I was watching a video on U-tube on a train out of Klamath Falls, Oregon. The train was about one mile long. It had pulled into a siding to allow another train to pass. How did the engineer know when his last car was off the main line to allow the other train to pass safely?
you know the length of the train and the length of the siding. And someone has to move the switch back into the mainline position so the conductor will tell them when they clear the switch when they move it back
In theory (and the greatest share of the time in practice), the crew knows how long their train is, as well as how long the siding is.
On signalled/control track, the dispatcher may see an indication that the train is clear of the main. Others will have to discuss that.
Everyone always talks about the rear end device, but the just as important head end device is overlooked in chats like this. The HTD is a portable box mounted on the eng control stand. It is 'linked" to the ETD and displays brake pipe pressure and will also indicate when the rear car on the train stops and begins to move. The device contains a counter which the engr can hit say when entering a siding and will let the crew know when the rear car is clear. Condrs are also required to know the length of their train at all times. Train length is shown on the work order sheets and is adjusted as cars are pick up/set out enroute.
Since it can calculate distance from head to front end and length of train, is it equipped to calculate speed of train in mph?
Al, as far as I know it’s a simple counter, similar to the trip odometer in your car. The engineer starts the counter just past the fouling point and when it hits the train’s footage, then they know the tail end is clear.
WSKid, what you’re saying works with a short train and I’ve done it myself, stop the train, line the switch and walk back to the head end but for a long train it’s impractical, the conductor would have to walk all the way back to the head end, possibly delaying the train. On long trains in OCS(Occupancy Control System, the Canadian version of Track warrant system) we get permission from the RTC to leave the switch lined for the siding so the conductor doesn’t have to walk all the way back up to the head end. The opposing train would get a warning on their OCS Clearance that the switch(es) are lined against them and prepare to stop and line the switch back to normal. In CTC the RTC lines the switch back as soon as the tail end clears the block.
Mary, the counter is in the upper left corner (from Al Krug’s site)
In signaled territory, it’s easy. When the train is in the clear, the interlocking will show clear on the DS’s model board.
In dark territory, it’s a little trickier. Generally, under FRA Emergency Order 24 someone must physically verify the marker and/or last car number is in the clear AND the switch lined away from the train to report clear and give up your authority.
Nick
They are equipped to be accelerometers. This shows the rate of increase or decrease of train speed. The same display that shows the counter is used for the accelerometer display.
Jeff
On a train I was filming a few days ago, as the EOT passed there was a noticable high pitched whining. Was it the EOT or did is just happpen to be the trailing wheels on the last car (autorack) were making the sound? If you want to hear for yourself, the video is here:
http://www.youtube.com/watch?v=R4JV4qU83X0
You can clearly hear the sound from 2:50 to 3:00. Very strange sound that I haven’t heard before while filming. Jamie
Jamie,
I’ve heard a similar sound on rail that has been recently reshaped by a rail grider.
The high pitched sound you heard was most likely a air turbine ETD. These are the 2nd generation devices and are more of a pain in the neck to work w/compared to the battery powered FRED’S.
There are some ‘air powered’ EOT’s out there. In addition to the normal battery, these EOT’s have a small air powered generator to keep the battery charged and to power the electronics. The air power is supplied by the trains braking train line. To spin the generator there must be some loss of air from the trainline to the atmosphere which is the whine that is heard. The ‘leakage’ caused by this type of EOT is well within the allowable trainline leakage rate the is spelled out in the Power Brake Law.
Thanks for the info…had no idea such a thing existed. Jamie
That is the biggest waste of time and lame excuse for not walking your train, if you clear up the opposing train will get clear signals and shoot rightby you and then you leave its faster instead of waiting for him to pull up and stop . when we take siding the conductor always walks up, by the time he shows up the other train may be close, now if the opposing train is only 10 min or so away we will leave the switch open . and the counters you talk about are only a guess and in most cases are not accurate. if the speedometer is off so is the counter, and can be off as much as 500 feet,
What you said is a waste of time. In the OCS system in Canada (dark territory) all trains will get protect against’s on their clearance that say what switches will be lined against them.
When trains are up to and longer than 2 miles, its just absurd to have the conductor wait and line the switch back behind the train.
When railroads got rid of cabooses they had to come up with something to solve the switch problem. That’s what they came up with. Train A would be told to take the siding and leave the switch behind them and train B would have a warning that they would have to stop and line train A’s switch back. MUCH MUCH MUCH MUCH faster and more efficient than a conductor walking his 2 mile long train and holding up the show for 2 hours.
That’s what the counters are they for as well. There is no one 2 miles back to tell you where your tail end is so you have counters. It’s the engineers responsibility to calibrate the counter and time the speedomter.
The counters can be your best friend.
I guess that makes me a lazy conductor who doesn’t want to be pulled in for delay to assignment. We do walk our trains waiting for a meet, but if I’m still 50 cars back when the other train goes by, I’m being pulled in for a statement for delay to assignment.
If I did that at every meet, I’d be hauled in for delay to assignment. Not every railroad does things your way.
That’s why the crew is responsible to test the counter(both the counter on the IDU(head end device) and the counter on the spedometer(if so equipped)) by use of the test mile signs on departure and judge ourselves accordingly.
Just because we do things differently at CN does not make it wrong, nor does it give you the right to give me a hard time about it. I follow our rulebook and have passed every efficiency test with flying colours.
That’s why you always give yourself a couple extra hundred feet on the counter. Either test it against the test mile, or test it by the detectors. We have certain situattions where we are required to make sure a swtich we use is left “lined and locked normal”. Not normaling up the switch can lead to some unpaid vacation. But if there’s a train following closely… you can hop a ride with them to your front end. Sure you are delayed in block, but you are only running restricted for part of a block vs. the whole thing.
Who’s responsible to calculate the distance of the train?
We send the conductor trainee out with a tape measure…