Western Railroad Discussion > Will never understand The Overland signals

Back in the olden days one could look at a block signal along a track and pretty much decipher what was going on traffic-wise in the local area.  

Pretty basic (although sophisticated for it's time) operation. 

Not so much the signals in places like the UPRR Overland in Nevada. These things have a mind of their own.  

Doesn't matter how remote the location or if there are no trains for a hundred miles these signals will suddenly light up with sometimes quite the variation.  

Flashing red going to yellow for a bit then out. Then going steady red to a green.  Never seems to be the same pattern. 

Probably self-testing but one might think the self-test would display the same pattern each time?

It's always interesting on a real dark night on a lonely stretch of track when a signal suddenly comes on green. And it's the only one for miles doing so.  All others are dark. 

Again not like the olden days. 

Chuck 

Generally the control point signals will light up when the dispatcher sends a command to them. So when the dispatcher lines up a route for a train from Control Point A to CP E, all the CP's between the two points will also light up (CP B, CP C, CP D). The last CP will also light up but will be showing a stop signal. Intermediate signals may or may not light up until a train is in the block, but that just depends on how they are wired. If they do not light up until the train is in the block, the signal is "approach lit".

Ted Curphey
Ontario, OR

if an approach lit ABS signal is passed, it should light up red - what will the opposite direction signal show?

Seems out here in the UPRR Great Basin the color "lunar" isn't used anymore?

Used to see lunar a lot and now only on rare occasions these days some random signal out on the Nevada Sub will go full lunar or a flashing lunar although hard to tell exact color from long distances.  

Can these modern LED signals still flash lunar? 

Maybe AI has taken over and the signals are planning some caper.  They do some random things. 

Chuck 

 

Red

dragoon Wrote:
-------------------------------------------------------
> if an approach lit ABS signal is passed, it should
> light up red - what will the opposite direction
> signal show?

Or if the maintainer leaves the lamp test nut screwed down, the signals will remain lit and change to whatever flavor the route is lined up to.

funnelfan Wrote:
-------------------------------------------------------
> Generally the control point signals will light up
> when the dispatcher sends a command to them. So
> when the dispatcher lines up a route for a train
> from Control Point A to CP E, all the CP's between
> the two points will also light up (CP B, CP C, CP
> D). The last CP will also light up but will be
> showing a stop signal. Intermediate signals may or
> may not light up until a train is in the block,
> but that just depends on how they are wired. If
> they do not light up until the train is in the
> block, the signal is "approach lit".

RailDawg Wrote:
-------------------------------------------------------
> Seems out here in the UPRR Great Basin the color
> "lunar" isn't used anymore?
>
> Used to see lunar a lot and now only on rare
> occasions these days some random signal out on the
> Nevada Sub will go full lunar or a flashing lunar
> although hard to tell exact color from long
> distances.  
>
> Can these modern LED signals still flash lunar? 
>
> Maybe AI has taken over and the signals are
> planning some caper.  They do some random
> things. 
>
> Chuck 
>
>  

A flashing lunar isn't used on the UP.

I haven't verified it, but the PTC compatible signals probably have replaced the lunar signal with a flashing red signal to indicate restricting track. Lunar can be confused with background lights, but the flashing red has a higher rate of flash than FREDs or aerial warning lights (cell towers, ect.), so it's not easily confused for other lights.

Ted Curphey
Ontario, OR

An Aboslute signal when coded up from Stop, may go through each capable indication until it reaches the best signal it can display based on Block condtitions. This cycling I think is that while it is actively acting on the codes sent, the blocks ahead take a few seconds to get a read on...so the signal is getting a better indication on each block it reads...most will clue you in on the next two blocks....Approach and Restricting only give you the one block ahead of course. 

After being dark signals never seem to go straight to a green light. 

There's always a flashing amber for about a minute before a high-ball is given?

After a train has passed sometimes the signals go from red to amber to dark and sometimes red to flashing amber then dark.  

It's strange when just one signal suddenly lights up with no trains for a hundred miles.  

Dumb question but as the UP replaces the older signals with the newer LED signals is there also an upgrade in signaling electronics in the trackside boxes?

Chuck

RailDawg Wrote:
-------------------------------------------------------
> After being dark signals never seem to go straight
> to a green light. 
>
> There's always a flashing amber for about a minute
> before a high-ball is given?
>
> After a train has passed sometimes the signals go
> from red to amber to dark and sometimes red to
> flashing amber then dark.  
>
> It's strange when just one signal suddenly lights
> up with no trains for a hundred miles.  
>
> Dumb question but as the UP replaces the older
> signals with the newer LED signals is there also
> an upgrade in signaling electronics in the
> trackside boxes?
>
> Chuck

If a signal lights up randomly with no traffic no where....something has shunted the circuit somewhere in the next couple blocks....could be anything....