beginning of railways122.252.230.113/content/ppt/sig/s11.pdfbeginning of railways at the initial...
TRANSCRIPT
Beginning of Railways
At the initial stage when Railway operations started
There were Locomotives with less speed
1 S11 Ver.1.0
There was less density of Rail and Road Traffic
2 S11 Ver.1.0
There were simple and small yards
3 S11 Ver.1.0
Hence the simple and robust mechanical signaling system was suitable and sufficient to deal with such a traffic
4 S11 Ver.1.0
Modern age developments
• Density of traffic increased
• Busy and complicated yards developed
• High speed locomotives introduced
• Hence advanced signaling systems with more efficiency and failsafe features have replaced the age old mechanical signaling systems although the basic principles of interlocking are retained to ensure safety
5 S11 Ver.1.0
Electrical Signalling
DEVELOPMENT OF SIGNALLING
Electronic Signalling
Mechanical Signalling
Electro-mechanical Signalling
6 S11 Ver.1.0
The slow operating mechanical gears were replaced with fast operating Electrical gears
7 S11 Ver.1.0
All these electrical gears (point machines, signals, gates , relays etc) are interconnected through electrical circuits following the basic principles of interlocking
8 S11 Ver.1.0
But the basic principles of interlocking were not sufficient to ensure safety and reliability with the introduction of new technologies . Hence additional principles of locking were added to the basic principles of interlocking to achieve a more failsafe and reliable system.
All the interlocking circuits are designed based on these principles . A study of these principles is essential for the designer to design interlocking circuits for an installation
9 S11 Ver.1.0
SELECTION CIRCUITS
Using these basic principles of interlocking some basic circuits were designed .
These basic circuits of electric signaling system are known as Selection Circuits.
Each of these Selection Circuits forms a basic circuit of a larger interlocking circuitry and it plays a unique role to fulfill some of the interlocking principles .
Study of these Selection circuits makes it easier to understand , design and analyze the more complex signaling circuits .
10 S11 Ver.1.0
LIST OF SELECTION CIRCUITS
• Indication circuits(for Tracks, Points and Signals etc.) • Signal control circuits • Route indicators circuits • Track locking circuits • Approach locking circuits • Back locking circuits • Sectional route release circuits
11 S11 Ver.1.0
S11 Ver.1.0
• Sequential route release circuits
• Emergency route release circuits
• LC Gate, Siding Point and crank handle control circuits
• Inter cabin slot circuits
SELECTION CIRCUITS
12
BASIS FOR THE DESIGN OF SELECTION CIRCUITS
The selection circuits are designed on the following principles
• Essentials of Interlocking
• Rules of Isolation
13 S11 Ver.1.0
WHAT IS INTERLOCKING ?
GR definition:
“Interlocking” means an arrangement of signals, points and other appliances, operated from a panel or lever frame, so interconnected by mechanical locking or electrical locking or both that their operation must take place in proper sequence to ensure safety;
14 S11 Ver.1.0
ESSENTIALS OF INTERLOCKING
SEM definition(Para 7.82):
Lever frames and other apparatus provided for the operation and control of signals, points, etc., shall be so interlocked and arranged as to comply with the following essentials :—
(i) It shall not be possible to take 'OFF' a running signal, unless all points including isolation are correctly set, all facing points are locked and all interlocked level crossing are closed and locked against public road for the line on which the train will travel including the overlap.
15 S11 Ver.1.0
ESSENTIALS OF INTERLOCKING
(ii) After the signal has been taken ' OFF ' it shall not be possible to move any points or lock bar on the route, including overlap and isolation, nor to release any interlocked gates until the signal is replaced to the ' ON ' position.
(iii) It shall not be possible to take ' OFF ' at the same time, any two fixed signals which can, lead to any conflicting movements.
(iv) Where feasible, points shall be so interlocked as to avoid any conflicting movements
16 S11 Ver.1.0
S11 Ver.1.0
Isolation between
Passenger line Goods line Siding
Passenger line Not Required if speed < 50 Kmph.
Required if speed > 50 Kmph
Required irrespective of speed
Goods lines Required irrespective of speed
Not Required if speed < 50 Kmph Required if speed > 50 Kmph
Desirable
Siding Required irrespective of speed
Desirable
NA
17
Rules for Isolation
S11 Ver.1.0
Means of Isolation
18
S11 Ver.1.0
Circuit
Non Vital Circuit Vital Circuit
Indication Circuit
Bell or Buzzer Circuit
Pt. Circuit
Pt. Det. Circuit
Signal Control Circuit
19
Vital Circuits: Locking, Operating, Detecting and signal control circuits.
Non Vital or secondary circuits: Repeater, Indications, bells & buzzers .
In vital circuits closed circuit principle is followed i.e. the operative part ( Relay/ Lever
lock/Signal/Point) energized through front contacts of relays.
To ensure safety it is necessary to design the circuits with proper attention, due
consideration for simplicity, consistency and economy.
20 S11 Ver.1.0
Signal control circuits
1)Signal Clearance Circuit
2)One signal one movement circuit
3) Semi Automatic signal
4)Route control circuits
5) Inter cabin slot circuits
1 S11 VER 1.0
Signal Clearance circuit
Signal control circuits are designed to fulfil the essentials of interlocking and general rules. Following are the conditions to be fulfilled electrically before clearing a signal i.e. Before energising signal controlling relay (HR)
2 S11 VER 1.0
1.All points concerned are correctly set, and locked wherever required, as detailed below:
For Home signal Points in Route, in Isolation & in overlap.
For Starter signals Points in Route, in Isolation.
For Shunt signals Points in Route (Isolation not mandatory).
For calling-on signal Points in Route & in Isolation
3 S11 VER 1.0
2. Wherever points are operated by point machine it shall be ensured that the crank handle concerned, used for manual operation of point are kept locked. To ensure this, ‘Crank Handle’ is kept locked inside an electrical key transmitter (EKT) or in special relay box (KLCR) meant for it. When crank handle is in and locked, a relay CHLR/KLCR is picked up and proved in HR circuit.
4 S11 VER 1.0
3. All track circuits concerned are clear (a)For Home signal
(i)Track circuits in the route up to next signal and Overlap tracks. (b)For Starter signal
(i)Tracks upto next signal in advance in the route. (c)For Shunt signals
(i)Normally upto next signal (may be main/shunt signal whichever comes first) in the route i.e. tracks in the route excluding berthing tracks. (ii)In big yards, where intermediate shunts are there, the line is clear upto next intermediate shunt signal in advance.
5 S11 VER 1.0
S11 VER 1.0
4. For Calling-on signal in absolute block : To enable clearance of calling on signal in case of failure of main signal above it due to failure of one or more track circuits in route/berthing/overlap. (i) No track circuit in advance need to be proved. (ii) However it shall be possible to clear Calling-on signal only when the train has come to a stop at the foot of the signal. (iii)This is achieved by a pre- determined time delay after train occupies the calling on track circuit provided in rear of the signal.
6
S11 VER 1.0
5.For Calling-on signal in automatic block in approach (i)In case of automatic signalling system, where there is a possibility of the second train coming on calling-on track (passing the automatic signal in rear at ON) the first track ahead of signal is to be proved. (ii) The TSR concerned shall be proved in the calling on signal control circuit to put back calling on signal to ON, the moment the first train passes calling on signal. Advance starter: One track circuit in advance of the signal.
7
6. In case of stations/yards where no track circuit or axle counter is provided on berthing tracks, a line verification box can be used to verify the clearance of the tracks. 7. In case of signals controlled by more than one agency, the slot concerned has been received from other agencies. Separate slots shall be received for main signals and calling on signals.
8 S11 VER 1.0
8.In case of Goods yards where points are locally operated (either from a lever frame or from a ground frame) the points are correctly set by the yard master and a control is given to enable reception or dispatch as the case may be. 9.Conflicting signals are at ON/not taken off :-Though locking of conflicting signals can be achieved by mechanical locking between levers concerned, the controlling relays of conflicting signals are also proved in de-energised condition for further safety.(HR/HHR/DR)
9 S11 VER 1.0
S11 VER 1.0
` 10) The relays proving the Sequential occupation & Clearance of track Ckts. namely UYR’s concerned are proved in de-energized condition to ensure that these are normalized after previous movement.
10
S11 VER 1.0
11) If Signals are provided with Junction type route indicators : a) The route indicator is not lit for main line. This is proved by
UECR and the controlling relays of Route indicators (UR’s /UCR’s/UHR’s) are in de-energized condition
a) The route indicator is lit with adequate ( Minimum 3) number
of lamps for the loop line concerned. This is achieved by proving the concerned controlling relay & UECR are in the energized condition.
11
S11 VER 1.0
12) Incase of Last stop Signal (LSS), the line clear condition shall be proved to ensure that the proper line clear has been obtained in addition to SM’s Control if any. 13) In case of Interlocked LC Gate, if any shall be closed and locked against road traffic .This is achieved by proving LXPR/LCPR in energized condition.
12
S11 VER 1.0
14) Double Cutting Arrangement : Unless Concerned Signal Lever / Switch is reversed Signal Controlling relay (HR/ HHR/DR/UHR’s) should not be energized. ‘R’ Contact of the Concerned Signal lever / Switch is proved on both positive side and on negative side of the relay. So that a single fault cannot cause any Unsafe condition.
13
Double cutting is provided by UCR Up and ASR down
Double Cutting Arrangement
S11 VER 1.0
Cross protection arrangement
15) Cross protection arrangement: In addition to the double cutting arrangement, the concerned Signal control relay or route indicator control relay is provided with a by pass by ‘N’ contact of the Signal Lever for cross protection.
14
S11 VER 1.0
To prove that when a signal is cleared, the signal immediately in advance is not blank
To ensure this, the energized contact of ECR’s of signal immediately in advance is proved in Signal controlling relay of Signal in rear.
HR of Signal in rear is made Slow to Release , to avoid de-energizing, when signal in advance changes its aspects.
If a relay (GECR) is picked up when any one of the aspects of the signal ahead is lit and this relay contact is used in HR circuit of Signal in rear, HR relay need not be made Slow to release.
17) No-signal cancellation is initiated i.e JSLR down.
15
16) Red Lamp Protection:
S11 VER 1.0
Designing of Signal Control Circuit
18) SM’s Key inserted and turned to ensure the authorized operations (SMR/SMCR Up)
16
19) Route Checking relay (UCR) is up 20) One Signal – One train movement (TSR UP) 21)ASR,OVSR and TLSR / TRSR of the signal concerned are to be
proved in dropped condition
S11 VER 1.0
22) Siding in the route and the overlap are kept normal .(Siding KLPR / NPR up ) 23) Signal button is in released condition. ( GNR down) 24) Signal Control relays ( HR,UGR, DR ) are made slow to release.
17
Conditions to be proved in Clearing a Signal (HR )
S11 VER 1.0
Cross protection
The power signalling system mainly depend upon the integrity of the equipments It is require to ensure that such vital equipments do not operate by cross / false feed. To Achieve this, an arrangement called Cross Protection is employed.
19
S11 VER 1.0
Break in cross protection can not be detected
Such arrangements are adopted for Track repeating relays and other vital circuits.
20
Break in cross protection can be detected
S11 VER 1.0
The inoperative line is connected to the return polarity. By this arrangement it is ensured that a false feed connected across the relay is connected to negative thus protecting the relay from operating due to false feed.
Double cutting method
21
TPR CIRCUIT FOR PLUG IN TYPE RELAY
TR TR
TPR
TR
22 S11 VER 1.0
S11 VER 1.0 23
Provide double cutting through the contacts of different relays in both the limbs
24 S11 VER 1.0
B121
ASR
WLR
N121
ASPR
Conflicting signals Conflicting signals are at ON/not taken off :-Though locking of conflicting signals can be achieved by mechanical locking between levers concerned, the controlling relays of conflicting signals are also proved in de-energized condition for further safety.
25 S11 VER 1.0
26 S11 VER 1.0
27 S11 VER 1.0
28 S11 VER 1.0
Shunt Signals Shunt signals are subsidiary signals provided to facilitate shunting movements in the yard. These signals are provided either on a separate post or below a stop signal except First Stop Signal of the station. When a shunt signal is provided on a separate post it displays ON and OFF aspects and when provided below a stop signal it displays OFF aspect only. The following additional points to be observed in locking the conflicting signals in the yard
29 S11 VER 1.0
30 S11 VER 1.0
Yard lay out 1
Dependant Shunt Signal: ReferYard lay out 1
1. Sh 49 Locks opposite home, calling on , advance starter (same
route) and opposite shunt.
2. Sh 49 Locks starter above it.
Note:
1. As shunt signal has no overlap, opposite shunting is permitted. E.g.
Sh41 to Main line and Sh 42 to Loop line.
2. Through shunting is also permitted
31 S11 VER 1.0
S11 VER 1.0
Independent shunt signal:
1. Sh.41 to main line, locks advance starter in rear, home, calling on,
starter opposite and starter in the same direction
2. Sh.43 locks opposite Sh.44 on the route
3. Sh.42 locks the opposite home whose route / overlap falls in the
route of shunt signal
4. Shunt signal has no overlap like calling on signal
32
Shunt locks any signal above it (on the same post) if it is leading on the same route/routes.
5 locks 47 3 locks 49 7 locks 51
33 S11 VER 1.0
S11 VER 1.0
Shunts being subsidiary signals, locks respective main signals
on the same line in same or opposite direction.
(a)41 locks 1
(b) 41 locks C1
(c) 41 locks 2
(d) 41 to Road 1 locks 5
(e) 41 to Road 2 locks 3
(f) 41 to Road 3 locks 7
34
S11 VER 1.0
In Signal Controlling Circuit it is seen that once the train clears the route, the signal can assume OFF aspect on its own, if the signal lever continues to be in ‘Reverse’ position. This feature is undesirable. To ensure One Signal One Movement, a Stick Relay is introduced. The stick relay (LS/SR/TSR) is controlled by the first track circuit immediately in advance of the signal and the normal position of the signal levers concerned. Once energized through normal position of the signal levers concerned, the stick relay holds through its own contact, bye- passing the signal lever contacts
35
One Signal one movement
(Track Stick relay (TSR)/Stick Relay (SR)/ Lock Stick Relay (LSR)
S11 VER 1.0
The TSR drops after the train passes the signal and requires normalization of all signal levers concerned, to pick up again. TSR is made slow to release to prevent it from dropping in the event of bobbing of controlling track circuit after the signal is cleared. If the track circuit repeater relay (TPR) is QSPA1 (which is both slow to pickup and slow to release), then TSR need not be made slow to release
36
S11 VER 1.0 37
38 S11 VER 1.0
S11 VER 1.0
Instead of having individual TSR for each signal in the yard,
wherever possible a common TSR may be provided to reduce
number of relays required in an installation.
Conditions for Common TSR
i) Having common controlling track circuit.
ii) The signals which are of conflicting in nature.
39
Common TSR for more than one Signal
S11 VER 1.0 40
S11 VER 1.0 41
42 S11 VER 1.0
43 S11 VER 1.0
44 S11 VER 1.0
Red Lamp protection
Method 1 :
Method 2:
S11 VER 1.0
SEMI AUTOMATIC SIGNAL
45
A signal, which is capable of being worked as a manual stop signal as well as
an automatic signal, is known as semi automatic signal.
In practice, a manual stop signal is converted in to an auto signal by the
operation of King Lever. King Lever is released by the signal lever concerned.
Already we have discussed about the HR circuit. It can be noted that after the
passage of train, all the selections in HR circuit are available again except TSR
front Contact (assuming signal lever concerned have not been replaced to normal).
If the TSR is made to pick up after the clearance of respective controlling
track by the train, the signal will reclear automatically. This principle is adopted in
converting a manual stop signal into automatic signal.
46 S11 VER 1.0
K.L
NA
1
RE
TSR
TPR1
1
1TSR
1
1T
A
RE
KING LEVER
'A' MARKER RE
KING LEVER
S11 VER 1.0 47
By the operation of King Lever, the signal lever is back locked and the
reverse contact of the King Lever is bridged across the normal contact of signal
lever in TSR Circuit .
King lever can be operated to ‘R’ only when all points are set & locked to
straight route
As soon as the train passes the signal, TSR drops. When the train clears the
controlling track (1T), TSR picks up again through Reverse contact of the king lever,
even though signal lever normal contact is not available.
Signal clears again, when the other track circuits concerned are cleared.
When signalling gear is controlled by more than one agencies/ controllers then that gear is called as slotted gear. When such controlling is achieved through two or more cabins then such controlling is called as inter cabin slotting.
48 S11 VER 1.0
INTER CABIN SLOTTING
49 S11 VER 1.0
When a signal is controlled by more than one agency, consent from other agencies are to be obtained. Each person giving the slot shall ensure; a) Correct setting and locking of points, clearance of track circuit, crank handle
Interlocking (motor points) ,locking of conflicting signals, closing and locking of interlocked LC gates, if any in his zone
b) With given slot only one train can be dealt(one slot one train) c) Separate slots are provided for main &calling on signal as conditions to be satisfied are
different. d) Calling on slot is mainly to lock the conflicting Signals from other side
50 S11 VER 1.0
Inter cabin slotting
S11 VER 1.0 51
In the layout shown in diagram to take OFF home signal No.1, Cabin A requires permission from SM and cabin B, that conditions are favourable to receive the trains with the signal no.1 to the nominated road.
S11 VER 1.0 52
The relay energised in cabin A is called as slot relay (YR) and is controlled by respective lever of cabin B and SM’s slide.
It may also be noted that, for signals leading to more than one route, separate slots must be obtained for each route.
Slot is also required if block instrument is controlled by Station Master and operation of signalling functions controlled by cabin man / lever man. From cabin the signal controlling entry into the block section (last stop signal) shall be taken OFF only after receiving the respective slot from station master.
It should not be possible to take OFF a signal which is slotted by one or more agencies. Visual indication should be provided in the cabin to indicate the receipt of slot. In case of any emergency it should be possible or any operating or any slotting agency to put back the signal to ON position independently Where track circuits are provided i) the concerned slot circuits should prove clearance of track circuit. ii) the occupation of any of these track circuits should replace the signal to ON automatically. Suitable cross protection should be provided against any contact fault or cross feed. When a slotted signal is replaced to ON either by withdrawl of slot or by actuation of track circuit by a train .other signals which are released by the slotted signal should also be replaced to on automatically(Example ;An outer signal should be replaced to ON when the slot for home signal is withdrawn)
53 S11 VER 1.0
Essential Principles of Slotting
ROUTE INDICATORS
1 S11 VER 1.0
S11 VER 1.0
In diverging junctions, each route is provided with a signal in case of semaphore signaling. To avoid number of signals with colour light signaling an Arrangement is adopted in which only one signal is provided with an indicating apparatus known as Route Indicator to work in conjunction with the signal. This Route indicator indicates the line on which the train is signalled by displaying a row of white lights or by displaying illuminated letters or numbers. The various types of Route indicators a)Stencil type route indicator b)Multi lamp route indicator c)Junction type route indicator
2
Directional Route Indicator Multi Lamp Type Stencil type
Route Indicator Route Indicator
S11 VER 1.0 3
Stencil type Route Indicator
• It is provided where trains are expected to stop and proceed
• It consists of a short metal case and divided into number of compartments
• Each compartment is provided with a stencil with letter /figure behind a glass
• Two lamps are provided in the compartment which are connected in parallel for illuminating the stencils
• The visibility of these indicators is very poor ,hence used only for the signals where the trains stop and start (Starters generally)
• Maximum 4 routes can be indicated by this type of route indicators
• M Main line B Branch line G Goods line
4 S11 VER 1.0
Multi Lamp type Route Indicator
• It is provided where more number of routes are required to be displayed • It consists of lamps in a case which are arranged in different rows and columns • They are illuminated in such a manner that they form a numeral or an alphabet. • Type I ( 35 lamps, 7R x 5C , 9 routes ) • Type II ( 49 lamps, 7R X 7C , 19 routes ) • Visibility better than stencil type • It is generally used for Home signals • Lamps are connected in series / parallel • All routes including main line are indicated by a number or an alphabet
5 S11 VER 1.0
S11 VER 1.0
If lamps are connected in series
Advantages;
It becomes very easy for providing lamp proving
arrangements.
Disadvantages;
It requires a special transformer
One lamp fusing will cause disconnection of all
other lamps in the circuit of that route
The circuit becomes complicated
If lamps are connected in parallel
Advantages;
One lamp fusing will not cause disconnection of
lamps in the circuit
Disadvantages;
One or two lamps fusing may give a wrong figure of that route
6
S11 VER 1.0 7
S11 VER 1.0 8
RD.1
22
MAIN LINE
1
BM
23
12
14
RD.2
RD.3
24
MB
102
BRANCH
LINE
3
SIGNAL CONTROL RELAY CIRCUIT WITH STENCIL TYPE OR MULTI LAMP ROUTE INDICATOR
HR
10RWKR
10
NWKR
23
23
RENA
2323
RE
NWKR
12
NWKR
10
RWKR10
HR
23
UHR(M)
UHR(B)
23
23 23
UHE(M)
23HR
BX 110
RWKR
10NWKR
UHE(M)
UHE(B)
UHE(B)
10
23
HR23
NX 110
*
*
* DIRECTLY FED 110V/25W
2 BULBS IN PARLLEL
ONLY IN RE AREAS
NOTE:- UHR(M) & UHR(B) ARE REQUIRED
S11 VER 1.0 9
10
RWKR
RE
2 2
NA RE
2
2
RWKR
12
NWKR14
HR
12
NWKR
14NWKRNWKR
10
NWKR10
NWKR12
12RWKRRWKR
102HR
UHR1
2
2
UHR2
2
UHR3
Junction Type Route Indicator
• It is also known as position light type or direction type route indicator
• It has better visibility .Hence it can be used in high speed junctions.
• It is indicated by a row of 5 white lights pointing towards left or right of the signal.
• It can exhibit a maximum of 3 routes on either side of the main line.
• Fusing of one or two lamps will not give any wrong indication.
• No indication is given when signal is taken off for main line .
• The route indicator units are fixed on the CLS unit .
10 S11 VER 1.0
Junction type Route indicator circuit
• The circuit is so designed that for turn outs the route indicator will glow first and then the signal will assume Off aspect . If the route indicator failed to glow then the signal will not assume Off aspect.
• So for M/Line HR is energized by proving UHR/UR & UECR drop
• For loop lines HR is energized by proving UHR/UR & UECR pickup
• A junction type route indicator unit consists a pilot lamp in the bottom which is commonly lit for all loop lines
• For each loop line a set of 4 white lamps also along with the pilot lamp
• UECR picks up only when 3 route indicator lamps at least glow in the signal including the pilot lamp.
• UECR is common for all loop lines of a signal .
11 S11 VER 1.0
S11 VER 1.0 12
12
1
UECR1 1
UHR3
1
UHR3RE
RWKR
14
12NWKR UECR
1
1
HR
1
1
RENA
11
RE
RD 1
RD 2
RD 314
NWKR14 1
UHR3UHR11
1UHR1
RWKR12
UHR31
RE
1
UHR1
1
UHR11
S11 VER 1.0 13
UG(P)
UG1
UG1
UG1
UG1
UG3
1
1
1
1
UG3
1
UG3
UG3
1UHR1
UHR31
UHR11
UHR31
UHR1UHR311
1PIVOT/PILOT
1
UECR
1
LEVER LOCK AND CIRCUIT CONTROLLER.
S11 VER 1.0
2
In mechanical installations the functions are operated by a lever through a rigid
mechanical means i.e.
— for points by rod transmissions and
— for signals by wire transmission.
In Electro-mechanical installations the functions are operated by mechanical lever
without any rigid connection.
Because of this they may go out of correspondence with lever.
To avoid this condition different electrical locking is required.
This is done by means of “Electrical lever lock”
Electrical lever lock
S11 VER 1.0
3
Lever lock consists of
a) Electromagnet,
b) Force drop device,
c) Economizer contact and
d) Lock proving contact.
•The electrical lever lock can be fixed either vertically or horizontally to the lever inside the cabins • The lock slide is connected to the lever tail and its base is rigidly fixed to a frame . •It allows the lever to operate only when the lock coil is energised and the lock pawl is out of the notch in the slide. •The lock coil is energised only when the conditions for the lever operation are favourable
S11 VER 1.0
4
Electromagnet: Will get energised when supply is received. Force drop device: Some times the armature of the lever lock may not release after de-energisation of lock coil due to residual magnetism or any other mechanical holding. The force drop pins force the lock pawl to drop into the locking notch through its bevel shaped extension before each pick up. Economiser contact: is provided with electric lever lock and circuit controllers to cut off power to the coil at the end of each stroke. It makes between A and E positions of the lever and remains disconnected in N and R positions of the lever. In absence of "Economiser contact" purpose is served by AE band of circuit controller. S11 VER 1.0
5
LOCK
TR
Fig.1.2 ECONOMISER CONTACT
E.C.
S11 VER 1.0
6
Lock proving contacts:
A set of contacts are actuated when the lock is de-energised and lock pawl
drops into the locking notch, proving that the lever is locked positively.
An electrical circuit taken through these proving contact, proves that the
armature is de-energised and consequently the lever is locked.
S11 VER 1.0
7
The lock pawl holds the lever mechanically so that the lever cannot be operated when the
condition for its operation is not safe.
Armature extension (lock pawl) engages in the notch to lock the lever when the electro-magnet
is de-energised. Consequently, the lever cannot be operated till the lever lock coil is energised.
When the armature is attracted and the lock comes out of the notch on the lever slide and
permitting the plunger to move.
S11 VER 1.0
8
Circuit Controllers: Circuit Controller is a device by which electrical circuits can be made or
broken according to requirements.
It has generally got the two sets of fixed contacts and corresponding numbers of rotating
contacts. The rotating contacts may be of different positions such as N,R., NB, RD, etc.
S11 VER 1.0
S11 VER 1.0 9
10 S11 VER 1.0
ELECTRICAL LOCKING ON
POINT AND SIGNAL LEVERS
1 S11 VER 1.0
Necessity for additional locking in Power signaling
Due to the following reasons additional electrical locking is required in power signaling
1) Lock bars are not provided . Hence there is a chance of manipulation of point under wheels
2) There is no rigid connection between control and function .Hence the control and function may go out of correspondence.
3) Operations are very fast .Hence there is a chance of pre mature route release which may endanger an approaching train.
2 S11 VER 1.0
Additional Electrical locking provided on signal and point levers in electromechanical installations
• To prevent the point operation when the point zone is occupied
• To prevent the completion of point lever operation, unless correct correspondence is established between point and point lever.
• To prevent the full normalization of signal lever before the signal is put back to normal at site
• To hold the route in face of an approaching train, until the train comes to a stop at the signal and conditions are safe
• To hold the route ,even though the train has passed the signal ,but is still on the route .
3 S11 VER 1.0
The electrical lockings which are provided to fulfill the above requirements are :
1) TRACK LOCKING
2) INDICATION LOCKING
3) APPROACH LOCKING
4) DEAD APPROACH LOCKING
5) BACK OR ROUTE LOCKING
4 S11 VER 1.0
TRACK LOCKING
Definition: It is an electrical lock on a point mechanism and /or on its connections ,effective when a train occupies a given track circuit to prevent the manipulation of points which would endanger the train whilst on the track circuit.
Purpose : To prevent the manipulation of point under wheels
Application : In mechanical interlocking it is provided on point lever, lock lever and fouling bar levers .
In relay interlocking it is achieved at point initiation or point control or point operation stage.
5 S11 VER 1.0
• Track locking is provided for all power operated points
• In electro mechanical installation it is provided on point or lock lever
• It is effective at A & E positions of the lever
• Front contacts of point zone TPR are used in track locking circuit.
• A lever provided with track locking can not be operated unless the concerned track is clear .
• Fouling protection with track locking is to be provided when the distance between two adjacent track centres < 15’ 6” (17’ 38” for new works )
• In Relay interlocking circuits , WLR or WNR/WRR relays are used as electrical lock to ensure track locking of points . In these circuits the front contacts of point zone Track circuits are proved.
6 S11 VER 1.0
7 S11 VER 1.0
S11 VER 1.0 8
AE (AE) L
20 20
20T
20
20
TPR
A20T
20
20
B20T
A20
TPR
B20
TPR
AE (AE) L
20 20
S11 VER 1.0 9
S11 VER 1.0
Indication or check locking :Indication locking is defined as an arrangement to prevent the full stroke of a lever in an interlocking frame until such time the apparatus controlled by the lever have completed its movement. Indication locking is to be provided when there is no rigid connection between the lever and its function.
10
Indication locking
• It prevents out of correspondence between function and the control
• In Electro mechanical interlocking there is no rigid connection between the levers and functions .Hence indication locking is provided on the point and signal levers to prevent out of correspondence
• Indication locking on point lever is provided at B and D positions
• The point lever is electrically locked at B & D positions and is released only when the point is set and locked in the appropriate position
• This is achieved using the front contacts of point indication relays NWKR & RWKR
11 S11 VER 1.0
Indication locking
S11 VER 1.0 12
S11 VER 1.0 13
20
B
20
(BD) L
D
20
20T20
20
RWKR
20
NWKR
The indication locking is effective at B position for reverse to normal operation and at D
position for normal to reverse operation.
When point is operated from N to R the lever is locked at D position and the lock at D cannot
be energised unless RWKR is energised i.e., point is correctly set in reverse position. Similar
arrangement is provided for normal operation also
S11 VER 1.0 14
Combined Track and Indication Locking
(ABDE) L
20
A
20
20
E
20
B
D
20
20T20
20
TPR
20
NWKR
20
RWKR
Circuit 1 When combined Track and indication locking circuits are used separate
A and E spot contact should be used instead of one AE contact; otherwise, the
indication locking may not function
S11 VER 1.0 15
Circuit 2 This circuit dispenses with spot contacts, but Track failure
cause an indication Lock failure and the point indication failure may
cause a failure of track locking.
20
(ABDE) L
20
AB
DE
20
20
TPR
20
NWKR
20
RWKR
S11 VER 1.0 16
Circuit 3 If two electric lever locks are used as shown below. The
above said disadvantage can be eliminated. But this method is not
economical.
20
B
AE
20
20NWKR
(AE) L
20
RWKR20
D
20
20
(BD) L
20
TPR
S11 VER 1.0 17
Electrical Locking on Signal Levers -Indication Locking
FOR MOTOR OPERATED SEMAPHORE SIGNALS
B
SIGNAL LEVER
0°- 5° (B) L
(ON)
(B) L
SIGNAL LEVERRECR
B
Where motor operated signals or colour light signals are used, it becomes
necessary to ensure that before signal lever is replaced to Normal position, the signal
has assumed ON aspect, as there is no rigid connection between the signal lever and
the signal concerned.
It is achieved by providing Indication locking on signal lever, which is effective
at B position.
For Motor operated Semaphore Signals, ON aspect of signal is proved by 00
to 50 of arm contact or by signal normal relays which proves ON aspect of signals.
S11 VER 1.0 18
For colour light signals, it is not usual to prove the integrity of ON aspect of signal
lamps RECR contacts, as red lamp failure may cause hold up of concerned signal
lever and thereby delay to traffic.
To avoid the above undue delay, instead of using an energised contact of RECR, all
the de-energised contacts of signal controlling relays are proved in Indication locking
circuit of signal.
S11 VER 1.0 19
When signals are provided with Route indicators, to prove Route indicators are not lit
(de-energised condition) all the UR/UGR/UHRs are proved along with UECR back
contact.
(B) L
SIGNAL
B
HRUHRs
LEVER
WITH ROUTE INDICATOR
UECRHR
WITHOUT ROUTE INDICATOR
LEVER
B
SIGNAL
(B) L2 ASPECT
3 ASPECT(B) L
SIGNAL
B
LEVER UECRHR
B (B) L
DRDRHR
FOR COLOUR LIGHT SIGNALS :
ALL
UHRs
S11 VER 1.0 20
In some railways as an extra precaution, before allowing the signal lever to be
replaced full to its normal position, following conditions are introduced.
The OFF aspect ECRs of the 4 aspects signals (HECR, HHECR & DECR) may
also be proved in de-energised condition e.g. HECR,HHECR & DECR.
For the First stop Signal, not only the relays governing First stop Signal are
proved, but also aspects of its pre-warning signal (i.e. Distant) is also proved.
This is proved by Distant Signal controlling relays and the OFF aspects ECRs
(DHHR, DDR, DHHECR & DDECR) in de-energized condition.
S11 VER 1.0
Approach Locking Approach locking is provided on the signal lever to prevent the lever from Going to normal position in the face of an approaching train and to prevent the route being altered Purpose : To maintain route of signal in locked condition, once signal to that route is taken to OFF and loco pilot has accepted the signal Scope: Approach locking is effective when signal is taken to OFF and train within normal breaking distance from signal This is made effective at B position of signal lever .This is achieved by using the front contact of the approach track in the circuit.
21
S11 VER 1.0 22
S11 VER 1.0 23
• The back contact of TSR together with the front contacts of sequential route release proving relays are used to release the approach lock once the train passes the signal and clears the route in proper sequence.
• In busy yards , even before the first train clears the route the second train may come and occupy the approach track .In such cases to enable the operator to normalise the route the back contacts of TSR are provided along with the UYR contacts
• UYR relay contacts are used to prevent premature route release due to bobbing of replacement track circuit
• For emergency route release operation JR & JSLR relay contacts are used to release the route during emergency when the signal has been given but the train not passed and it is required to normalise the for some other movement .
24 S11 VER 1.0
APPROACH LOCKING
25 S11 VER 1.0
ALSR/ASR relay
• In relay interlocking , a relay named as approach lock stick relay (ASR/ALSR ) is provided to ensure approach locking
• Every signal has one ASR relay .Combined ASR may be provided for the signals which are conflicting to each other.
• ASR is normally in energised state. When the route is set and UCR is energized it causes ALSR to drop and there by locks the route .
• Back contact of ASR is used in HR circuit to ensure locking of that signal route before the signal is cleared .Front contacts of ASR are used to prove that conflicting signals are not operated
26 S11 VER 1.0
Length of Approach TC
Note: But for home signal generally no approach TC is provided and there fore dead approach locking is provided
SIGNAL Length of approach track circuit
Main line Starter 1 km in approach of signal i.e: up to home in rear
Loop line Starter Berthing track circuit
Shunt signal One track circuit before the signal
Home signal 1 km in approach of signal
27 S11 VER 1.0
1. THROUGH HOT CONTACT JSR PICKS UP AND MAINTAINS 2. THROUGH COLD CONTACT AND JSR FRONT CONTACT JR PICKS UP WHICH IS USED
IN RESPECTIVE CIRCUITS 3. USE OF HOT AND COLD CONTACTS ENSURES SAME TIME LAG FOR CANCELLATIONS 4. IF LEVER 1 IS REPLACED TO B POSITION WHEN THE TRAIN IS ON A1T THERMAL
ELEMENT HEATS UP THROUGH THE BACK CONTACT OF RELAY JSR
THERMAL RELAY CIRCUIT
28 S11 VER 1.0
S11 VER 1.0
ELECTRONIC TIMER
29
S11 VER 1.0
Where electronic timers are used, they are worked in parallel and their outputs are proved in series so that no premature release will take place in the event of failure of any one of the timers. Each timer’s output is connected to a neutral relay called NJPR Prove NJPR1 front in NJPR2 pick path and prove 2 front contact for route release.
30
S11 VER 1.0
DEAD APPROACH LOCKING
31
Where no track circuits or sufficient length of track circuit is not provided in rear of a
signal like Home signal, starter signals from goods yards, shunt signals from sidings, approach
locking is not possible.
In such cases another type of approach locking is adopted which becomes effective on
the reversal of the signal lever and does not depend on approach of train. Such locking is
known as Dead approach locking.
S11 VER 1.0 32
25
GOODS
LINES
(B)LB
25JR 25
UYR125 25
UYR2 TSR
BACK LOCK
TPRs
25
Once signal lever 25 is reversed it cannot be put back to Normal unless
the train passes the signal and causes the TSR to drop & Sequential
proving relays picks up or a time interval is elapsed.
Back Locking
• Either approach locking or dead approach locking can hold a route ,until the train passes the signal and clears the sequential proving tracks
• Once the train clears the sequential proving tracks , the approach and dead approach locking is released even though the train is still on the route .
• In order to hold the route until it is completely cleared by the train after passing the signal another type of Electrical locking is provided which is known as Route or Back locking
33 S11 VER 1.0
It is an Electrical locking which is effective when a train passes a signal and adopted to prevent manipulation of levers that would endanger a train while it is within the limits of the route entered .
• All the track circuits in the route of a signal except the berthing track are known as Back lock tracks
• Front contacts of all the back lock track tracks in the route of the signal are included in the route release circuit or ASR circuit
• Back locking takes care of the route holding when the train has passed the signal, but still it is within the limits of the route entered
34 S11 VER 1.0
Back Locking
S11 VER 1.0 35
10T
25
20
1913
14T
21
03BT03AT
02BT02AT
01BT01AT12
6 12
13T10
10
5
1T
22T 23
24 18
1
22Sdg.1
Sdg.2
12T
14
14
15
15
S11 VER 1.0 36
23
B (B)L
23
25
(B)LB
25
10
TPR
10
TPR
14
TPR
TPR12 10
TPR TPR13
18
B (B)L
18
NWKR10
Premature Route Release
• Initially , in the route release circuits , drop contact of TSR was used to prove the train arrival condition
• TSR is controlled by only one track circuit in advance of the signal.
• So, if the controlling TC fails momentarily , TSR will drop and route gets released, when the train is still on the approach TC ,without any time delay
• This is more dangerous and this type of route releasing is known as PREMATURE ROUTE RELEASE
37 S11 VER 1.0
S11 VER 1.0
NOT CORRECT
CORRECT
38
Sequential Proving Relays
• To prevent the premature route release , the front contacts of sequential proving relays is also included in the route release circuit along with the drop contact of TSR
• These relays are used to prove the condition of sequential occupation of and clearance of track circuits by the passing train .
• These relays energise in sequence as the train passes over the track circuits in succession after the signal.
• They are kept energised by stick path till the route is released
39 S11 VER 1.0
S11 VER 1.0 40
SIGNAL
RB UYR1
LEVERHR1stTPR TPR
2nd
UYR1
UYR2
2ndTPRTPR
1stHR LEVER
UYR2RB
SIGNAL
• In latest installations , where ever possible 3 track circuits in succession are used in different combinations ( 2 tracks occupied and one track clear) to energise UYR relays
• Proper functioning of these relays is checked by proving their back contacts in HR circuit
UYR1
41 S11 VER 1.0
42 S11 VER 1.0
S11 VER 1.0
Combined Indication Locking, Approach Locking, Back Locking and Route Release Circuit
43
SECTIONAL ROUTE RELEASE
• Back locking with a single ASR relay is suitable only for small way side stations. It is not suitable for larger yards with more parallel movements
• This is because all the points in the route remain in locked condition until ASR picks up with the clearance of last pair of points in the route.
• So in big yards a separate type of locking known as Sectional Route Release is adopted
44 S11 VER 1.0
SECTIONAL ROUTE RELEASE
• In SRR , locking of each section of the route is released as soon as the train clears that section with out holding the entire route until the last pair of points are cleared
• When SRR locking is adopted, the approach/dead approach on signal is released as soon as the train clears the first point zone track.
• The Back locking of remaining points in the route is taken care by special relays known as route lock stick relays(ULSR).
45 S11 VER 1.0
S11 VER 1.0
Sectional Route Release Circuit
46
S11 VER 1.0
Here approach lock on signal lever S1 is released as soon as
train clears 1T&2T.Now point no 2 is free for further movement.
But as the train is on 3T, now point no 3 is locked by track locking.
Point no 4 & 5 are locked by 4/5 ULSR Relay which is now in drop
condition.
47
•Route lock stick relay 4/5ULSR picks up only when 3T & 4T are UP .When 4T clears 4/5 ULSR picks up and Pt no 4 is released . •Locking on point no 5 is released when 5T is also cleared by the train . •When a movement takes place with the PT no 2 or 3 in reverse , it must not affect the locking of PT no 4&5 .To ensure this, normal band of S1 in 4/5ULSR circuit is bypassed with the reverse bands of Point levers 2 & 3 .
48 S11 VER 1.0
TLSR / TRSR Circuits
• In latest installations with bigger yards , the point zones are divided into various sub routes
• Each sub route is associated with directional relays known as TRSR & TLSR
• TRSR relays are used for releasing the routes in Rightward movement .
• TLSR relays are used for releasing the routes in Leftward movement .
• Back contacts of TRSR/TLSR are proved in signal clearance circuit ( HR )
• Front contacts of TRSR/TLSR of opposite direction are also proved in signal clearance circuit ( HR ) to ensure locking of conflicting signals
• Where TLSR/TRSR relays are used for SRR , the ASR relay circuit should include at least one point zone track circuit after the respective signal.
49 S11 VER 1.0
TABLE OF CONTROL
1 S11 VER 1.0
• It is also known as Selection Table or Route Control Chart
• The table of control is provided basing on the essentials of interlocking and the signal interlocking plan of the station
• It contains the following information for each signal route of a yard.
a) Conditions to be fulfilled before taking off the signal
b) Conditions to be maintained after taking off the signal for the set route
c) Conditions to be fulfilled for releasing the locked route
d) Conflicting signals to be locked
2 S11 VER 1.0
e) Other special conditions
i )Siding point control
ii) LC Gate closed condition
iii) Signal ahead should not be blank
iv) Approach TC occupation for Call ON signal
v) Crank handles to be locked
vi) Block instrument control for LSS
vii) Aspects of signals ahead
3 S11 VER 1.0
COLUMN NUMBER CONTENTS OF THE COLUMN
1 SERIAL NUMBER
2 SIGNAL NUMBER
3 ROUTE
4 ASPECT OF THE SIGNAL
5 APPROACH /DEAD APPROACH LOCKED BY
6 BACK LOCKED BY
7 CONTROLLED BY TRACKS
8 CONTROLLED BY ASPECT OF SIGNAL AHEAD
9 CONTROLLED BY CRANK HANDLE ZONE
10 & 11 LOCKS AND DETECTS POINTS NORMAL/REVERSE
12 LOCKS SIGNAL NORMAL
13 OTHER CONTROLS
14 REMARKS
4 S11 VER 1.0
S11 VER 1.0
COL1: Serial number – The column details the serial no of signal routes in
the control table
COL2:Signal number – This is written as the signal no
COL3:Route – The route to which signal is cleared .The route can
be identified as a) either Road1, Road2 etc b) up to next signal in advance or c)to
clear of the first opposing signal (eg :shunts) or may be identified by an alphabet
1A,1B etc
COL 4 : Aspect of signal – OFFaspect of the signal. Each OFF aspect may be
dealt separately viz., HG,HG+UG,HHG,DG etc.
COL5:Approach locked by – The conditions to be satisfied for cancelling the
Movement(for both Approach and Dead Approach locking).For providing approach
Locking, the length of the approach track circuit shall be adequate
a)Home signal (FSS) – Normal breaking distance+Reaction distance
b)Starters – Berthing Tracks
c)Shunts – The tracks from which train is expected to start
Otherwise , it shall be mentioned with 60/120 secs.
Time delay for run through movement, the approach locking for main line starter
will be effective from the first stop signal in the rear.
5
S11 VER 1.0
COL6: BACK LOCKED BY
All signals except calling-on signal will have to be given this
Condition, by proving track circuits up to last point track in the route excluding
The berthing tracks
COL7: CONTROLLED BY TRACKS
Track circuits free in the route and overlap
COL8: CONTROLLED BY ASPECT OF SIGNAL AHEAD.
This column provides the necessary red lamp protection
COL9: CONTROLLED BY CRANK HANDLE ZONE.
This column provides various groups of crank handle to be proved.
The minimum number of crank handles to be provided on single is 2
And the same on double line is3.
COL10&11: Locks and detects points
COL12: Locks signals
COL13: Other Controls
Slot, Block control,LCgate,Locally operated points, plungers in the case of
Trains dealt from track circuit to non track circuited lines or goods lines
COL14: This column meant for any other conditions to be fulfilled before clearing
A signal and not covered by any of the columns above.
6
Preparation ,Testing & Approval of TOC
• TOC is to be approved by CSTE or CSE
• It should also to be included in the documents to be submitted along with application for CRS Sanction
• Every new installation before commissioning has to be tested with TOC
• Also when ever any alteration is done in the existing yard , the installation has to be tested with modified TOC
7 S11 VER 1.0
S11 VER 1.0 8
• Calling on and Shunt signals doesn't prove Berthing track circuits
S11 VER 1.0
ROUTE= ROUTE+BERTHING TRACK + OVERLAP CONTROLLED BY TRACK CIRCUITS= ROUTE + BERTHING TRACK ROUTE/BACK LOCK= ALL THE TRACK CIRCUITS FROM FOOT OF SIGNAL TO LAST POINT ZONE.
9
S11 VER 1.0 10
S11 VER 1.0
While preparing control table remember the following guide lines 1)Between two shunt signal movements physical isolation is not required 2)Between two running signal movements physical isolation is must 3)Between shunt and calling on signal movements physical isolation is must 4)Between running and shunt signals movement physical isolation is must Permitted through movement in same direction 1)Main and Main 2)Shunt and Shunt Non permitted movements in same direction 1)Main and Shunt, vice versa 2)Main and calling on , vice versa 3)Shunt and calling on ,vice versa.
11
Only directly conflicting signals are shown .But in HR/UCR CIRCUITS We will prove direct and indirectly conflicting signals. Calling on and Shunt signals does not prove berthing track circuits.
12 S11 VER 1.0
S11 VER 1.0 13
S11 VER 1.0 14
S11 VER 1.0
Advance starter does not have approach and back lock tracks. Calling on has dead approach and no back lock Distant signal has no approach, back lock points, signal&route buttons Advance starter should lock emergency cross over).Advance Starter has no ASR.
15
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
1 1D(2) 1D(1) - - - - - - - - - - - - - - -
1D(1) HG/
HHG/ DG
1D(1) DG/ HHG
DG CONTROLLED BY 1D(1) DG/HHG WITH
POINT NO 13N
2 1D(1) S1 - - - - - - - - - - - - - - 1 RG
/HG/DG
1 HG/ DG
1DG
3 1 UP MAIN 11, 13
- - - 18, 20 - 1T,11AT,
13BT,UMT
18BT, 20AT, 3/4T
- CH1,CH2 DEAD
APPROACH 1T, 11AT,
13BT 1A,21 -
3 RG/HG/DG
- 3DG TIME RTELESE 120 SEC
16
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
4 1 COMMON LOOP
SET TO BS 11 13 - - 18 -
1T,11AT, 13BT,13AT
,CLT 18AT - CH1,CH2
DEAD APPROACH
1T, 11AT, 13BT, 13AT
1A,21 4 RG TIME RTELESE 120 SEC
1UG REQUIRED
5 1
COMMON LOOP SET TO MAIN
11 13 - - 20 18 1T,11AT,
13BT,13AT,CLT
18AT, 18BT, 20AT, 3/4T
- CH1,CH2 DEAD
APPROACH 1T, 11AT,
13BT, 13AT 1A,21
4 RG/ HG
- - TIME RTELESE 120 SEC
1UG REQUIRED
6 1A UP MAIN 11, 13
- - - - - 1AT
OCCUPIED
- - CH1,CH2 DEAD
APPROACH -
1,3,4,21
(30,30AW20
R)
- - - - TIME RELEASE 240 SEC APPROACH CLEARED
AFTER 120 SEC COGGN
17
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
7 1A COMMON LOOP
11 13 - - - - 1AT
OCCUPIED
- - CH1,CH2 DEAD
APPROACH -
1,4,21, (30AW
20R) - - - -
TIME RELEASE 240 SEC APPROACH CLEARED
AFTER 120 SEC COGGN
8 3 UP MAIN 18, 20
- - - - - 18BT,20AT
,3/4T - - CH1,CH2
UMT (1W13N)
18BT, 20AT
(1AW13N),
(10W11R13N
) ,21,23
- 6RG/ DG
- 6DG TIME RLEASE 120 SEC DG CONTROLLED BY
6DG
9 4 UP MAIN 20 18 - - - - 18AT,18BT
,20AT, 3/4T
- - CH1,CH2 CLT 18AT,
18BT, 20AT
1A, (10W1
1R), 21,26
- 6RG/ DG
- - TIME RELESE 120 SEC
18
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
10 6 7D(2) 20 - - - - - 6T,
UP ACPR - -
CH2,22LX
- - 21 - - - 7D(2) HHG/
HG -
11 7D(2) 7D(1) - - - - - - - - - - - - - - - 7D(1)
HG
7D(1) HG/ DG
DG CONTROLLED BY 7D(1) DG
12 7D(1) 7 UP IBS - - - - - - - - - - - - - - 7 RG/
DG - 7DG
DG CONTROLLED BY 7 DG
19
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
13 7 UP MAIN - - - - - - 7T - - - - - - - - - - CONTROLLED BY UP
SIDE BLOCK INSTRUMENT
14 10 DN LOOP 11 12 - - - - 11BT,12B
T,12AT - - CH1,CH3 26-28T
11BT, 12BT, 12AT
25,27,30,
(30AW20N)
- - - - TIME RELEASE 120 SEC
15 10 DN MAIN 11, 1 2
- - - - - 11BT,12B
T - - CH1,CH3 26-28T 11BT, 12BT
25,28,30,30
A - - - - TIME RELEASE 120 SEC
20
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
16 10 UP MAIN 13 11 - - - - 11BT,11AT
,13BT - - CH1,CH2 26-28T
11BT, 11AT, 13BT
3,4,23,25,
(21W18N),
(30AW19R12
R), (30,30AW19
N)
- - - - TIME RELEASE 120 SEC
17 10 COMMON LOOP
- 11, 13
- - - - 11BT,11AT,13BT,13A
T - - CH1,CH2 26-28T
11BT, 11AT,
13BT, 13AT
4,25,26,
(21W18R),
(30AW19R12
R), (30,30AW19
N)
- - - - TIME RELEASE 120 SEC
21
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
18 21 UP MAIN 20, 18
- - - - - 20AT,18BT - - CH1,CH2 3/4T 20AT, 18BT
1,1A,3,6,26, (10W11R13N
)
- - - - TIME RELEASE 120 SEC
19 21 COMMON LOOP
20 18 - - - - 20AT,18BT
,18AT - - CH1,CH2 3/4T
20AT, 18BT, 18AT
1,1A,4,6,26, (10W11R13R
)
- - - - TIME RELEASE 120 SEC
20 23 DN MAIN 13 11 - - - - 13BT,11AT
,11BT - - CH1,CH2 UMT
13BT, 11AT, 11BT
3,10,25,
(30AW20N19
N) (30AW19R12
R)
- - - - TIME RELEASE 120 SEC
22
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
21 25 DN MAIN - - - - - - 25T - - - - - 10,23 - - - - CONTROLLED BY DN
SIDE BLOCK INSTRUMENT
22 26 DN MAIN - 10, 13
12 - - - 13AT,13BT,11AT,11BT, 26-28T
- - CH1,CH2
,CH3 CLT
13AT, 13BT, 11AT, 11BT,
4,10,21,
(30AW19N)
- 25 RG/
DG - - TIME RELEASE 120 SEC
23 27 DN MAIN 11 12 - - - - 12AT,12BT
,11BT, 26-28T
- - CH2,CH3 DLT 12AT,
12BT, 11BT
10,
(30AW20N)
- 25 RG/
DG - TIME RELEASE 120 SEC
23
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
24 28 DN MAIN 11, 12
- - - - - 12BT,11BT,26-28T
- - CH2,CH3 DMT
(30W19N20N)
12BT, 11BT
10, (30AW19N20
N)
- 25 RG/
DG -
25 DG
DG CONTROLLED BY 25 DG
TIME RELEASE 120 SEC
25 30 DN LOOP SET TO BS
20 19 - - 12 - 30T,20BT, 19T,DLT
12AT - CH2,CH3
, 22LX DEAD
APPROACH 30T, 20BT,
19T
(10W11N), 30A
27 RG
- - - 30 UG REQUIRED
TIME RELEASE 120 SEC
26 30
DN LOOP SET TO MAIN LINE
20 19 - - 11 12 30T,20BT, 19T,DLT
12AT, 12BT, 11BT,
26-28T
- CH2,CH3
, 22LX DEAD
APPROACH 30T, 20BT,
19T 10,30
A
27 RG/ HG
- - - 30UG REQUIRED
TIME RELEASE 120 SEC
24
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
27 30 DN MAIN 19, 20
- - - 11, 12 - 30T,20BT, 19T,DMT
12BT, 11BT,
26-28T -
CH2,CH3, 22LX
DEAD APPROACH
30T, 20BT, 19T
10,30A
-
28 RG/ HG/ DG
- 28 DG
TIME RELEASE 120 SEC
28 30
COMMON LOOP SET TO
BS
- 20, 18
19 - 13 -
30T,20BT, 20AT,18BT,18AT,CL
T
13AT -
CH1,CH2,
CH3,22LX
DEAD APPROACH
30T, 20BT, 20AT, 18BT, 18AT,
1A,30A,
(10W11Ror1
2N)
26 RG
- - - 30UG REQUIRED
TIME RELEASE 120 SEC
29 30
COMMON LOOP SET TO MAIN
- 20, 18
19 - - 13, 11
30T,20BT, 20AT,18BT,18AT,CL
T
13AT, 13BT, 11AT, 11BT,
26-28T
-
CH1,CH2,
CH3,22LX
DEAD APPROACH
30T, 20BT, 20AT, 18BT, 18AT
10,30A
26 RG/ HG
- - - 30UG REQUIRED
TIME RELEASE 120 SEC
25
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUTE IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
30 30A DN LOOP 20 19 - - - - 30AT
OCCUPIED
- - CH2,CH3
, 22LX DEAD
APPROACH -
(10W11Nor1
2R), (23W12R),27
,30
- - - - TIME RELESE 240 SEC APP CLEARED AFTER
120 SEC COGGN
31 30A DN MAIN 20, 19
- - - - - 30AT
OCCUPIED
- - CH2,CH3
, 22LX DEAD
APPROACH -
10,23,26, 27,
28,30
- - - - TIME RELESE 240 SEC APP CLEARED AFTER
120 SEC COGGN
32 30A COMMON LOOP
- 20, 18
19 - - - 30AT
OCCUPIED
- - CH1,CH2
, CH3, 22LX
DEAD APPROACH
-
1A,26,30,
(10W11Ror1
2N)
- - - - TIME RELESE 240 SEC APP CLEARED AFTER
120 SEC COGGN
26
S11 VER 1.0
SL.
NO
.
SIG
NA
L N
O.
DES
TIN
A-T
ION
LOCKS / DETECTS POINT CONTROLLED BY TRACK
CIRCUITS OTHER
CONTROLS
IF ANY
AP
PR
OA
CH
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
BA
CK
LO
CK
ED B
Y
TRA
CK
C
IRC
UIT
S
LOC
KS
SIG
NA
LS SIGNAL ASPECT
REMARKS ROUTE
ISOLATION
OVERLAP
RO
UTE
OV
ERLA
P
FOU
LIN
G Y
WITH ROUT
E IF
Y IF
YY IF
G IF
NO
R
REV
NO
R
REV
NO
R.
REV
.
CH, LXC, SDG
SLOT, etc.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
33 30D(2
) 30D(1) - - - - - - - - - - - - - - -
30D(1) /HG /HHG /DG
30D(1) / DG / HHG
DG CONTROLLED BY 30D(1) DG/HHG WITH
POINT 19N 20N
34 30D(1
) S30 - - - - - - - - - - - - - -
30 RG /HG /DG
30 HG /DG
30 DG
27
Crank Handle Interlocking
• Where points are operated by point machines ,crank handles are provided to facilitate manual operation of points in case of failures .
• Once a signal is taken off , manual operation of any point in the signalled route ,may endanger the train.
• Hence it is essential to interlock crank handles with the signals.
• To achieve optimum facility of traffic movements crank handles are grouped .
10/26/2020 1 S11 VER 1.0
11 20
18
12
13
19
Emergency crossovers are kept in the same group as they are rarely operated .
10/26/2020 2 S11 VER 1.0
Crank Handle is common for all points of a yard . Each point machine is provided with a key locked door which normally locks the crank handle entry point in closed state normally To open this one key known as Crank handle key has to be inserted into the point machine at the crank handle entry point.
10/26/2020 3 S11 VER 1.0
The crank handle key is normally kept locked in a EKT or special relay KLCR . This key can not be taken out if the route is set for a signalled move over those points.
10/26/2020 4 S11 VER 1.0
When CH key is taken out , it will not be possible to 1) Operate the points from panel/cabin 2) Clear any concerned signals
10/26/2020 5 S11 VER 1.0
10/26/2020 6 S11 VER 1.0
Each group of crank handle is provided with a key of different ward ,so that key of one CH group can not be used for the points of other CH groups of the yard.
10/26/2020 7 S11 VER 1.0
Grouping of crank handles. 1. Crank handle zones are decided in such a way that whenever crank handle is
taken out 2. There will be only minimum disturbance in the yard 3. Used to maintain the flexibility of the yard. 4. Used to achieve minimum interruption to the traffic 5. At way side stations up line , down line , and emergency cross over 6. Emergency crossovers are kept in the same group, as they are operated very
rarely 7. Crank handle taken from one group will not go to another group, this achieved
with the help of wards 8. Crank handle is locked in EKT 9. EKT wards of crank handle is also very important. The same ward EKT should
not used for different group of crank handles 10.Key, crank handle and point machine keys are welded together for safety
purpose 11.Point machine has two keys a) One key to open the flap b) Other key to run
the crank handle. 10/26/2020 8 S11 VER 1.0
10/26/2020 S11 VER 1.0 9
SIDING CONTROL CIRCUIT
• Where there are no frequent movements to and from siding lines , the points in the siding are operated locally by ground lever frames .
• But these ground lever frames are controlled from the cabin/panel
• The siding points are normally kept in locked position .They can be released only when there is no signalled movement in that zone
• For the sake of interlocking siding normal proving relay NPR is provided at cabin. The front contacts of this relay used in signal clearance circuit
• Generally a pair of EKT are connected between cabin and siding point to transmit and release permission to operate siding point .
10/26/2020 10 S11 VER 1.0
10/26/2020 S11 VER 1.0 11
10/26/2020 S11 VER 1.0 12
10/26/2020 S11 VER 1.0 13
CALLING ON SIGNAL
It is a subsidiary signal which can be fixed below any stop signal except LSS (a) To receive a train on an occupied line or (b)When the main signal above it, can’t be taken off due to (i) Failure of track circuit/circuits in advance (ii)Failure of points (indication) in overlap. (iii)Signal in advance is blank. (iv) Failure of route indicator etc. Calling-on signal can be taken off only when the train has come to a stop at the foot of the signal.
10/26/2020 14 S11 VER 1.0
CALLING ON SIGNAL
Conditions to be fulfilled:- •All points in the route including isolation are correctly set for calling-on signal •Calling-on track circuit occupied •Crank Handles of the power operated points if any, are ‘IN’ and locked. •Signal in advance is not taken off •Conflicting signals are at ON •LC Gate in the route closed and locked against the road traffic.
10/26/2020 15 S11 VER 1.0
CALLING ON SIGNAL
•Train has come to a halt at the foot of the signal. This is ensured by a time delay circuit which is initiated after ensuring that the train has come on the calling-on track circuit. •Respective slot is received from the other agency (applicable to end panels/cabins). separate slots the main signal as well as the calling-on signal.
•Cross protection is provided to calling-on HR
10/26/2020 16 S11 VER 1.0
CALLING ON SIGNAL
Relevant control switch/button (COGGN) operated together with the main signal lever already in pulled condition. In automatic section first track circuit in advance is clear and TSR in case of calling-on signals provided. HR of signal above is proved in de-energized position
10/26/2020 17 S11 VER 1.0
INDICATION CIRCUITS
TPR
TPR
TRACK INDICATION
Purpose :- to indicate whether the track is clear or occupied.
This may be –
1) Spot indication type
used for signal /
point indication
2) Slot/Strip Light type
Track circuit occupied Track circuit clear and route locked
POINT INDICATION
Purpose :- to indicate the position of the point
B12
N
RWKR
NWKR
NWKR
RWKR
R N12
N12
B12
RWKR
NWKR
12V, 4W, SL5
Signal Indication
Purpose :- to indicate the aspect of the signal in the cabin/panel
B12 DKE DECR
HECR
RECR
UECR
N12
HKE
RKE
UKE(W)
12V, 4W, SL5