Thameslink AC/DC changeover.

[Kentish Paul]

I have travelled from London Bridge to St Pancras many times and the changeover has always been at Farringdon. However yesterday a northbound 8 car 377 did the swap at City Thameslink. This was about 15:30.
Was there a particular reason for this or is it something that happens every now and then which i've managed to miss over the years.

 

[Mintona]

It changed a couple of months ago, all northbound trains now change over voltage at City Thameslink. It is in case there are any issues with the change, so the train can still be moved using DC into Smithfield sidings.

 

[C2L]

It changed a couple of months ago, all northbound trains now change over voltage at City Thameslink.

Indeed.

The change came with the December 2013 timetable change.

C2L

 

[swt_passenger]

Another couple of reasons for changeover at City T/L is that for much of the day it would usually be a better station (more space) to tip out a trainload of passengers, and that in the full 24 tph timetable any unit failing at Farringdon would be stuck because the following train would be between stations, and fouling the only possible crossover for the failed train to return south.

Effectively Farringdon is a station too far for flexibility.