GK/Rt0044 - Provision & use of facilities

[savitha kandasamy]

Hi members,
In GK/RT0044 , sec 4.1.2 has the following wordings.

"At each location where facilities are provided to signal trains onto Occupied Lines, the Infrastructure Controller shall specify and document the particular purposes for which those facilities are permitted to be used, and shall ensure that they are not used for any other purpose."

In this i am not able to understand about the facilities & what it is referring for. Is it referring to the signalling equipments?. Also why the facilities are not used for other purposes?. Kindly clarify.

[NJK]

In Indian Railways, we have calling on signal movement. Normally calling on signal provided below the main signal. Whenever main signal fails to clear for the following reason, signaller will give calling on signal route.

a. Main signal is not showing off aspect because of signal in advance is blank.
b. Main signal all off aspect are (Lamp) failure.
c. Main signal route indicator is failure.
d.Overlap point is failure to operate.
e. Signal control track circuit is / are failure.

In this condition signaller will give Calling on Signal route. In Interlocking logic also we are providing calling on counter. Whenever calling on signal given, calling on counter will get increment one.

So the signaller will register the calling on signal clearance purpose with calling on counter number and the reason.

Regards,
NJK

Hi members,
In GK/RT0044 , sec 4.1.2 has the following wordings.

"At each location where facilities are provided to signal trains onto Occupied Lines, the Infrastructure Controller shall specify and document the particular purposes for which those facilities are permitted to be used, and shall ensure that they are not used for any other purpose."

In this i am not able to understand about the facilities & what it is referring for. Is it referring to the signalling equipments?. Also why the facilities are not used for other purposes?. Kindly clarify.

[PJW]

Note that in the UK, "calling-on" means different to India.
It is a Position Light aspect which permits a passenger train to enter a section of line KNOWN ALREADY TO BE OCCUPIED by another passenger train. Obviously this is not widely used; we of course generally signal the railway on ABSOLUTE (i.e. only 1 train oper section of line at any one time) rather than PERMISSIVE (more than one train) principles. However in UK it is nothing to do with failures; permissive moves are used when operationally needed in normal circumstances.

This can be
a) because the two trains need to join up. For example at Redhill there can be one train from Reigate and annother from Tonbridge timetable to arrive within a few minutes of each other, join up and then proceed as one longer train all the way to London. This saves drivers and even more importantly "train paths" and thus gives grerater capacity during the peak rush hour.
b) because there are simply not enough platforms at the station- there are few but long platform faces and multiple trains. Lincoln is an example; I have seen three separate 2 car trains placed at intervals along the same platform, all to / from different destinations. Passengers can of course intercahnage without needing to go up/down steps, but primary reason is that station layout does not have the width needed for lots of parallel platforms.

In perhaps the last 20 years, the risks of such use are no longer regarded as slight, so there is the aspiration to eliminate such utilisation whenever possible. Whereas a) obviously has to be permitted to get the corresponding advantage of turning 2 trains into 1 longer one, scenario b) is less justifiable. Even if the platform is used in such a manner, there can be intermediate signals spaced alog the platform.
Hence the reason for the wording; the infrastructure manager must be very clear WHY the permissive facility is being provided and be able to justify its provision / retention.

In Indian Railways, we have calling on signal movement. Normally calling on signal provided below the main signal. Whenever main signal fails to clear for the following reason, signaller will give calling on signal route.

a. Main signal is not showing off aspect because of signal in advance is blank.
b. Main signal all off aspect are (Lamp) failure.
c. Main signal route indicator is failure.
d.Overlap point is failure to operate.
e. Signal control track circuit is / are failure.

In this condition signaller will give Calling on Signal route. In Interlocking logic also we are providing calling on counter. Whenever calling on signal given, calling on counter will get increment one.

So the signaller will register the calling on signal clearance purpose with calling on counter number and the reason.

Regards,
NJK

Hi members,
In GK/RT0044 , sec 4.1.2 has the following wordings.

"At each location where facilities are provided to signal trains onto Occupied Lines, the Infrastructure Controller shall specify and document the particular purposes for which those facilities are permitted to be used, and shall ensure that they are not used for any other purpose."

In this i am not able to understand about the facilities & what it is referring for. Is it referring to the signalling equipments?. Also why the facilities are not used for other purposes?. Kindly clarify.

[khalid]

Signaller will give calling on signal route:
a. Main signal is not showing off aspect because of signal in advance is blank.
b. Main signal all off aspect are (Lamp) failure.
c. Main signal route indicator is failure.
d.Overlap point is failure to operate.
e. Signal control track circuit is / are failure.
In this condition signaller will give Calling on Signal route.

Note that in the UK, "calling-on" means different to India.
It is a Position Light aspect which permits a passenger train to enter a section of line KNOWN ALREADY TO BE OCCUPIED by another passenger train. Obviously this is not widely used; we of course generally signal the railway on ABSOLUTE (i.e. only 1 train oper section of line at any one time) rather than PERMISSIVE (more than one train) principles. However in UK it is nothing to do with failures; permissive moves are used when operationally needed in normal circumstances.

I think Mr.NJK has incompletely presented the case for the calling-on signal on the Indian Railways.While it is true that it can be used under conditions of failure outlined by him,its major purpose is also to permit the reception of a train into an occupied line such as while attaching an engine to a train already standing in the platform.Another important purpose is to enable the clearance of the calling-on when sufficient overlap is not available due to a conflicting movement(rather than a points failure)in the overlap portion.
It should also be noted that routinely,reception of a train into an occupied line is actively discouraged unless it is an emergency.
Drivers are instructed to ensure that when they get the calling-on they must not exceed a speed of 15 KMPH and may proceed even more slowly if visibility is poor or while negotiating curved tracks.

Khalid.