
The flasher module drives the Type B1 neutral relay that has four dependent front-back,
heavy-duty, lamp-control contacts. Full back contact pressure is maintained while the
relay is not operating.
P1457, Rev. Nov/07 2–29 Alstom Signaling Inc.