PERTIS

In the ticketing system of the British rail network, a Permit to Travel provisionally allows passengers to travel on a train when they have not purchased a ticket in advance and the ticket office of the station they are travelling from is closed, without incurring a penalty fare.

Since a large proportion of rail passengers travel without having their tickets checked at any point of their journey—particularly at off-peak times when stations are more likely to be unmanned—the obligation to possess a Permit to Travel allows the collection of at least some revenue from passengers who would otherwise travel for free.

The system, known officially as PERTIS (Permit to Travel Issuing System), was first introduced by Network SouthEast in November 1988 on the LTS route between London Fenchurch Street and Shoeburyness. The machines, which closely resemble those found in pay and display car parks, were manufactured by Almex Control Systems. Machines were given the designation AS-9 (wall-mounted) or AS-88 (mounted on a metal base), but internal workings and tickets were identical in each case.

Penalty fare schemes spread across Network SouthEast in subsequent years, with AS-88 machines being used exclusively; railway stations in the West Midlands and West Yorkshire PTE areas subsequently had schemes put in place, and machines were installed accordingly.

The front panel of the machine has two LCD displays; one shows the current time, while the other displays the amount paid when coins have been fed in. A button is pressed to print the permit, which shows a serial number, the station name, the date and time. The passenger is supposed to insert coins as near to the value of the fare as possible (if they know the fare and have enough coins), and some machines have a list of common local single and return fares.

Permits to travel bear the warning that they are not fare tickets and must be exchanged for one at the first opportunity. The record of the station of issue means that passengers who travel using it cannot claim that they just boarded the train (allowing them to travel on a cheaper fare) if they are not reached by a ticket inspector until a few stops after boarding. Permits to travel are in any case valid for only two hours from the time shown on them.

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Wikipedia