In the Class 375/9 on Southeastern Highspeed (TSW2) there is a "Brake Hold" button on the side of the power/brake handle. What does it do?
#What does Brake Hold do in Class 375 9?
terse tapir
subtle wyvern
It holds the brakes on
terse tapir
ight
subtle wyvern
Like it says
If you hold it when your throttle is in a brake position and move it to neutral it'll hold the brakes on
kindred birch
It's supposed to be use to prevent train rollback in case you start on a gradient.
Usually given that the brake don't release instantaneously, if you are on reasonably flat ground you can safely start the train by moving the controller from step 3 brake to power 1 or 2 (maybe hesitate a little on idle).
In case you are on a more significant gradient and need the brakes to be applied for a little longer, you can put the throttle to a brake position (1 should be sufficient to hold the train), then press and hold the "brake hold" button, and release it after you are in the power notch you want to use for departure, the brakes will remain applied until you let go of the button.
TL; DR: It allows you to use the train brake like you would use the handbrake for Hill starting a car