ELECTRIC BLOCK INSTRUMENT/ OBJECTIVES OF ELECTRICAL BLOCK INSTRUMENT (BWM-1.05)
1. The object of signaling trains by Electrical block Instruments is to provide, at all times a visual indication of the Block Sections to which they refers and to guard against two trains being admitted into a block section at the same time.
2. Each Instrument is connected to a similar instrument at the next block station and the two block instruments work together.
3. The pair of instruments is used for working of both UP and DN Trains over the block section so that each is used both for sending train to the next station or receiving train from the next station.
4. Each section controls the line by which trains approach it and the line by which trains leave it, is controlled from the station at the other and of the block section.
BLOCK INSTRUMENT USED IN CENTRAL RAILWAY ON DOUBLE LINE- (BWM-1.09)
I. SGE lock and Block Instrument/SGE lock and Block Instrument interlocked with axle counter.
II. Daido’s token less block and block instrument.
III. Block proving Axle counter(BPAC)
SGE LOCK AND BLOCK INSTRUMENT:-
1. This block instrument is provided with a telephone. It can be Interlocked with axle counter. The important parts of this block instrument are Bell plunger, commutator, key, bell etc. It has two glass windows at its upper portion which is called the Receiving Indicator and is for the purpose of indicating the signal received from the station in advance. It has three indications ‘line closed’,“line clear” and “Train on Line”. And is fitted with a needle which may point to any of the tree indications. The upper window is the receiving Indicator and it indicates the signal given by the station in advance.. When the SM of station in advance rotates the commutator, the needle of the receiving window shall change accordingly.
2. The lower window is sending indicator. The needle of the sending indicator indicates the signal send by the SM to the SM in the block station in near i.e the sending indicator corresponds to the Receiving Indicator of the station in advance.
3. It is interlocked with the last stop signal.
4. When line clear had been granted earlier and the commutator turned to indicate “Train on Line”, the commutator remains locked until the signaled train has passed over the section clearing track circuit and the Home signal returned to normal positions and BPAC is showing section-clear Indication where BPAC is provided.
5. In case station master observer that he cannot turn the commutator to “line closed” position from “Train on Line” position due to either failure or non-operation of track circuit/BPAC he shall inform the SM in near on telephone and exchange Pvt. No. There after line clear shall be obtained on electric communication instruments. The SM in rear will issue an authority to the Loco Pilot on form T/369(3b) to pass the last stop signal at ON position.
DAIDO’S TOKENLESS SINGLE LINE BLOCK INSTRUMENT
1. It is a Tokenless block and block instrument used on double line. It shall not be possible to Take OFF the Last Stop Signal until line clear has been received on the Block instrument.
2. The most important parts of this instrument are receiving handed sending handle, PB-1, PB-2, Button shunting occupation key, Bell, telephone, counter etc.
3. The instrument indicates Line closed/Train coming from/ Train going to etc. positions.
BLOCK PROVING AXLE COUNTER (BPAC):-
1. This block instrument is based on Axle Counter. It is push button type.
2. It is operated by the SM of station which obtains line clear.
3. It automatically indicates the ‘Train on line’ position as soon as the train enters into the block section. When the train arrives at the station in advance the block instrument automatically goes to “line closed” position.
4. If the block instrument indicates the ‘Train on Line” position even after the train has reached at the station in advance, it can be reset.
5. The line can be blocked for shunting in block section. 6. Line clear cannot be obtained on this block instrument when it indicates the “Train on Line” or Line Block position.
7. This Block instrument is also interlocked with Last Stop Signal single line SGE Block instrument i.e. it shall not be possible to take OFF the Last Stop Signal until line clear has been obtained on this block instrument.
8. If for some reason the Last Stop Signal cannot be taken OFF or the block instrument is out of order, the SM shall obtain line clear on other electric communication instrument and shall issue T/369(3b) to pass the Last stop signal at ‘ON’ on which the private number of the station in advance, received by him on getting line clear is written.
LOCK AND BLOCK INSTRUMENT ON SINGLE LINE (BWM-1.10)
1. Neale’s Ball Token Instruments.
2. Daido’s single line token less block instruments.
3. Keosan’s single line Token-less Block instruments.
4. Podanur token less Block instruments (push button type)
NEAL’S BALL TOKEN INSTRUMENT:-
1. It is a token block instrument and it is co-operative. It cannot be operated without the co-operation of the SM of the station in advance. The token is extracted only after line clear is received. And the token is given to the loco pilot as authority to proceed.
2. It has an operating handle which controls the extraction of metal token. The Handel has an arrow mark on it to indicate three positions viz. “Line closed”“Train coming from” and “Train Going to”.
3. If the block instrument becomes defective and it is not possible to give token to the Loco pilot, paper line clear ticket (PLC) (T/D 1425DN, T/C 1425UP) shall be issued to the loco pilot. When the last stop signal becomes defective which is not interlocked with the block instrument, T/369(3b) shall be issued along with the token to pass the last stop signal at on.
4. The number of tokens available at any instant in the block instrument can be known in the token window. When the number of token becomes less than five and it is not likely to increase due to large traffic, concerned Signal Inspector / ESM of S&T department shall immediately be informed to make available of token.
INTERLOCKING THE LAST STO SIGNAL WITH NEAL’S BALL TOKEN BLOCK INSTRUMENT. (BWM-5.09)
1. Some block instruments are fitted with such system that the key controlling the advance starter signal can only be removed from the lock when the operating handle of the block instrument turned to the side indicating the ‘Train Gong To’ position . Then only the Advance Starter Signal can be taken OFF.
2. In the event of failure of Block instrument with the handle in the “Line Closed” position the Advance Starter key cannot be released from the Block instrument lock. In such case the SM shall obtain line clear from the station in advance on the electric communication instrument and give the Loco pilot the paper line clear Ticket (PLC) (T/C 1425UP, T/D1425DN) on which authority pass the last stop signal at “ON” is written.
3. If owing to some defect the Advance Starter Signal cannot be Taken OFF although the handle of the block instrument is in “Train Going To” position the SM must give the loco pilot an Authority to pass the Advance Starter signal at ‘ON’ on the prescribed form T/369(3b) along with the token.
DIADO’S TOKENLESS/KYOSAN’S TOKENLESS LOCK & BLOCK INSTRUMENTS (BWM-5.12-13-14)
1. Both the Block instruments are used in Lock and Block system. Both have operating handle and are co-operative i.e. the co-operation of the SM in the station in advance is needed while operating this instrument.
2. The last stop signal is interlocked with this block instrument and taking OFF the Last Stop Signal is Authority to Proceed for the Loco Pilot. If the Last Stop Signal or the Block instruments become defective then the Loco pilot shall be issued the paper line clear ticket (PLC) as Authority to proceed.
PODANUR’ TOKENLESS LOCK AND BLOCK INSTRUMENT
1. It is push button type Block instrument. The co-operation of the SM of the station in advance is not needed while obtaining line clear or clearing the section. So this block instrument is non-cooperative.
2. The co-operation of SM of the station in advance is needed while cancelling the “line clear”.
3. It is interlocked whit the Last Stop Signal and its operation is same as that of DIADO and KYOSAN Block instrument.
4. This Block instrument is used in Lock and block system.
GENERAL REQUIRMENTS OF TOKEN LESS BLOCK INSTRUMETS DAIDO, KYSAN, PODANURBWN-5.12
1. A track circuit of two rail length ahead of the Last Stop Signal is provided to ensure that the Last stop signal is placed to “ON” immediately when the train has entered the track circuited portion. This will cause the “Train on Line” indication to appear on the block instruments of the stations at either end indicating the entry of the train in the Block section.
2. The Last stop signal cannot be taken OFF again, once it has been proved to “ON” position automatically with the passage of the train over the track circuited portion. Station master will ensure that the Last Stop Signal has assumed the ‘ON’ position. It shall not be possible to take ‘OFF’ the Last Stop Signal unless the block section has been cleared by the preceding train and fresh Line clear has been obtained.
3. In case of semaphore signals, operated from a lever frame or electric lever lock provided on the lever of LSS, ensures interlocking of the LSS with the Line clear indication of the block instrument.
4. Two track circuits each of two rail length are provided ahead of the home signal one for proving the Home signal to ‘ON’ immediately the train occupied the track circuited portion and other for giving audible announcement to the station master about the passage of the train engine inside the home signal.
NOTE- If the Block instruments become defective and line clear is obtained on any other means, T/A1425 and T/B1425 shall be issued.
USE OF BLOCK INSTRUMENTS- BWM-1.11
Block instruments shall only be operated by the SM/ASM/Cabin ASM/ Switch man on duty and shall be used exclusively for the purpose of signaling train strictly in accordance with the rules and regulations laid down. Station staff must not interfere with any parts of a block instrument when it is out of order or at any other time.
CONSENT REQUIRED BEFORE INTERFERING WITH BLOCK INSTRUMENTS (GR-14.03SR-14.03-1)
1. Whenever block instruments or their fittings are to be interfered with for testing, repairs or replacement, the competent S&T staff shall issue a Disconnection Memo on prescribed from T/351 to the station master clearly specifying the various signals which shall be affected during such repair or replacement.
2. The SM shall not give his consent for this purpose, unless block section is clear of trains and the block instruments, where provided have been brought to ‘Line Closed’ position.
3. After the testing of the block instrument and signals has been completed and the reconnection memo received from S&T staff, the block instruments shall be brought in use and normal working resumed.
4. If a train is waiting at station to proceed, the block instruments or signals shall not be tasted by S&T staff, unless it has been so authorized in writing by the SM who before giving such permission shall inform the driver of the waiting train in writing to treat the signal/signals as defective.
CERTIFICATE OF COMPETENCY- GR-14.04
No person shall operate the Electrical Block Instruments until he has passed a test in operation of Block Instruments and unless he holds a certificate of competency T/115B granted by a railway servant appointed in this behalf by Railway Administration.
DUTIES OF STATION MASTER WHEN BLOCK INSTRUMENTS BECOME DEFECTIVE
1. Neither the SM nor any other station staff should interfere with the block instruments when it gets defective. Proper care must be taken to prevent dust; grease etc. on the block instruments and nothing should be kept on the battery box.
2. SM shall inform the S&T department immediately when block instruments become defective.
3. The section controller must be informed about the same.
4. SM should endorse the defective conditions of the instrument in the S&T Failure register.
5. Line clear shall be obtained or given on Block Telephone/Control phone or any other approved means of communication until the block instrument is ready to work.
6. The station master who gives line clear shall inform the SM who is getting line clear about the last two trains just left his station and the two trains which have just arrived at his station with time. The SM at other end should also follow the same.
7. When the block instrument becomes defective the description of the train should be mentioned in T/A 1425 or T/B 1425 as per the situation.
8. When the block instrument becomes defective the Last Stop Signal is also treated as defective.
9. When line clear is obtained on the approved communication instruments, on double line T/369(3b) and on single line paper line clear ticket (PLC) shall be issued to the Loco pilot as Authority to proceed.
10. The SM shall not permit the station staff to interfere with the block instrument until he gets the disconnection memo from the S&T staff.
11. The block instruments and signals shall not be brought in use until the block section is clear.
12. When the block instrument and block telephone become defective, while obtaining line clear on station to station fixed telephone/ Railway Auto Phone/ BSNL, MTNL telephone, the station masters on either end shall verify the private no. and time of last three train and then line clear shall be obtained on that means of communications.
LINE CLEAR SHALL BE OBTAINED ON CONTROL TELEPHONE IN THE FOLLWING MANNER:-
I. SM shall ask the section controller to get line clear form the station in advance.
II. On getting the information from the station master, the SOCR shall call both the SM on phone and ensure the private no. of the last three trains with time. After being satisfied that the block section is clear he shall obtain the Line Clear from the SM from the station in advance. He shall enter the private number and name of the station master giving line clear on the control chart.
III. The section controller shall say the name of the SM and private no. which he has obtained on getting line clear, with T.C No./T.N number.
IV. On getting line clear from the section controller the trains shall be dispatched on proper authority and the same will be mentioned in the TSR.
SURRENDER OF TOKEN BY LOCO PILOT:-SR-14.11.2
1. The loco pilot of a stopping Mail/Express, Passenger or Parcel train, on arrival of the block station in advance, shall through the token-pouch on the platform cautiously near the station office. For all other stopping trains, the Loco pilot must make over the token to a member of the station staff in uniform on coming to a halt.
2. If train runs through the station without stopping the token with the pouch must be dropped by the Loco pilot into the net provided for the purpose.
GIVING TOKEN TO THE LOCO PILOT:-
A-if train stops at the station:-
1. Token shall be given to the Loco pilot of all passenger train and parcel train near the station masters office provided that the Loco pilot has surrendered the token which he has received at last station in rear.
2. For all other trains stopping at the station, the token shall be issued to the loco pilot by a member of station staff on coming to a halt. The token for the next block section shall be given only when the loco pilot surrenders the token of block section in near.
B- Train running through the station:-
1. The token is fixed in a line clear hook and put in stand provided for the purpose and station staff stands at this stand until the loco pilot takes the token. At night a white light is lit at this stand which indicates the engine crew about the line clear.
2. STATION WHERE LINE CLEAR HOOK IS NOT PROVIDED:-
a. Token shall be given to the loco pilot of the train by putting the token in the pouch of line clear hook at the facing point. b. For the train which runs through the loop line the token shall be given by putting it in the pouch of line clear hook near the station masters office.
ENTERING THE BLOCK SECTION WITHOUT AUTHORITY TO PROCEED ON WITH WRONG AUTHORITY - SR-14.11-1
1. If a loco pilot who has entered the block section with correct token or line clear ticket or authority to proceed without line clear, losses the same on the run, he shall proceed to the next station and report the matter to the station master.
2. Should the loco pilot enter block section without a token not applicable to that section, he shall at once stop the train and advise the Guard and take immediate steps to protect the train in front and advise the Guard to protect it in rear. The Asst. Loco pilot shall be deputed to take the token with a note explaining the circumstances to the nearest station.
3. If the token is sent to the station immediately in rear the station master shall deliver the Asst. Loco pilot a correct token for the train to proceed to the next station.
4. Should the token be sent to the station ahead the station master shall immediately inform the station at other end of the block section of the circumstances and hand over the Asst. Loco pilot an Authority to proceed without line clear to enable the train to come to his station. On arrival of the train the SM shall inform the station at other end of the block section by a message, supported by a Pvt. No. , of the complete arrival of the train at his station.
5. Before starting the train forward with the correct token or authority to proceed without line clear the Loco Pilot and Guard should remove the detonators placed on the line for protecting the train.
6. If the loco pilot over carries a token beyond the section to which it applies and is in possession of the correct token for the section he should proceed with his train to the station ahead and hand over the wrong token to the station master and obtain a receipt for it. The SM shall return the token to the station concerned with the Guard of the first train in that direction and obtain a receipt form it.
BELL CODE OF BLOCK INSTRUMENT GR-14.05 (BWM-4-10)
Note- “O” indicates the beat on strokes and “----“ indicates the pause.
a. No other signals shall be used other than the prescribed signals and a copy there of shall be exhibited in each block station near the place of operation of the block equipment.
b. Each beat shall be given slowly and distinctly,. While giving the beat, the beat plunger should be pressed for one second other the signal will be lost on indistinct. The direction of each pause should be equal to the time for two beats.
c. The above mentioned bell code shall not be applicable to these sections where Block proving Axle counter (BPAC) or track circuit is provided and in the total track circuited yard except running line.
ACKNOWLEDGEMENT OF BELL CODE SIGNALS:-
1. Each signal received shall be acknowledged by sending its authorized acknowledgement.
2. No signal shall be acknowledged until it is clearly under stood.
3. A signal shall not be deemed to be complete until it is acknowledged.
4. If a station to which signal is sent does not reply the signal shall be repeated at interval of not less than 20 seconds until reply is received.
5. If the acknowledgement of any bell code is not received immediately then it should be entered in the remark column of train signal Register.
