If you are a fan of Indian Railways, you may have noticed some small yellow lights or square-ended arms below the main stop signals on the tracks. These are called shunt signals, and they are used to control shunting movements of locomotives or trains.
Shunting is the process of moving trains or locomotives from one track to another, or coupling or uncoupling them, within the station limits or the yard. Shunt signals allow the drivers to proceed past the stop signals with caution for shunting purposes, even if the stop signals are at ‘on’.
Shunt signals have two indications when on, they show the same indication as the stop signal above them, which means stop dead. When off, they show the indication of proceed slow for shunting, which means the driver can move ahead with caution, being prepared to stop for any vehicle or obstruction ahead.
Shunt signals are placed on a post by themselves or below a stop signal other than the first stop signal of a station. They are not used for normal running movements of trains. They are also not pulled off when the stop signal is not on, or when a calling-on signal is below them.
Shunt signals are an important part of the signalling system of Indian Railways, as they help in efficient and safe shunting operations. They also add to the visual appeal of the railway tracks, especially for the railway enthusiasts who love to observe the different aspects and indications of the signals.
