In article ,
Nick Leverton wrote:

I believe trip cocks were previously fitted to the DMUs on Widened Lines
services, and they seemed to work mostly. I also read on the web that
some (presumably Sulzer) type 2s were fitted for these trains before
the DMUs took over, and also for other LTE workings. Any more gen on
either would be welcome :-)

Tripcocks were also fitted to some steam engines and also the Class 117
dmus working out of Paddington.

David