LOCOMOTIVE ODOMETERS

[louisnash]

I know what the mileposts are for. My question is about the odometers. When a train leaves a yard does the odometer get set at "0". I was told by an engineer I know that he saw me taking pictures at MP42.8. I know that the last engine I was in was all digital therefore making the odometer the same. When you engineers are on the road does your odometer tell you exactly the mileage by tenths? I knew also that at crossings the little marker with the 1-800 number has tenths, so I kinda figured the locomotives were equipped as well. I didn't know if there was a point in leaving the yard that the odomter was set.

Thanks for any replies!
Brian (KY)

[edblysard]

The new locomotives, with CRT monitors, have a trip meter, and a distance travled and train length function. If they are so inclined, an engineer will type in the length of his train, from the conductors wheel report or train sheet. If he has to take a siding he will hit the reset to zero when his locomotive is in the clear, and watch the monitor, to see when he has travled far enough to be sure his rear car is also in the clear. Some of the newer locomotives have a gps system, and most have trip meters, just like in you car. Remember, most road crews get paid on a mileage basis, along with some really weird and complicated railroad math, so they most likley would set the trip meter to zero at the yard limit sign when they depart the yard.
On older locomotives, with analog guages, you would use your timetable to determine how far you travled.
Stay Frosty,
Ed

[Jackflash]

In addition to what Ed said most of the time
positions between mile posts are a good guess, or
like Ed said you can use the distance counter and
measure the feet from a mile post to get the
"dot" 1,2,3 ect. also Ed, even on the "old" and
some new locos there is a aftermarket add on
head end device that has a built in counter, just
make sure the wheel diameter is correct for the
loco you're on and you're good to go, jackflash

[edblysard]

All the older ones we get to use down here have the cheap seats, and the pace speedo only. Thats why we like it a lot when UP or BNSF leaves its power on the grain and coke trains, we get to play with the goodies. I did notice on the last UP SD70 we used, the distance counter flashed the wheel diameter just before it reset to zero. Do they all do that, and is that the last number it had programed into it when the wheels were new? I would guess when the shop forces true up the old wheels, they have to reset the counter.
Thanks for the aftermarket info, now all I gotta do is find one. See, you can learn something new every day, if you want too!
Stay Frosty,
Ed

[Anonymous]

Jackflash,
In your response to Locomotive Odometers you stated make sure the wheel diameter is correct for the loco you are on. Could you explain that a litte more in detail? That's a new one for me. How big of a deal is it if wheel diameter is off and the impact? Thanks.

Larry

[Jackflash]

Larry, these "boxes" have a little window in
the back that allow you to change the wheel
diameter that the counter is using to get an
accurate measurement (I think its adjustable
from the high 30 inch to 45 inch in 10ths of
inch) if the loco has 40 inch wheels and the
box is set for 40.5 inch the read out will be
wrong, what I have done is check it between
mile post if its real close leave it alone
if its far off reach around back and adjust
the 10ths thumbwheel switch and check it again
I'm sure that the computer based counter is
adjustable too, but not by the engineer
at least I dont know how, the reason that these
removable boxes are adjustable the way that they
are is they can be moved from engine to engine
with different wheel diameters, Larry I hope that
this helps out. jackflash

[Jackflash]

Ed, dont think I remember seeing the diameter
flash, might have happened, I just dont remember,
I know you can pu***wo buttons down at the same
time and the wheel diameter (thats set in the box)
will display, these are PULSE ELECTRONICS boxes,
when you do see one look in the back, there is
a little window, you will see some thumbwheel
switches inside, by adjusting these switches
you can change the wheel diameter that the box
is "looking for", saw something new not to long
ago, one of these boxes had the ability to tell
you where in your train a dynamiter was, (if you
had one) you had to know your train length, and
enter that length into the box, and the box would
come back and tell you how many feet back the
UDE was, didnt need to use it, and only seen this
feature that one time, jackflash

[edblysard]

Hi Larry,
What will happen is, if the counter is set to a 40" diameter, but the wheel has worn down to say, 39.5", the distance the meter displays will be wrong. The meter counts the number of revolutions the wheel makes, when you dial in the diameter, the meter add the distance the wheel should have rolled. If you know the cross section diameter, or the height of the wheel, you can figure out the outside diameter of it, and how much distance it would cover if you rolled it in a straight line. Then count the times the wheel revolved, and you have the distance moved. Any variance from the true wheel diameter would introduce a error, which would add or subtrack distance depending on which way your made your error, to big or to small. It would be cumulative, and add up real fast if it was a large error, say the 1/2 inch mentioned.
Add in a half inch for every wheel reveloution, and you can see on any run over a few miles the error would become quite large.
Dont know the math for figuring out the OD of a circle,(wheel) cross diameter times pi divided by some other equals something, but it works.
The impact is if there is a error, and you use your meter to tell you that you have travled far enough to get the rear of your train in the clear in a siding, but the meter was set for a larger wheel, you may leave the rear end hanging out, and you stop, the whole time thinking your in the clear but your not.
Going to dig out the kids algebra books to find out the math.
Stay Frosty,
Ed

[Mookie]

ok - I am still lost, but get the "jist" of what you are saying. Now...in the "olden" days when they had a caboose and a conductor on it, wasn't he the "meter" to tell you if the rear end was clear - either by radio or by lantern? Is this meter relatively new?

Jen

[Anonymous]

Jackflash/Ed
Thanks for the info.
Larry

[BRAKIE]

Jenny,When I worked on the PRR and later the PC after the great merger) and later the C&O it was indeed our job to tell the head end that the cabin was in the clear..This was done by train phone then on the PC by radio..On the C&O/Chessie we would radio the end head end and tell them we was in the clear.

BTW If the switches was manual and we was running under form 19s then the head brakeman would swing off the engine and run to the switch,unlock and throw the switch to line us into the siding and the rear brakeman would close and lock the switch after the cabin cleared..Then would run to catch the cabin car and swing aboard...Of course this was done at slow speed.

[Mookie]

Larry - form 19?

Thanx

Jen

[wabash1]

The speedometer and the counter (distance counter) are both on the same wheel. what the distance counter reads is off the speedometer. if i dont get a measurement from someone watching my train i can tell what the differace will be when checking the speed accuracey. for every 1 mph fast reading is 200feet on the counter in otherwords if i have the speedometer on 50mph and the measure mile shows me doing 48mph then the train is clear 400feet more than it shows. these are observations i have learned. its not a science.

[Jackflash]

And J, I do similar things, if I know the length
of my train with a wrong counter reading, its
still going to be that (wrong) length 20 miles
down the road so I have accuracy, and the train
is all on main track, even though the counter says
the tail end is still in the hole. jackflash

[BRAKIE]

Jenny A Form 19 was like a track warrant/permit is today..It give you special instructions and permission to operate on a given track..It would look somethuing like this if memory serves me right. Like this:

Form 19 Date: 6/12/67

To C&E Extra 8818 eng 8818
At High(high Street tower-Columbus Oh)

Operate #2 main between mile posts 122.0 to mile post 123.3 account track maintenance -watch for track gang at mile post 122.9 use bell & whistle..Do not exceed ten(10) mph at MP122.9
Cross over #1 main at MP123.3
JA Harrison.
operator.HS

I made the mile posts up since I have long forgotten the real mile posts numbers..Same for the name of JA Harrison..

[Mookie]

Larry: Thank you! I read it and it made sense!
Kind of like peeking over someone's shoulder!

Jen

[adrianspeeder]

Hello Ed,
I think what you are looking for on the formula for circumference is 2 x pi x the radius, or 2piR. Pi times the diameter also works.
I also have a question for you. I enjoy playing Microsoft Train Simulator, and really like doing yard switching and I would like to know so i do it right. When a cut of cars is parked, how many handbreaks are put on, and how fast do you go when coupling? thanks
-Adrian

[edblysard]

Hi Adrian,
Max coupling speed is 4 mph or less against a standing cut of cars using a locomotive. If you are kicking cars, well, lets just say you get them going fast enough to get the job done.
Railroad terminology lesson. You park your automobile, you tie a cut of cars down, and tie enough hand brakes to prevent movement, there is no forumla for that it's a judgement call, you have to learn what works and what dosnt. If in doubt, it better to have too many, than not enought. After you have done enough flat yard switching, you can judge how hard to kick them to make them go only as far as you need them to. I routinly let cuts of 15 loaded cars go at a time, against a pair of "bumper" cars, each with its hand brake tied. But I have been doing this for almost 7 years on the same lead, I know where the cars are going to slow down, how the rise of the track acts like a brake, if I and kicking or switching heavies or lights, stuff like that, so I can "float" them down to the bumper cars.
A rule of thumb we use on the PTRA is one hand brake for every ten cars on any incline, small or large, and one brake for every 20 on flat level track.
I dont play microsoft simulator, but I would suggest starting out with the one brake per 10 car system, and work down from there to see what the minimun you can get away with.
Hope this helps,
Stay Frosty,
Ed

[Anonymous]

In response to the trueing up of the wheels. I'm a service technician on a fleet of Dash 9 G.E loco's in Australia and the wheels are re-profiled when damaged or worn to prvent uneven diametres of the wheels which can cause the locomotive to suffer from wheelslip. A wheelslip problem can cause the train to slow and in turn take longer to reach the final destination on time. On the Dash 9 G.E locomotive you have the ability recalibrate the wheel size through the D.I.D panel in the drivers cab. Cheers from B.T

[Jackflash]

Hey J you reading this,,in a post somewhere else
you asked what a driver was (in relation to operating a train) well here it is again, now I'm
like you, you drive a car or truck, you dont (cant) drive a train, I drive to and from work
but I dont drive at work, do pilots drive airplanes ? can you drive a bulldozier?
why are engineers called drivers in some places ?
jackflash

[edblysard]

Thanks for the info, out shop trues up the wheels on our switchers because the lead jobs motors are run facing in the same direction all the time, on a curve, and the outside wheels wear down quicker than the inside ones.
Hows th AARC coming alon?
Stay Frosty,
Ed

[wabash1]

yes everytime someone tells me i drive a train i haft to pull that one. and ask them to show me how to drive it. we have conductors and brakemen who do the same thing. and do it over the radio really showing their ignorance. of course they are new hires.