So I'm using aws, and its a game changer. I'd love to use the rest, but how do they work? What are the rules etc?
The only other system on UK trains is DSD/DVD (vigilance devices). These sound an alarm every 30 seconds or so and the driver must respond to it to prove they are in control/paying attention. These can be activated by panels in most locomotives (or via the switch cabinet behind the driver in the class 66). Some locos do not have DVD/DSD though (older locos).
You also have tpws. Which will apply the emergency brake if you pass a signal at danger (useless on tsw) but also it will apply emergency brakes if you are approaching a speed limit reduction too fast and in some cases approaching a signal with approach control to fast. Some cases you are required to push the train stop override button. There is a scenario on bcc where you do this to pass a signal at danger.
