Fur Paw

[jeffhergert]

QUOTE: Originally posted by zardoz

QUOTE: Originally posted by CShaveRR

I'm not sure that a dispatcher has any control over the cab signals, any more than he does over intermediate block signals. If he wants a train to stop at a point other than at a signal which he controls (hence the name "control point"--right, MWH?), he still has to tell them.

Carl,
You are correct; the dispatcher has no direct control over cab signals. He can, however, indirectly change the cab signal by, as you pointed out, changing the permissions at Control Points, but that will only effect the cab signals if the train is in the track circuit governed by the Control Point signal (usually two signal blocks).

If your train is close enough for the cab signal to drop out (go to a less favorable indication) if the dispatcher changed an absolute, he has to ask the train to do this. It's not unusual for a dispatcher to ask for a signal back. Sometimes the train may be miles from the absolute, othertimes you wait until your almost stopped, sure that you won't go past the signal before telling the dispatcher he can have it back.
Jeff

[zardoz]

QUOTE: Originally posted by CShaveRR

I'm not sure that a dispatcher has any control over the cab signals, any more than he does over intermediate block signals. If he wants a train to stop at a point other than at a signal which he controls (hence the name "control point"--right, MWH?), he still has to tell them.

Carl,
You are correct; the dispatcher has no direct control over cab signals. He can, however, indirectly change the cab signal by, as you pointed out, changing the permissions at Control Points, but that will only effect the cab signals if the train is in the track circuit governed by the Control Point signal (usually two signal blocks).

[Mookie]

Boy I can hardly wait to ask the next question! I will need to go for my PHD in railroading to ever understand even a fraction of any of this!

Mook!

PS - BC

Got your e-mail - but lunch prevails! The boss is paying! And our family do have it's priorities!

[CShaveRR]

I'm not sure that a dispatcher has any control over the cab signals, any more than he does over intermediate block signals. If he wants a train to stop at a point other than at a signal which he controls (hence the name "control point"--right, MWH?), he still has to tell them.

[CShaveRR]

SJ--check your e-mail!

BC

[Mookie]

Ok, I got it now!

I think a lot of people out here are novices and will enjoy learning this right along with me!

And the fact that the east is different from the midwest is different from Canada - that just adds to the confusion!

Thank you my friend!

Mookie

[edblysard]

Mookie...
See GCOR rule 5.16 Observe and Call Signals

"Crew members in the engine control compartment must be alert for signals.
As soon as signals become visible or audible, crew members must communicate clearly to each other the name or aspect of signals affecting their train.
They must continue to observe signals and announce any change of aspect until the train passes the signal.

If the signal is not complied with properly, other crew members must remind the engineer and/or conductor of the rule requirement.
If the crew members receive no response or if the engineer is unable to respond, they must immediately take action to ensure safety, using the emergency brake valve to stop the train, if necessary."


We do this because, in some instances, it is quite easy for you to see the "wrong" signal, especially if your at a fairly crowded interlocking with several signals.
It keeps every one in the cab on the same page, and ensures we are all looking at the same signal, and know what we are doing, and where we are going.
It helps us keep each other alert.

Some railroads require their crews to announce over a common radio channel their train ID and the aspect of the signal they are passing.
This allows all other trains on the common channel to know what train is where, going in what direction.
With in-cab signals, it also allows crews to compare the signal in the cab with the wayside signal.
The GCOR says you are to comply with the most restrictive of the two...so if you have a restrictive in the cab, but a green on the signal mast, you slow down and go looking...a simple failsafe system.

Add to it the fact that a control operator(dispatcher) may want to slow down, or stop a train somewhere between signals, in cab signals can allow them to do so.
Most of the in-cab signals I have seen also have a audible tone that sounds when the signal changes, and the signal displayed show the aspect of the last signal passed.

The above applies only to railroads who use the CGOR, in the Northeast and east of the Mississippi they have a different rule book...but I would bet the rules are pretty much the same.

Ed

[dehusman]

New locomotives only have cab signals if the railroad ordered them. The new UP units will have cab signals, a new CSXT unit probably would not.

Calling of signals is a railroad by railroad thing, some railroads require it, some don't.

Dave H.

[Mookie]

With apologies to Sir Chicken and rest of forum - I posted Slow and Easy about cab signals. Then went home for the weekend and completely missed reading the replies until yesterday! Poor MC caught heat for something he didn't do.

Anyway - back to the subject - I read through all the answers and need some clarification. I just would like to know if the newer locomotives, EMD and Dash 9's have cab signal indicators. Let's start there. Do they show that you are running under a "green board" when there are no signals by the tracks.

And combine that with signal calling - if your rules are signal calling, you call signals especially in the more crowded situations (lots of interlockings? is that what several tracks in an area is?) and what about the wide open spaces? Every "yellow or red board" is called either to crew or on radio?

Gotta go with just a couple of sentences, people. I can't digest that much information all at once. And remember, I have only been on 2 engines - both fairly old, don't have a clue what a video of running an engine looks like and don't have access to the inside of a cab here.

Just need patience!

Mookie