1

LOCO TCAS
OPERATING MANUAL
Operating & trouble shooting instructions
for loco pilots working with TCAS fitted
duel-cab electrical locos &
diesel electric locomotive

South central railway.

P.V.GIRI/LP/SC
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MESSAGE

Locomotives have been in service in south central

railway since 1963. With the experience gained in their operation. It is
seen that a large number of link casualties as well as TCAS failures can
be avoided by prompt action and alertness on the part of loco pilot.
For the benefit of the pilot’s these instructions. The subsequent
pages highlight in brief the symptoms of various defects and relevant
remedial action recommended for the running crew to avoid TCAS
failures. It is imperative that the pilot’s know the full sequence of
operation and remedial action recommended for rectifying these defects.
I am sure that the book is quite helpful and brings glimpse of
knowledge for running staff.

GOPAL M
Sr DEE/TRSO

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Contents Page no
1. Introduction -------------------------------------- 6
2. DRIVER MACHINE INTERFACE ------------------ 7

2.1 Display unit (DMI) front panel.----------------- 7

7
2.2 Default screen. -------------------------------------------
------------ 8
2.3 Train type / configuration selection. ----------------------
-------
3. OPERATIONAL MODES ----------------------------------------- 8

3.1 Standby mode. ------------------------------------------------------ 8

3.2 Staff responsible mode. ------------------------------------------ 8
3.3Llimited supervision mode. --------------------------------------------- 8
3.4 Full supervision mode. ------------------------------------------- 8
3.5 Override mode. ------------------------------------------------------ 9
3.6 On sight mode. ------------------------------------------------------ 9
3.7 Trip mode. ------------------------------------------------------------ 9
-3.8 Post trip mode. -----------------------------------------------------
9
3.9 Reverse mode. ------------------------------------------------------ 9
3.10 Shunt mode. ------------------------------------------------------- 9
3.11 Non-leading/banker mode. ------------------------------------ 10
3.12 System failure mode. -------------------------------------------- 10
3.13 Isolation mode. ---------------------------------------------------- 10
-
11
4.TCAS OPERATIONAL PROCEDURES
4.1 TCAS powering procedure. 11
4.2 Starting up procedure of TCAS. 12
4.3 Staff responsible procedure. 12
4.4. New train formation “or” cab/desk change (other 12
than shutting) procedure.
4.4.1 BL- key removed in normal mode for any reason. 14
4.5 Shunting operation procedure. 14
4.5.1 To perform shutting. 15
4.6 Isolation procedure. 15
4.7 Non-leading (multiple loco) banker operation 15
procedure.
4.8 Reversing procedure. 16
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4.9 Train trip recovery procedure and SPAD.------------------- 16

4.10 Over riding procedure(signal or station TCAS failure. 16

4.10.1 Procedure for passing signals at “ON” 17

1. HOME OR STARTER SIGNALS.------------------------ 17

----
2. ADVANCE STARTER. --------------------------------- 17

3. --------
IBS SIGNAL. ----------------------------------------------------- 17

18
4. Gate Stop signal. ------------------------------
5. --------
PROCEDURE FOR PASSING “WHEN CALLING ON 18
SIGNAL IS TAKEN OFF: -------------------------------------
------------ 18
6. PROCEDURE for recovery from TRIP MODE. ---------
-
7. EVENTS when a signal is put back to “ON” on 19

approach.
8. STEPS TO BE TAKEN IN CASE OF TCAS SYSTEM FAILURES, 19
------------------------------------------------------------
19
9. BREAK APPLICATION DUE TO ROLL AWAY PROTECTION,
---------------------------------------------------------

5. SOS GENERATION AND RECEPTION 20

5.1 Self-loco generated SOS. -------------------------- 20

5.1.1 Manual SOS. ----------------------------------------- 20

-5.1.2 Block stop S0S. ------------------------------------- 20

5.2 Other loco generated SOS. ----------------------- 20

5.3 Station generated SOS. ----------------------------- 20

6. Crew Messages. ----------------------------- 21

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1. INTRODUCTION
1.2 Introduction Train Collision Avoidance System (TCAS) is a crew friendly train
protection system which provides the following features and train protections:
1. Signal Passing at Danger (SPAD) prevention
2. Onboard or cab signaling
3. Turn out or point speed monitoring
4. Section speed and Permanent Speed Restrictions (PSR) monitoring
5. Temporary Speed Restrictions (TSR) monitoring. (If received from track side)
6. Head on/ rear end and side collision prevention
7. Standstill and rollaway protections
8. Manual and automatic SOS generation
9. LC gates alert in advance to loco pilot with automatic whistling feature.
10. Automatic train length computation and loop line clear indications to loco pilot

1.3 Loco TCAS Sub systems consists of the following sub systems:
1. TCAS Control Unit (In compartment).
2. Two Driver Machine Interface (DMI)s (at each cab/ desk)
3. Two RFID Readers (at bottom end of each locomotive)
4. Two Radios ( In compartment)
5. TCAS interacts with locomotive brakes depending on the locomotive brake
system for applying brakes

1.4 TCAS Operation Loco TCAS reads the track information (kilometer, position, section
speed, track ID, etc) from track-side preprogrammed RFID tags through RFID readers.
 Based on current loco position, Track ID and direction of train movement, Station
TCAS gives movement authority, signal information and turnout speed with distance
 Based on signal information from station TCAS and available track data, Loco TCAS
decides the most restrictive target and monitors it.
 Based on the train current speed and braking characteristics, TCAS advices safe
permitted speed to loco pilot. If loco pilot exceeds this limit, TCAS will apply
appropriate brakes to control train within safe speed limits.
 Whenever the target distance is far away, Loco TCAS monitors the most restrictive
speed (minimum of section speed, loco max speed, train Max speed, mode related
speed, loop line speed, PSR, and TSR). This speed limit is displayed to loco pilot as
Max Permitted speed. If Train speed is above permitted speed limit by 2 kmph, Over
speed alarm shall be issued 5 kmph, Normal service brake shall be applied. 10
kmph, Full service brake will be applied. 15 kmph, Emergency brake shall be
applied. Whenever the target approaches, in addition to most restrictive speed,

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2. DRIVER MACHINE INTERFAC

2.1 Display Unit (DMI) Front Panel

Front panel of the Display Unit mounted on the control desk is shown below.
Number of dedicated (hard) and context sensitive (soft) keys are provided on the
unit.

Display ON/ OFF

Cancel key
29/04/09 07:44:18
DPC MENU

1. LINKING Display Are

2. FAULT MESSAGES
3. CREW MESSAGES a
Contrast/Brightness

Control keys

Faults key Menu ke 1 2 3 Enter key

Soft keys

2.2 Default Screen

Loco ID

Target
Type
Permit
Speed
Current
Speed
Movement
Target
Authority
Distance
Mode
Symbol
Mode
DC Name

Tag
Indicatio
n

Targe Train Sectio Loco Context Communicatio

t Lengt n Locatio Functio
Keys Message n
Spee h Speed n s with Station
Typical DMI Screen will be shown below with Brief fields Explanation.

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2.3 Train type/configuration selection screen

Train type/ configuration selection is required when a new train is formed. TCAS prompts
Loco Pilot to select this configuration when TCAS detects a new train formation.

TRIAN TYPE SELECTION

• Light engine
• Goods/freight train
• Passenger train
• Back
1 2 3 4 5 6 7 8 9 0

3. OPERATIONAL MODES
3.1 Standby Mode Standby mode is default mode. At power on, or if no CAB/
Desk is selected, TCAS comes into this mode.

1. Standstill protection (If any movement is detected, it applies the brake).

3.2 Staff Responsible Mode Staff Responsible mode can be selected by Loco
Pilot on Power on/ new Train formation. TCAS automatically falls back to this
mode when both the signal and Track data are not available.

1. Locomotive/ Train ceiling speed limit 2. Rollback protection

3.3 Limited Supervision Mode Entry to Limited supervision mode is automatic.

When either of the Track data or Signal data is available,
Locomotive/ Train ceiling speed limit
1. Rollback protection
2. SPAD prevention/ Turn out speed limiting only if signal data is available
3. Section speed limits/ PSR monitoring only if track data is available
4. Reverse movement protection
5. LC gate warning
6. SOS generation/ reception (If radio communication is available)
7. Collision prevention in block section (If Radio communication is available)

3.4 Full Supervision Mode Entry to Full Supervision Mode is automatic. When both
the Track data and Signal data is available, TCAS enters into this mode.

1. Locomotive/ Train ceiling speed limit

2. Rollback protection
3. SPAD prevention/ Turn out speed limiting
4. Section speed limits/PSR monitoring
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5. Reverse movement protection

6. LC gate warning
7. SOS generation/ Reception (If Radio communication is available)
8. Collision prevention in block section (If Radio communication is available

3.5 Override Mode Entry to Override Mode is manual. TCAS enters into Override
mode, when MA is less than 200 m, Train is at standstill and Loco Pilot selects override button
'OVRD' on DMI .Override mode Speed Limit (30kmph).

Loco Pilot has to cross the signal in 255 seconds after selecting override
mode. If MA is increased before crossing the signal, TCAS comes back to LS/
FS mode.

3.6 Onsight Mode Entry to this Onsight Mode is automatic. TCAS enters into Onsight
Mode when Train crosses signal foot in Override mode.
Onsight mode speed limit (30kmph).
TCAS exits from Onsight mode to SR/ LS mode, when Loco Pilot selects SR
mode or Override signal or LSS or Gate signal. For all other type of signals,
TCAS exit this mode after crossing the next signal at OFF aspect (other than
Danger).

3.7Trip Mode Entry to Trip Mode is automatic. TCAS enters into Trip Mode when Train
exceeds MA.

Applies unconditional Emergency Brake.

Loco Pilot has to acknowledge Train Trip by selecting 'P_TRP' button on DMI.

3.8 Post Trip Mode Entry to Post Trip Mode is manual. TCAS enters into this mode
when Loco Pilot acknowledges train trip and when train is at standstill.
Post Trip mode Speed Limit (30kmph).
TCAS exits from Post Trip mode to SR/ LS mode when,
1. Loco Pilot selects SR mode and when Train is at standstill.
2. Train crosses next signal at OFF aspect (other than Danger).

3.9 Reverse Mode Entry to Reverse Mode is manual. TCAS enters into Reverse Mode
when Loco Pilot selects 'REV' button on DMI and when Train is at standstill and reverser is
centered.

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3.10 Shunt Mode

Entry to Shunt Mode is Manual. TCAS enters into shunt mode when Loco
Pilot selects 'SHNT' button on DMI and when Train is at standstill.

Shunt mode speed limit (15Kmph).TCAS exits from SHNT mode to SB mode,
when Loco Pilot selects 'SHNT' button on DMI and when Train is at
standstill.

3.11 Non - Leading/ Banker Mode Entry to Non- Leading Mode is Manual.
TCAS enters into this mode, when Loco Pilot places NL/ Leading switch in NL position
in both CABs/ Desks, when Train is at standstill
No supervisions and brakes will be bypassed.
TCAS exit from Non- Leading Mode, when Loco Pilot Places NL/ Leading
switch in Leading position in both CABs/ Desks, when Train is at standstill.

3.12 System Failure Mode

Entry to System Failure Mode is Automatic. TCAS enters into this mode,
when TCAS encounters a system critical fault.
Applies unconditional brake. TCAS exits from system failure mode, when critical fault
recovers.

3.13 Isolation Mode Entry to this Isolation Mode is Manual. TCAS enters into this
mode, when Loco Pilot places isolation/ normal switch in isolation position.
No Supervisions and Brakes will be bypassed. TCAS exits from Isolation Mode when
Loco Pilot places Isolation/ Normal switch is in normal position

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4. TCAS OPERATIONAL PROCEDURES

4.1 TCAS Powering Procedure
1. Energize loco as per extant procedure.
2. Since TCS is off condition, EB shall remain applied.
3. To start TCAS ensure that all TCAS MCBs are in on condition (Switch on MCB-1 and
MCB-2)
4. Loco TCAS have two circuit breakers. MCB-1 for Driver Machine Interface (DMI) s
and MCB-2 for TCAS control unit.
5. Wait till DMI booting completes. After completion, TCAS Main screen will be
displayed. This will take around 3 minutes.
6. Ensure that Emergency Brake (EB) bypass cock (highlighted in red in figure
-1) is open. (The cock knob should be in vertical position as shown in figure -2 )
Fig .1 fig.2

Fig 4.1

7. Ensure that TCAS isolation switch is in normal position as shown below in Fig

8. For non-leading locomotive operation, keep leading/ non-leading switch (provided

on DMI) in non-leading position in both cabs/ Desks. Go to non-leading operation
procedure.

9. For leading locomotive operation, keep leading/ non-leading switch (provided on

DMI) in leading position in both cabs/ desks.

10. 12TCAS will be in standby (SB) mode. Now follow new train formation procedure.

NOTE: In the event of system failure on booting for the first INSTANCE, try to re-boot TCAS
system for 2 more times by switch off and on battery switch on OBC rack with a time
INTERVAL of ATLEAST 30sec. if not successful by pass TCAS as per isolation procedure.

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4.2 STARTING UP PROCEDURE OF TCAS

 In standby mode and TCAS indicating healthy, press “SR” key following by “CNFM”
button.

 The equipment will switch SR mode and permit train movement.

 Now the train is ready to start.

 After starting and passing the two RFIDs, TCAS will automatically change to normal
mode.

 If not change to normal mode after passing RFIDs, it will continue in SR mode. It will
change to normal mode after passing subsequent RFIDs

4.3 Staff Responsible Procedure

Loco Pilot can select SR mode to move under his/ her own responsibility, till a valid
Track Data and MA is acquired by Loco

4.4 New Train Formation or change CAB/ Desk change

(other than Shunting) procedure
1. Ensure Driving Cab/ Desk is activated (Insert BL key (Electric Locos) or place
Reverser handle in forward position (in Diesel Locos)).
2. Ensure MR is above 6.75 kg/cm2, BP is above 4.8 kg/cm2. TCAS waits until
MR and BP comes to these limits.
3. TCAS performs automatic brake test by applying NSB, FSB and EB.
NOTE; - If TCAS is in Powering procedure and if steps 1 & 2 are Satisfied, Brake
test will be done while DMI is Booting. This is to minimize power up sequence
time
4. After completion of Brakes test, Brakes Test result shall be displayed on DMI.
If Brake Test fails, Loco pilot can retest the brakes by pressing ACK button
on DMI.Until brakes test success, Loco TCAS retains in Standby mode. If
Brake Test fails continually, Loco Pilot can isolate TCAS unit. (Refer
TCAS Isolating Procedure

5. On Successful completion of Brake Test, Loco Pilot shall be advised to select

Train Configuration.

Train Configuration will be selected by following Procedure:

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a. By pressing CONFIG button on DMI, Train class screen shall be displayed.

TRIAN TYPE SELECTION

• Light engine
• Goods/freight train
• Passenger train
• Back
1 2 3 4 5 6 7 8 9 0
Fig

b. Select required train class (light engine, passenger, freight trains)

TRIAN TYPE SELECTION

1. Light engine
2. Goods/freight train
3. Passenger train
4. Back
Press “E” key to continue…
1 2 3 4 5 6 7 8 9 0
Fig
c. Select required train class (light engine, passenger, freight trains)

Passenger train types

1. Passenger train 27 coach
2. Passenger train 5 coach
3. Passenger train 10 coach
4. Passengertrain15coach
5. Passenger trai20coach
6. Manual entry
Press “E” key to
continue..
1 2 3 4 5 6 7 8 9 0

d. On selection of Train Class, the available Train configurations for this class will be displayed.
Select the appropriate train configuration and reconfirm the train configuration

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e. On successful selection, Selected Train configuration data will be loaded by TCAS

and Train configuration will be displayed on the DMI main screen.

6. Now, TCAS is ready to operate. It suggests Loco Pilot to select Staff

Respond- sible (SR) or Shunt Mode (SH) to select.
7. If Shunt mode (SH) is selected, refer shunting operation procedure.
8. If Staff responsible (SR) is selected, refer TCAS Staff Responsible procedure.

4.4.1 BL KEY REMOVED IN NORMAL MODE FOR ANY REASON

 On removing BL key, the TCAS shall remain in current mode and DMI shall
display cab not active.
 Before inserting BL key, please ensure Light engine / formation and L/NL
switch is in desired position.
 Whenever, BL key is re-inserted in the same cab, this DMI shall become
active and previous state retain.
 If BL key is inserted in other cab, the TCAS shall switch to “stand by”
mode and follow procedure as per clause (STARTING UP PROCEDURE OF
TCAS) to start train.

4.5 Shunting Operation Procedure

Shunting mode is provided to perform shunting operations in Yard. In this operation,
TCAS monitors only maximum speed limit allowed in shunting operations.

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4.5.1. TO PERFORM SHUNTING .

 Press “SHUNT” button followed by “CNFM” button.
 Loco pilot can perform shunting and TCAS shall monitor 15kmph as MPS during this
mode.
 Station equipment will keep monitoring location of shunting and in case find shunting in
non-permitted area, SOS will be sent and EB will apply
 After completion of shunting, press “SHUNT” button followed by “CNFM” button
again. System will change over to “STAND BY” mode. Follow start up procedure to
come to normal mode
 The DMI shall display the default train length and deceleration constant (DC).

4.6 Isolation Procedure At any point of time, If Loco Pilot wants to isolate TCAS
system, keep the isolation switch (provided near TCAS control unit) in isolation position.

1. Ensure DMI is showing isolation mode and TCAS is not applying any type of Brake.

2. If TCAS is applying any brake even after TCAS Isolation, keep EB bypass cock in
close position.

3. To Exit from isolation, first ensure EB bypass cock is opened and keep
isolation switch in normal position. TCAS goes to standby (SB) mode.

4.7 Non-Leading (Multiple Locos)/ Banker Operation Procedure

Non-leading mode is provided to perform locomotive movements in multiple unit or
banker operation. In this mode, TCAS doesn't provide any type of train protection.
To enter into this mode, keep leading/ non-leading switch in non-leading position in
both cabs/ Desks when locomotive is in standstill. Ensure non-leading mode is
displayed on DMI. To exit from this mode, keep leading/ non-leading switch in
leading position in both Cabs/ Desks when locomotive is in standstill.
If the leading/ non-leading switch is placed in different positions in different Cabs/
Desks, TCAS gives “both leading and non-leading inputs are Active” message on
DMI. At this point, TCAS retains valid previous combination

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4.8 Reversing Procedure

Reversing procedure enables Loco Pilot to perform back movements without changing
the CAB/ Desk for small distances. For moving to long distances, use Shunt Mode.

For selecting reverse mode, Press 'REV' button on DMI, when Train is at standstill. In
Reverse mode TCAS monitors REV mode speed limit. If Loco Pilot moves Train in
forward direction, REV mode exits automatically. Reverse mode speed limit (30 kmph)
and distance (500 m).
TCAS exit from reverse mode to SR/ LS mode, when Loco Pilot selects SR
mode or Reverser is kept in Forward direction or 500 m crossed in Reverse mode.
If Loco Pilot wants to continue further in Reverse mode, it selects 'REV' button on
DMI.

4.9 Train Trip Recovery Procedure and SPAD

Whenever Train crosses Movement Authority (MA), TCAS enters into TRIP mode. In
this mode, EB shall be applied and Trip Counter will be incremented. To release brake,
Loco Pilot has to acknowledge train trip by selecting 'P_TRP' button on DMI. Then

TCAS enters into Post Trip (PT) mode. In this mode, only PT mode speed limit is
supervised by TCAS. Loco Pilot has to select SR mode or Reverse (RV) Mode to come
out of P Trip mode, till that time, it remains in post trip mode only.

4.10Over Riding Procedure (Signal or Station TCAS Failure)

There may be cases where Track side signals may get failed or station TCAS may be
faulty. In these cases, Loco TCAS doesn't get movement authority.

When Track side signal is faulty, follow regular operational procedure to cross the signal
at Danger. If TCAS is giving MA beyond the faulty signal, Loco Pilot proceeds with Train

movement and if TCAS is giving MA up to the signal, then follow below procedure:
Select 'OVRD' button on the DMI to override signal at Danger.

Overriding is allowed only when Train is within 200 m from the signal and standstill.
After selecting override, Loco Pilot has to cross the signal in 255 seconds. In Override

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Mode, speed limit (30kmph) will be supervised.

After crossing the override signal TCAS will go to Onsight mode.

Onsight mode continues up to the next signal crossed other than danger. If Next signal
crosses Danger, TCAS prompts for repeated override acknowledgment. If Loco Pilot
fails to acknowledge in stipulated time, TCAS applies Brake.
TCAS follows special procedure for overriding of LSS and Gate signals. After crossing
these signals, TCAS goes to Onsight mode, but after passing 100 and 250 m
respectively in Onsight mode. TCAS will now go to LS mode and prompts for Loco
Pilot Acknowledgment. If Loco Pilot fails to acknowledge in stipulated time, TCAS
applies Brake. (For above signals, next signal will be considerably far away, so that this
special handling is done). MA is acquired by Loco TCAS.

4.10.1 Procedure for passing signals at ”ON”

A.HOME OR STARTER SIGNALS.
 After getting authorization from ASM,
 The loco pilot to press “OVERRIDE” button followed by “CNFM” button
at Stan, The loco pilot need to pass the signal in 255 secs.
 On passing over a RFID tag at foot of signal, the equipment shall come to
“ON SIGHT” mode and the permissible speed up to next signal be 15 kmph.
 Loco pilot must check the track ahead is free, point correctly set and respect
existing signaling arrangements as per existing directives.
 TCS will change to “NORMAL “mode on crossing the next signal; if the
signal is in OFF condition and MA is received from station TCAS,

B. ADVANCE STARTER.
 After getting authorization from ASM, LOCO PILOT to press” OVERRIDE
”button followed by “CNFM” button at standstill. The loco pilot need to pass
the signal in 255secs.
 On passing RFID TAG AT FOOT OF LSS, the TCAS shall prompt loco pilot for
“SR”mode.if”R” button is pressed followed by “CNFM” button, the
equipment will come to “SR” mode will permit full speed else brake shall be
applied.
 The equipment shall come to normal mode after passing 2 RFID tags and
communication with next station.

C. IBS signal
i) Loco pilot has taken ASM permission with PNO.

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 Some procedure as per advance starter in (b)

II) Loco pilot is not able to talk to ASM
 Loco Pilot press ’OVERRIDE’ button follow by “CNSM” button at standstill. The
Loco Pilot need to pass the signal in 233 Secs.
 On passing RFID tag at foot IBS, the loco pilot shall press “SR” button followed by
“OVRD” button. The equipment will come to “ONSIGHT” mode and the
permissible sped up to next stop signal shall be 15 kmph.
 On passing next stop signal in OFF condition, the equipment shall come to normal
mode.

D. Gate Stop signal

 After getting authorization from gateman or otherwise as per operating procedures,
Loco Pilot to press “OVERRIDE” button followed by “CNFM” button at standstill,
the loco pilot need to pass the gate signal in 255 secs.
 On passing over a RFID tag at foot of gate signal, the equipment shall come to “ON
SIGHT” mode and the permissible speed up to gate shall be 15kmph.
 After passing the gate RFID, the equipment shall come to normal mode when it
receives MA by gate TCAS.

E. PROCEDURE FOR PASSING “WHEN CALLING ON SIGNAL IS TAKEN OFF:

 After stopping at ON with train on track, once ASM takes off calling on signal,
necessary display will appear on signal aspect with line number for which route
is set including MA,
 Loco pilot can pass the signal and MPS after passing calling on signal shall be
15 kmph up to next signal,
 In case line is occupied with a TCAS equipped train, MA shell only be up to
rear of train and TCAS shall prevent rear end collision, however, it will be the
responsibility of loco pilot to in case of any obstruction.

F. PROCEDURE for recovery from TRIP MODE;

 Do not isolate TCAS.
 Press the “P-TRP” button followed by “CNFM” button to exit from the
TRIP mode, EB is now released and train comes to post trip (PT) mode.
 System shall prompt for either “reverse” mode or” override” in case of
other then LS Sand ”SR” in case of LSS.
 In case of reverse mode selection, train can be backed after ensuring extant
operating procedures upto 200 meters to come up to signal passed at”ON”
and thereafter can be moved in forward direction in SR mode following

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instruction from station.

 In case of selection of “OVRD” button. The train shall come to “ON
SIGHT” mode and MPS shell be 15 kmph till next stop signal.
 In case of LSS ,it will go to “SR” mode and follow procedure
 Make entry in log book.

G. EVENTS when a signal is put back to “ON” on approach.

 The MA shell abruptly reduce. In case train is not able to stop before signal,
the TCAS will go to TRIP mode. EB is applied and the train will stop.
 Follow post trip instruction as per( procedure for recovery from TRIP MODE,)
 To restart the train, follow all prescribed procedures under G&SR and other
relevant ruler.
 Make entry in the log book.

H. STEPS TO BE TAKEN IN CASE OF TCAS SYSTEM FAILURES

(A) In case of IRDMI failure, the IRDMI screen display will be blank.
 EB is initiated automatically and train will come to a stop
 Isolate TCAS as per TCAS ISOLATION PROCEDURE
 Make entry in the log book.
(B) System failure icon flashes in the IRDMI
 EB will be applied. SF icon will lit
 Isolate TCAS as per TCAS ISOLATION PROCEDURE
 Make entry to the log book.
(C) Signal showing “OFF” but MA not available
 Consult ASM/gateman for any abnormal situation.
 If ASM confirm that everything is OK, take TCAS to “SR” mode by pressing
“SR” button followed by “CNFM” button
 Start the train and after passing few RFIDs, the sytem will come to normal
mode.

I BREAK APPLICATION DUE TO ROLL AWAY PROTECTION

 Do not isolate TCAS
 After train stops, press “CNFM” button and break shall be release. The TCAS
will continue in normal mode & proceed further with TCAS working.
 In case breaks not released, isolate TCAS as per TCAS ISOLATION PROCEDURE
 Make entry in log book.

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5. SOS - GENERATION AND RECEPTION

5.1 Self- Loco generated SOS

5.1.1 Manual SOS Whenever Loco Pilot detects an Emergency situation and wants to alert
other trains, Loco Pilot can generate manual SOS by pressing 'Common' and 'SOS'
buttons on DMI panel simultaneously. On pressing these buttons, Loco TCAS broadcasts
SOS message. As long as SOS is active, Loco/ Train speed is restricted to 30 kmph.
To cancel SOS, Loco Pilot has to press 'Common' and 'Ack/ Cancel' buttons on DMI
panel simultaneously.

5.1.2. Block stop SOS Whenever Train stops in Block with MA greater than 500

m, TCAS treats it as abnormal situations. TCAS asks Loco Pilot to acknowledge

Block stop by pressing 'Ack/ Cancel' button on DMI within 15 seconds.

If Loco Pilot fails to acknowledge within 15 seconds, TCAS broadcasts SOS message.
SOS cancels automatically, when train is moving or Loco Pilot acknowledges Block stop.

5.2 Other Loco generated SOS

Whenever Loco TACS receives SOS from other Locos, which are approaching towards it
and in a distance limit of 3 km, Loco TCAS treats this as Emergency. If either Loco TCAS
direction or other loco direction is unknown, Loco TCAS considers this SOS as long as other
loco communicates SOS.Loco TCAS first applies brake so that Loco/ Train comes to stall
first, then 30 kmph speed limit is supervised.SOS condition cancels when other Loco
says No SOS or Loco / Train crosses SOS generated location or No communication
from other Loco for 1 min/ 3km whichever is earlier.

5.3 Station generated SOS

Whenever Loco TACS receives SOS from station, which is in a distance limit of 3 km, Loco
TCAS treats this as Emergency. Loco TCAS first applies brake, so that Loco/ Train comes
to stall first, then 30 kmph speed limit.

SOS condition cancels, when station says No SOS or Loco/ Train passes away by 3

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km from station or No communication from station for 1 min/ 3 km whichever is

earlier.

6. CREW MESSAGES
1. System fault, isolate or restart TCAS
2. Ack Loco stop in block Section, SOS generates in XX s
3. Emergency brake bypassed (EB cock closed), no traction
4. Train tripped, Select P_Trip
5. FSB applied, Dead End Detected
6. EB applied, movement in standby mode
7. FSB applied, Rollback detected
8. Reverse movement not allowed, use REV mode
9. Forward movement no allowed in REV mode, use SR mode
10. Ack SR mode – TCAS Area Exit
11. Ack SR mode – Radio Comm Fail with Station
12. Ack SR mode – No Section Speed Info
13. Ack LS mode – Radio Comm Fail with Station
14. Ack LS mode – No Section Speed Info
15. Ack Repeated Red signal Override
16. Head On with Loco XXXXX in YYYY m
17. Rear End of Loco XXXXX in YYYY m
18. Override selected, cross signal in XXX s
19. Reverse Mode Expires in XXXXm or YYY s
20. Manned LC Gate XXXX approaching in YYYY m
21. Unmanned LC Gate XXXX approaching in YYYY m
22. LS mode waiting for radio comm with station
23. LS mode waiting for section speed Info
24. Both leading & non-leading Inputs are active
25. ABT is pending, acknowledge in XX s
26. ABT in progress
27. ABT Success (DC – X.YY m/s2)
28. ABT Fail (DC – X.YY m/s2)
29. ABT Aborted
30. MBT not allowed in this section
31. MBT in progress
32. MBT Success (DC – X.YY m/s2)
33. MBT Fail (DC – X.YY m/s2)

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34. MBT aborted

35. Train length computation in progress
36. Train length computation success (XXXX m)
37. Train length computation fail (XXXX m)
38. Train length computation aborted
39. Turn out in XXXX m with speed limit YYY kmph
40. TSR in XXXX m with speed limit YYY kmph
41. PSR in XXXX m with speed limit YYY kmph
42. End of authority in XXXX m
43. TCAS area entry
44. System Self test success
45. System self test fail – XXXX
46. Brakes Testing – waiting for MR X.YY( X.YY) Kg/cm2
47. Bakes Testing – waiting for BP X.YY(X.YY) Kg/cm2
48. Brakes Testing – NSB applied, BP-X.YY Kg/cm2
49. Brakes Testing – FSB applied, BP-X.YY Kg/cm2
50. Brakes Testing – EB applied, BP-X.YY Kg/cm2
51. Brakes Testing Success
52. Brakes Testing Fail (NSB,FSB, EB)
53. Brakes Testing Fail, press ACK for Re test Brakes
54. Select Train configuration, press config button
55. Select Staff responsible or shunt mode

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TCAS ON SOUTH CENTRAL RAILWAY