What is VCD and how it work?
What do you find out when you google "what is a vigilence control device"?
Do you know what a "dead man's switch" is?
One of the best known examples is the ' Dead Man's Handle ' as used traditionally on many Diesel and Electric trains .
Driver has to keep a handle or treadle depressed whilst driving . If driver releases pressure then first a warning siren sounds , then a partial brake application is automatically made and then a full brake application if driver does not respond .
Many variants . There is normally a procedure which allows driver to release handle/ treadle briefly without triggering the alarm and braking so as to be able to do necessary tasks away from the driving position .
That is the traditional system . Modern trains have much more complex integrated safety systems .
From where you learn it?
You were already given a good starting point: "What do you find out when you google "what is a vigilence control device"?"
We can't do your work for you - you've posted question after question after question without having put in the tiniest piece of effort. This helps neither you nor us.
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