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Varieties of signals

Main Multiple aspect colour light signal controlled foreach occasion of use by a signaller.

To pass signal at danger requiresthe driver to be given a paperauthority

Semi-auto A main signal which the signaller can set to work

automatically.

[Equivalent to a signal with an

Auto Working Facility or fleetingfunctionality; a UK semiauto iscom!letely "ifferent#$

Shunt aspect !"n#"ff$ %osition &ight'ed # (hite # )ellow

*river may proceed at no more than +,kph forthe purposes of making a shunting movementinto what may be an occupied section.

alling-on Miniature yellow additional lamp. enerallyprovided on the /ome signals provided within astation area0 not on the starting signal givingauthority to move into the ne1t block section.

Also may not be provided on2ormally out3 illuminated if signal may bepassed0 driver must be prepared to stop prior toany obstruction. an be used in normal traffic toadmit a train into the station whencircumstances do not permit the main signal4saspect to be cleared0 also used as a form ofdegraded mode working when the main signal isunable to clear due to a fault.

[%ore like the UK &'(A than theUK callingon; however note thatin the UK a "river may )e ver)allyauthorise" to !ass a signal at

"anger whereas in *n"ia it requiresa han"signaller at the signal tohan" the relevant form to the"river an" hence the nee" forthem is greater$+

Auto Signal not operated from a station signalbo1

There are no points or level crossings etc in theroute.

A driver may pass such a signal atdanger on their own authority afterhaving waited minutes0

ate A signal that protects a level crossing andoperated from a gate-bo13 but would otherwisehave been an auto signal.

To pass signal at danger requiresthe authority of the local operator[)roa"ly )ut not e,actly equivalentto the UK semiauto$

%ermissive "ne which does not display a stop aspect3 but is5ust a distant signal

[-otally "ifferent meaning to theUK where the term means theauthorisation of a secon" .ormore/ train to enter an alrea"yoccu!ie" )lock section0 generallyfor the !ur!oses of cou!ling u!$+

oods A signal that is provided for movements intoyards and other non-passenger railway.

%assenger trains are not permitted to take theroute.

6ntermediate7lock Signal

Acts as the section signal for the absolute blockto the ne1t signalbo13 but located far beyond itscontrolling signal bo1.

A driver may pass such a signal atdanger on their own authority afterhaving waited , minutes0

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Aspects

Aspect Meaning omment

'ed Stop here

)ellow aution3 stop at ne1t stop signal.

*o not necessarily need to startor continue braking0 this is for thedriver to determine according totheir 8section learning9.

2.7. There is no guarantee that there isbraking to the ne1t signal from the yellowaspect

*ouble )ellow aution3 approaching a stopsignal but it is not the ne1t one.

*o not necessarily need to startor continue braking0 this is for thedriver to determine according totheir 8section learning9.

2.7. The first cautionary aspect encounteredby a driver is guaranteed to give brakingdistance to the red0 however there can be anynumber of further signals also displayingdouble yellow prior to the single yellow beforethe red aspect.

reen :nrestrictive aspect

"verlaps

Signal "#& +;m for < or = aspect signals

>>>> for aspect signal #semaphore

7lock "#& =;;m in semaphore areas

+?;m where a < aspect colourlight in rear

An overlap can be shorter thanthis if directed into a sand-humpproviding the stopping ability iscomparable it can be as short as

@;m or even less.

quivalent to 7lock clearing point0 thedistance beyond the acceptance home whichmust be clear prior to the signaller being ableto give a 8&ine lear9 to permit entry of a traininto the block section from the signalbo1 !oethe 67 signal$ in rear

2ote that in block working3 shunting is permitted within the station area potentially up as far as theadvanced starter but at certain sites can be limited by the presence of a facing &imit of Shunt boardBnot UK !racticeC. Shunting back signals are provided.

ssentials of 7lock (orking

"nly one train at a time within a single block section

Signaller must obtain a &ine lear from the ne1t signal bo1 prior to clearing their advanced

starter

A &ine lear may only be given when both the block and the block overlap are clear of all

trains and other obstructions

The arrival of a complete train is determined byD

a$ proving by a1le counter clear !where provided$3b$ observation of the &V board !&ast Vehicle$- EEquivalent to tail lam! in the UKCc$ determined clear after having made a shunting movement.

The capacity of a length of line is constrained by the section that takes the longest to traverse0 this isknown as the 8ruling section9. apacity can be increased by providing track circuits between theAdvanced starter and an additional signal situated mid section3 known as the 67S F 6ntermediate7lock Signal. This creates another block section3 that is totally under control of the rear signalbo1 andthe 67S is the entrance signal of the shortened block section to the bo1 in advance and is the section

signal released by its &ine lear. The 67S has its own permissive signal braking distance prior to it.

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"peration in *egraded Mode

%& F 8%aper &ine lear9. Gey personnel have pre-printed books similar to raffle tickets that areprinted with a random sequence of 8private numbers90 these communicate by block telephone andinclude the e1change of these private numbers which are then recorded as a proof that can be usedlater in any dispute that the messages were from the relevant person.

"n S 7lock for double lines a non-cooperative release is implemented. The receiving station turnsa handle to change the block status from train on &ine to &ine losed !the 2ormal status of a block$.

"n S 7lock for single lines a cooperative release is implemented0 this requires a sequence ofoperations involving both the transmitting station and the receiving station. *epending upon whetherit is a token system or tokenless block operation is slightly different but in either case a relay pickswhich bypasses the normal locking controls.

(here there is continuous track circuiting3 operation will be by 7( F Auto 7lock (orking

lements of 6nterlocking0

Hor a signal to be cleared

+ %oints in isolation Bequivalent in UK terms as !rovi"ing flank or tra!!ingC3 route or overlap arerequired to be set and locked3 e1cept that trailing points in the overlap are required to be set butnot locked !does this make sense- wonder if there is a confusion between locking and detectionhere....$

&evel crossing closed to road vehicles

< All track circuits !if appropriate for the type of signal$ clear between entrance signal and the end

of the overlap beyond the following signal or the end of the block overlap if applicable.

B*t seems as if *n"ia often uses an a,le counter section to reinforce the integrity even thougha)solute )lock working is retaine" over the )lock section C