Or at terminals it would sometimes say x carriages furthest from the ticket barriers at platform x for when a unit at the blocks is detached/locked out.
Thameslink is hit and miss, twice I've gone from St Helier on a Sunday and it says formed of 8 coaches, so I go to the back so I'm closer to the stairs at Wimbledon. On both times, a 4 car 319 showed up instead. I don't know if it just reads 8 cars because it's booked to be 2 x 319?
Probably a mistake. Never known anything on the Wimbledon Loop to be longer than 4 cars on a Sunday.
I say "south-east people" as I would assume SWT display this a lot. However on the electronic boards, what does it say to inform you how many carriages there are on a particular train?
Do the automated announcements (on SWT, at any rate) work off of TOPS, since, if a train is worked by a 450 rather than a 444, they do (usually) say "This train is formed of four coaches" rather than five? So do they refer to what actual stock is working that train?
Is there anywhere in the country where the display shows "This train is formed of 1 coach" (e.g. for a 153). I've not seen that yet!
Normally automatic assuming everything runs as booked, any differences are manual.I believe so. At every SWT station I use, I'd say nearly all services have the train length correctly shown on the PIS displays, whichever TOC runs them, ie at Southampton it shows train length info for any permutation from an FGW 153, through 3 or 4 car 377s from SN, up to an SWT 12 car train. It must be dealt with using live running info, because it is highly unusual to have the 'wrong length' of train appear compared to the PIS.
XC service formations are usually displayed correctly as well, ie as well as 4,5,8,9,10 car lengths they'll put up the coach letters in the right order as well, with comments such as 'bikes in coach D' assuming XC have set the unit up in TRUST correctly.