Poorva Express: हुगली सी बहती तेरी चाल है पूर्वा तू बेमिसाल है - Keshav Singh

Uses of some symbol used by IR.
1.Termination Indicators(pic1)- T/P, T/G, or T/BOXN (painted on a yellow circular board) : Termination of speed zone for, respectively, passenger trains, goods trains, and goods trains with BOXN wagon rakes. In urban areas similar signs such as T/EMU, T/EMU-9, etc., may be seen (termination of speed limit for EMU rakes, EMU rakes with 9 coaches, respectively). Other termination indicators seen include T/PG (for both passenger and goods trains, seen on ECoR), T/P24 (for 24-coach or longer passenger trains), and T/L (for local, i.e., suburban trains, usually EMU or DMU trains). The Hyderabad area MMTS system uses a T/M sign for its trains. T/R is sometimes seen for railbuses. Occasionally, the sign T by itself is...
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shown to indicate a termination of speed limit for all trains. A T/Raj sign was in use for Rajdhani trains when they were first introduced but is no longer used now. WR used T/Raj indicators for the 8-coach Bombay - New Delhi Rajdhani, and its EMUs used the same sign as a termination indicator.
2.Whistle Indicators(pic2)- 'W', or 'W/L' on a square yellow board. The 'W' is a general whistle indicator while the 'W/L' stands for Whistle for Level Crossing. The latter is also seen in Hindi with the characters 'see/pha' == 'seetee bajao - phatak'). Usually provided on approach to unmanned level crossings (and for manned level crossings without a clear view) about 250m away from the level crossing. Similarly, a 'W/B' sign is seen (less often) on approach to a bridge
3.Caution Order for Tunnel(pic3)- 'C/T' in black on a round yellow board. Caution Order in effect inside a tunnel; the sign is placed just outside the entrance to the tunnel. It is not known if this sign is used on any railway other than on Konkan Railway.

Termination Indicators
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T/P, T/G, or T/BOXN (painted on a yellow circular board) : Termination of speed zone for, respectively, passenger trains, goods trains, and goods trains with BOXN wagon rakes. In urban areas similar signs such as T/EMU, T/EMU-9, etc., may be seen (termination of speed limit for EMU rakes, EMU rakes with 9 coaches, respectively). Other termination indicators seen include T/PG (for both passenger and goods trains, seen on ECoR), T/P24 (for 24-coach or longer passenger trains), and T/L (for local, i.e., suburban trains, usually EMU or DMU trains). The...
more...

Hyderabad area MMTS system uses a T/M sign for its trains. T/R is sometimes seen for railbuses. Occasionally, the sign T by itself is shown to indicate a termination of speed limit for all trains. A T/Raj sign was in use for Rajdhani trains when they were first introduced but is no longer used now. WR used T/Raj indicators for the 8-coach Bombay - New Delhi Rajdhani, and its EMUs used the same sign as a termination indicator.
source:IRFCA