One of the few (or rather the only) explanation I can find on the “Set number” is from TrainWeb.org
Another number which appears on the train is the “set number”. This is displayed at each end of the train to identify its duty in the timetable. The number is set up by the crew preparing the train for service and it is retained by that train as long as it works that particular path in the timetable for that day. It provides a useful means of quickly identifying trains and is used whenever reference made to particular service trains.
So long story short it’s a train number like “Pelham 123” basically identifying the route the train is running today including line and schedule, though if you feel like a project you can take a look at data from Trackernet to figure it out.
Credit:stackoverflow.com‘
4 Mar, 2024
4 Mar, 2024