slow speed control
noun1
Rail transport, Railways, Transport An electronic device fitted to locomotives which enables them to operate at a very slow speed when their train is loaded or unloaded on the move.
- Slow-speed control was fitted to Class 37/7s in South Wales, to permit diagramming on the coal circuits between pit and power station.2020 December 16, David Clough, “Class 37s at 60: the great survivors”, in Rail, page 56, photo caption: