Passenger Trains > Flashing Green Signal

I saw a flashing green signal coming into the Broadway Station of the Denver RTD light rail today. This was the first type I saw a signal of this type either light rail or heavy rail. What does it mean?

NORAC (the rules that Amtrak uses) describes a high flashing green as Cab Clear. Which ether means an 80 MPH divgering route if your CaB Signal also displays this. Or if your cab signal readout displays something else. To go by the display on your Cab Signal.

We have something similar in San Diego on the Trolley light rail Orange Line

"San Diego Trolley light rail system Rule 4.5.9 is established to identify the use of a flashing green aspect to indicate a route alignment through the respective interlocking and that all block signals are clear to the next interlocking signal. This aspect will be a default indication for freight train operation at designated interlocking signals on the Orange Line where minimmum block signal spacing exists to enhance trolley operation."

Basically, we shortened the blocks to handle more light rail trains and the freight would not be able top stop in time if they maintained any speed and also because of the grade. They will get a flashing green that will indicate the next three blocks (I think that is how many blocks are now in between the affected Interlockings) are clear ahead. Anything other than a flashing green signal at the first interlocking shall be treated as a stop indication. After getting permission to pass the improper signal indication they will run at restricted speed and be authorized one signal block at a time. If a light rail train receives a flashing green signal it will be an acceptable signal but the Controller (Dispatcher) must be notified immediately.

We have the same signal indications up here on the Los Angeles to Pasadena MTA Gold Line.
At each signal location, usually an interlocking point or set of crossovers, is a set of signals facing each way displaying the following constantly lighted (lit!) lenses.

Normal: Red over Dark over Red > STOP

Approach: Dark over Flashing Green over Red > Proceed Clear

Diverge: Red over Flashing Green over Dark > Crossover lined to other track


This is just my observation of the system as I have watched it.
Anybody out there knowing the basis of this system please speak up!

Then there is the Los Angeles-Long Beach Blue Line signals.
Followed by the Green line's separate 'Airport Signals' designed to be run over by airplane tires. Well, in the pavement, that is!

Jim Baker -- watching those signals --
Whittier, CA

Thanks for the info. This is the same junction that Cozephyr posted a picture of on the western board, a C line train passing on the outside track. That was the same track my D line train used. Northbound, the trains used the inside track. The middle track appears to be available when the I-25 trains head back south when that part of the line is finished.
The Broadway Wye is interesting. The north leg is double track, the west leg triple track and the south leg single track. The north and south legs are in grades no heavy rail train could tackle.