I'm looking for information about shunting signals and especially if there are any special kind used at humpyards.
Thanks
Lars
Posted by JimBaker (Member # 1637) on :
Lars, No one seems to have responded to your question about Hump yard signals.
Back in the late 1950's and 1960's I spent some time at Los Angeles' Taylor Hump Yard, West Colton Yard and also Roseville's Hump Yard. All of these are on the 'old' Southern Pacific in the state of California. (This if you are out of the California area).
The Hump Yard is controlled by the Hump Yardmaster who sits high atop the Control Tower usually at the crest or top of the hump yard, this is where the cars being classified are pushed (railroad terminology: shoved) over the crest of the hump and allowed to begin rolling to allow the 'pin puller' to physically uncouple the car or group of cars, allowing them to roll on their own down the lead into one of the classification tracks in the 'bowl' of the hump yard.
At the crest tower is a signal displaying at least two colors, Yellow and Red. The hump yardmaster or his assistant runs the show from a switch list generated by the SP's computer. In my day, this was a Teletype printout. The yard master would set the signal to Yellow for proceed to begin the shove over the hump. If an error occurred, or things got backed up, he would set the signal to Red, and the hump locomotive engineer would stop the shove until further clearance was given. After all cars in the string were shoved over the hump, the Hump Locomotive would return to the receiving area of the yard or actually continue down in to the 'bowl' in order to make adjustments to whatever was needed on the varioous 'bowl' tracks.
Jim Baker Whittier, Cailfornia
Posted by LLJ (Member # 1925) on :
Thanks alot Jim. It seams like very few knows about this. Havn't found anything on the web about it. I have just read the two part article in Trains magazine about Yards. Very intresting article.
In U.S., sunting could be taken literally to mean shorting, rather than for switching or marshalling activity. Certain semantics could get you in trouble in this heightened safety era. I'm surprised authorities havn't come after you yet to inquire about intentions of foul play.
Posted by LLJ (Member # 1925) on :
Do You mean that the term shunting is ilegal or what? Pleas explain to a non american citizen.
/Lars
Posted by Andybuzz2u (Member # 2008) on :
Ok in most hump yards there is no signal to shunt..most are controlled by packset(radio)verbal instructions to the crew working the hump as the hump yardmaster classifies the cars going over the hump by destinations that the rail line services..as with the the former SP hump in Houston,TX this is done buy a lighted bill board that tells the pin puller how many cars to let go so next to no other signals or given except to have the engineer start backing up or to stop if problems accur such as pin refuses to lift or if barkes are sit on a car hand or air. To "shunt" a signal is to short a circuit that does one of two things. The next governing signal will display a red or stop indication as that route ahead is an occupied block or there is a broken rail or other mechnical defect and the dispatcher gives verbal authority to the train to pass a absoulute stop indication and be on the look out for train other defect and the train will proceed prepared to stop with in one half the range of vision and not exceeding 20mph..the other is to shunt crossing signals...the automatic crossing devices work off of this to that is how they know when a train is near and provide warning to the motoring public. I am more worried about the stuff kids put on the track from the sourrounding neghiborhoods than i am a terrorist attack on my train...Andy.
Posted by LLJ (Member # 1925) on :
Thanks alot for the info andy. The term shunting in the meaning switching I belive comes from UK, I picket it up someware, and thought it was the correct term in all english speaking countries. How wrong I was.
/Lars
Posted by Andybuzz2u (Member # 2008) on :
Ok you confused me as far as shunting and signal...but on what you said i think you mean shunting cars...which is indeed switching but is a term that went the way of the fireman as not to many people say that on U.S. railroads anymore and in fact is still used on U.K. railroads today...another correct term used over here is blocking cars that means to put groups of cars in order according to there sit out points along the route..hope this helps you any.....Andy
Posted by barrydraper (Member # 737) on :
"Shunting" in US Railroad signaling would mean placing a wire across the rails to drop the signals to red, but your British derived meaning was clear in your original post. Shunting is the correct British term for what we call switching. I don't know of any current yard switching signals, but I do know that before radios became common the Santa Fe, in at least Bakersfield, CA and Los Angeles, CA (Hobart Yard) had switching signals. They were two search light signals on a single mast, facing both directions. There were a series of these signals spaced about every 300 feet so the engineer of a switcher could always see at least one signal. They were manually controled and all signals displayed the same aspect, either red, yellow or green. Red = stop the move, yellow = shove into the yard, green = pull out of the yard. These signals fell into disuse as portable radios were assigned to yard crews, and were removed in the 1980s. I don't know if other yards or other railroads used similar signals.
Posted by LLJ (Member # 1925) on :
Thanks barrydrapper, it was just that kind of information I was looking for. I'm making a humpyard in the trainsimulator program Trainz and as I can't install cab signals, I have to use another prototypical solution.