Page 488 - IRSEM_Main Book

(e) In Non-route setting type installations, after setting of the route by
individual operation of points is completed, signal can be cleared by an
individual push button in conjunction with a group button or by an
individual switch controlling each signal or a common switch for
conflicting signals which are not required at the same time, or one push
button at the entrance and other at the exit end.

(f) Individual push button in conjunction with a common push button or two/three
position switches shall be provided for individual operation of points.

(g) Where a route has more than one overlap, it shall be possible to select
and set the desired overlap beyond the exit signal of the route.

(h) Where the route has alternate approach routes, it shall be possible to
select and set the desired route with desired overlap.

(i) The switches/buttons shall have distinctive colours so that they can be
readily distinguished, such as running signal red, shunt signal yellow,
calling on signal red with white dot & exit button white. The alternate
overlap white with black dot, alternate route Grey, point black, slot green,
crank handle blue and point group button black with red dot etc.

21.1.3 The control panel shall be provided with:

(a) Arrangement for individual operation of points.

(b) For emergency operation of points (where provided, during point zone track
circuit failures), each individual operation shall be recorded on a counter.

(c) Necessary slotting facilities for adjoining cabins, ground-frames, level
crossings and crank handles etc.

(d) Arrangement so that slot shall be controlled by operation of two buttons
or a switch similar to route setting principle for individual line. For
cancellation of slot, a group slot cancellation button to be operated along
with entrance/exit button shall be provided. Each such cancellation shall
withdraw the slot but the route controlled by the slot shall be kept held for
a predetermined time delay or till route locking if any, is effective. Each
slot cancellation shall be recorded in a counter.

(e) When SM's key is taken out, it shall not be possible to change the last
operated position of any signalling gear from control panel. However,
facility shall be provided to put back the signal to 'ON' position without
altering the route. It shall be ensured that no command gets executed
automatically on reinsertion of SM's key.

(f) An indication panel shall be provided in major yards, giving position of the
yard and important indications for maintenance staff.

21.1.4 Indications on Control Panel

The control panel shall be provided with the following indications.

Chapter 21: Relay & Electronic Interlocking Page 434 of 535