07-05-2016, 07:42 PM
(05-09-2009, 04:45 PM)PJW Wrote: Occasionally might be used to protect incidents or severe emergency speed restrictions- but again this probably was invoked more in times past than current day. I think that we wouldn't continue to provide the facility if it were not inherently built into SSI and thus all but "comes for free".
We use it in complex areas if there is a speed restriction and multiple routes up to it which would mean a huge number of ATP routes needing speed restriction chips.