Why does a passenger train have exactly three lights “on the tail”? (3 photos)

The last car of the passenger train is equipped with three red lights. The point here is this.





This is necessary so that the driver can see the train ahead. BUT for employees, this is a sign that the car is really the last and nothing was unhooked from the train along the way.

Before the cars were equipped with electricity, the function of the lights made candle lanterns. When moving forward, they glowed red, if the wagons were settling down - the white light was on.



So why exactly three lights?

This is the marking of a passenger train. The fourth lantern is already here and not needed. And at stations with a large track development, the driver immediately sees where the wagons are: on his site, or on the neighboring one. plus three of a lantern do not merge with mast and shunting traffic lights.



Such marking is not only for standard passenger trains, but also for Sapsan trains.