Page 489 - IRSEM_Main Book

(a) Point Indications

(i) The position of points shall be indicated either by white/yellow or
green lights near each individual point switch and by white strip light
on the point zone and by white strip light on the point zone in case of
push button. During operation of the points, light/strip light for the
intended position shall flash till points are correctly set and locked.
(ii) The point locked indication in route shall be given by illumination of a
small white light near the point or points switch/button which shall be
extinguished when point is free.
(b) Route Indications

(i) Route indication lamps shall be provided to indicate setting and
locking of the route. Indication that route is set and locked shall be
given by a set of white lights (not less than two) on each track section.
When any route is not set, route indicator lamps shall be extinguished.
(ii) The complete route over which the movement is to take place shall be
lit with a row of white lights when the route is correctly set and locked.

(iii) As the train moves over the route, the portion of the route occupied
shall change to red and after the train has cleared the particular track,
it should change back to white lights until the sectional route/entire
route is released, when the white light is extinguished.

(c) Signal Indications

(i) Indication that a stop signal is at 'ON' shall be given by a red light and
a permissive signal is at 'ON' shall be given by a yellow light on the
corresponding signal symbols on the control panel.

(ii) Indication that stop/permissive signal is 'OFF' shall be given normally
by a green, yellow or double yellow light as signal is seen in the field,
on the corresponding signal symbol on the control panel. In case of
signal ‘OFF’ aspect failed to lit at site, the corresponding signal
aspect indication on the control panel shall be indicated with flashing.
However, in case of a domino panel where indication of all aspects is
not provided, any 'OFF' aspect can be shown by green along with the
following flashing indications for conditions as enumerated below:

 Failure of green; green flashes red* blank;

 Failure of yellow; green flashes, red lit;

 Failure of double yellow, both green and red* flash; &
 Failure of red*, green not lit (blank), red* flashing.

*To be read as yellow for a permissive signal.

(iii) Signal indication for the 'ON' aspect of a shunt signal on the same
post as the running signal, is not required. In the case of shunt signal
on independent post, the 'ON' indication shall be given by a white
light strip or two miniature white lights in a horizontal position on the
corresponding shunt signal symbol on the control panel.

Chapter 21: Relay & Electronic Interlocking Page 435 of 535