Essential for all electrical service.
The maintenance of the signs (Semaphores, signals)
Closure of crossings.
Transmission cables between stations, telephony.
Setting the clocks in the stations.
--------Building service Electric ----------------------------- Post Dispatch ------------
The position switch is a building which includes devices for controlling signals, track equipment, facilities security.
Between 1950 and 1970, the technology position switch is used the position to relay any flexible transit (PRS) with the use of electrical relays in the safety rail in place of combinateurs present in positions of levers routes. They are still present. A PRS is a button routes free from any mechanical locking fitted flexible transit, which all engagements are made using electrical circuits and relay directly into the control apparatus track, provided with electric motors, and signals.
The posts all relay wiring Geographic (PRG) are changing all posts relay (PRS), allowing the equipment of medium and small stations in an economical manner.
Since the late 1970's, this type of job referral team averages stations not remote (or remote controlled exclusively by another PRG) french rail network, with 30 to 100 routes.