Shunt Signal (G.R. 3.14)

  • A shunt signal is a subsidiary signal provided to control shunting movements.

  • A shunt signal may be placed on a independently or below any stop signal except FSS.

  • When it is placed below a stop signal, it shall show no light in 'ON' position; the aspect is STOP and indicates stop dead.

  • When it is placed independently, it shall show two white lights/yellow lights horizontally in 'ON' position; the aspect is STOP and indicates stop dead.

  • When it is placed below a stop signal in 'OFF' position, it shall show TWO WHITE/YELLOW lights OBLIQUE/DIAGONALLY; the aspect is Proceed Slow and indicates proceed with caution for shunting.

  • In case the shunt signal becomes defective, the authority to pass defective shunt signal is T/369 (3b) and proceed hand signals. Setting and locking of points over the route shall be ensured either by clamping or cotter bolt.

Types of Shunt Signals

  • Disc type shunt signal

  • Miniature semaphore arm

  • Position light type shunt signal

Note: Normally, position light type of shunt signals are provided in colour light area.

Position Light Type Shunt Signal

  • It is provided in colour light signalling territory.

  • It shall not show any light in 'ON' position when it is provided below a stop signal.

  • It is a box-like arrangement with provision for three miniature white lights.

  • When two lights are burning horizontally, it is 'ON' position (provided independently).

  • If two lights are burning oblique/diagonal, it is 'OFF' position (provided independently or below a stop signal).

  • The arrow mark on the top of the box indicates the line to which it refers.

Shunting Permitted Indicator (S.R. 3.14.3)

  • It is an appliance that works in conjunction with the stop signal and is provided to control shunting movements.

  • It shall be placed on a post by itself only.

  • It can permit shunt movements in both directions.

  • It is provided in the non-interlocked area of the yard where the interlocked area is isolated.

  • Normally, it can be operated by a ground lever or through panel.

  • It shall not show any light when shunting is not permitted.

  • When shunting is permitted, it shows a yellow cross light in both directions during day and night.

  • When shunting permitted indicator becomes defective, authority to pass defective indicator is T.369(3b) plus proceed hand signals (PHS).

  • Detailed instructions regarding the working of SPI are available in SWR.

Back to Operating Material