Page 8 of the CAB1-L manual:
"BIG RED KNOB":
Controls the speed of your locomotive. Turn the
THROTTLE to the right to accelerate, to the left to
decelerate. There is no “stop.”If you don't press a
button or turn the throttle for 30 seconds, CAB-1L goes
into battery-saving “sleep” mode. Turn the
throttle or press any button to “wake” it up.