Railroad (and other) Polelines Explained
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- Опубликовано: 4 дек 2024
- Have you ever driven down the road or hiked around the hills and wondered what in the world all those wires and cables hanging on the telephone poles are for? I know I used to and when I went to work for the railroad I found out that most telephone poles have nothing to do with telephones!
In this piece I'll go over the various uses of poles but will focus mainly on what the railroad used them for which during my career was mainly signal circuits and AC power.
So, join me for an explanation and some history of polelines!
Great explanation of how the railroad pole lines worked, including many subcontractors involved.
Hi Mark,
Retired after 35yrs of service from a Railroad in NY. Worked all C&S classifications from helper to Inspector and retired as Signal Supvr. Got dragged back in and currently work for Amtrak as a C&S Manager. I appreciate all your videos and find myself constantly finishing your sentences. I always wanted to explain the signal system and record on you tube as you do, but did not have the balls to follow through. Thank you for what you do and congratz on your recent retirement. I Look forward to your videos.
Sal
Thank you and I'm glad you enjoy them! It's always cool to hear from a RR person who likes them. I try to make them simple but it's harder to explain things than it is to just know them!
Thanks for checking it out!
Interesting and educational, thanks. As an old gummer that has hung around tracks all my life I do appreciate these lessons. A great treasure for me is to find one of the old insulators on the ground somewhere. I’ve collected quite a few over the past 50+ years. You don’t see glass on any poles anymore. The “beehive” type are my favorites. You find them from time to time at some sort of sale. Unfortunately the seller thinks they’re worth a fortune, but as I’m sure you know that millions were made so they’re not worth a ton of money. I still grab any glass insulator that I come across that is sensibly priced.
I just gave a half dozen beehives to a kid I know. I found them going through some stuff in the garage. I am not a collector, and threw hundreds of insulators away. I did, however, make sure many went to those who did want them. Thanks for the compliment and for checking it out!
Thanks for explaining what I saw on the Coast Starlight right of way...
The pole lines from the fifties added character to railroad right of ways .
And having to climb them added character to me!
Thanks for checking it out!
Absolutely! I miss them beyond words. The number of cross arms on poles along the lines in my part of the state (on vacation trips with my my family) kept me entertained and fascinated as I pondered why different companies had the number of wires on different cross arms - but more importantly, the arrangement and design of the insulators would, in my imaginative mind, would form cartoon character expressions - crazy I know, but still real to me this day. I wish someone was.Irving who could explain in more detail which arms were Western Union, the dispatchers line, the agents, lines, etc. But thanks for a GREAT video,
So many thanks for an absolutely Super duper video, This comes closer than any other video I’ve seen on explaining the wayside wires on railroad pole lines of which so many have been destroyed. My favorites were certainly the communication lines and poles (disappeared earliest) which had the most cross arms per pole and most unusual arrangements and designs (forming facial expressions) in my opinion.
Believe it or not, we always called them “Utility” Poles around the Phone Company since the majority of the Poles in the 5-state SWB Midwest Region didn’t carry telephone wires which explains why the landline telephone service was highly reliable. Tree and tree limbs pulling electrical and cable wires down didn’t affect telephone service since the majority of our telephone cables (wires) ran either in buried conduit or manholes underground which limited telephone service outages. Aerial cable ran from a Utility pole to the Customer’s residence with a Drop Wire. Fiber optic cable is both underground and aerial. Thanks Mark. 👍
Great video. One nite on the BN back in the early 80’s my dad (signal maintainer)
had 8 miles of red signals in a role, both tracks due to trees falling through the pole line. He was very happy when they eliminated the pole line.
Trees were a constant struggle with poleline. They'd grow under it and short circuits, break lines and the last 20 years we had no gang support to help us. It sucked!
Thanks for checking it out!
When i was a young kid those were called telegraph lines, because that is just what they were at that time. Messages were sent to stations located along the line at intervals. They were powered by low voltage dc power. After they stopped using telegrahs, people began taking the glass insulators from the poles to keep as collectables.
On the railroad, telegraph lines were generally on the other side of the tracks to keep interference from being an issue.
Open signal lines have been in use since the late 19th century.
Thanks for checking it out!
The western union/SP phone lines had 5 arms on them all the way to Mojave as late as 1983, when the poles were removed as 58 was widened through Sand Canyon.
When do you think the last Morse (telegraph) circuits were retired from your road's pole line? A few of the roads in the Northwest were still Train Dispatching by Morse until almost 1980.
FYI factoid: Most railroads didn't use Morse code after the 1880s but created a shorthand version so orders could be transmitted and transcribed more quickly. I didn't know that until I became a docent at the museum!
I know SP had stopped using telegraph in most places by the 1950s and replaced it with telephones and radios. On my territory, they were still issuing orders from Mojave to Colton in 1980. I was hired for the CTC installation to get rid of it. We still had non-CTC sections between Bakersfield and Mojave into the late 1990s but they were governed by automatic block signals.
Thanks for checking it out!
Nice bit of history, thanks. On occasion I've looked at the "telephone poles" on our street and pondered how it all developed. It makes sense from a safety perspective, telephone & cable TV (the safest cables) in the lowest position, 120/240 VAC power to homes above that, and at the very top distribution wires with their (rather nasty) thousands of volts. All placed in a logical layout. The poles themselves have a variety of inspection badges nailed to them. It seems like they're inspected every ten years or so, with a life expectancy of 50 or so years (here in PA), although I'd guess the life expectancy is related to the environment.
There are poles out in the deserts out west that are well over 100 years old.
Thanks for this great video!
Mark, some railroad pole lines had a shorter crossarm at the to with three wires, sometimes two, presumably for high voltage distribution delivered by the commercial local power company. Would this be 240 or 480 volts?
On the SP in Arizona and New Mexico there were two lines, one on the north and one on the south side. What was the convention? One so de for communication and the other for signal?
Santa Fe had many single pole lines with communications at the top crossarm (?) and one or more crossarms below for the signals (?). The power from commercial service was at one edge of the lower (lowest) crossarm. Also, every so often there would be an "H" set of poles with transformers for voltage reduction (management).
I also remember seeing long bond wires with bonds connected by drilling a hole in the tail just outside the angle bar. I'm going to speculate (like you never do) that this application opened up the rare possibility of a pull-apart or broken rail at the joint unprotected by a circuit failure. Ever have that gremlin jump up to confound the integrity?
We could talk for hours.
Thanks Mark for answering my question about your old open lines. It sounds very similar to the phone cable system that I work on today. We used to have open wire pole runs too. I've heard they were also tough to maintain as well. What blows my mind is how they figured out how to carry multiple calls/signals on a single wire or pair of wires!
It's hard to find details about open wire carrier systems, but the information I've found suggests that at least one implementation used AM modulation---same as an AM radio station uses--but with lower carrier frequencies, probably below 100KHz. So in this case the idea appeared to be a modification of what was already figured out in the radio industry.
@@brianleeper5737 that would be communications stuff. Out of my wheelhouse!
@@MarkClayMcGowan We need a retired AT&T person to reveal the secrets :)
@@brianleeper5737 I'm pretty good friends with the local comm tech. I'll pick his brain about it. He's not retired but, as I said in one of my videos, he's one of the only people I know who can make me feel dumb!
@@MarkClayMcGowan I appreciate it. I found that there are Bell System Practices (BSPs) for the open wire carrier systems, but they are not available on the usual websites to find BSPs, seems that nobody has scanned them in. These would explain the equipment used, how to install and troubleshoot it, etc. I imagine that this was an uncommon BSP even in the era when open wire carrier was still being used, compared to say the BSPs for customer equipment installation and repair (most of which have been scanned and are available online).
I'd love more info on how the signal circuits actually work on the tracks. Seems like iron rails wouldn't be a great conductor for digital signals.. so I'd love to learn how it works!
I'm going to make an educated guess and say it's going to be either a differential signal, or high voltage AC. More than likely it will be a high voltage AC signal due to the high impedances that these very long lengthns of cable will have. Because of this high impedance, the cable will have a greater opposition to current flow. In order to reduce the effects of transmission lines opposition to current flow a higher voltage can be used.
Furthermore, the voltage drop of a DC signal will be far greater when dealing with distances like this then the voltage drop of an AC signal. If a DC output is desired, the AC signal can be modulated in some way so that the other end can de-modulate the imposed data, thus receiving the resulting DC data.
I could be entirely wrong about this by the way. This is simply an educated guess/hypothesis as to what is being used or rather what was being used.
All signal line circuits, whether open line or cable, were 10 to 12 volts DC with current in the .500 ma range. Most signal blocks (the track between signals) were less than two miles long so voltage drop wasn't an issue.
We also carried AC from 120v to 3.7Kv on the lines as well as the code line which was around 200vdc at very low current.
The rails are very good conductors and have welded copper wire conductors at all joints in a circuit. Insulated joints are used to separate circuits. In the old relay logic system track voltages were in the .5 to 1vdc range at .125 to .500ma range depending on circuit length except for control point circuits which are in the 1.5 to 2vdc range.
Today's microprocessor pulse system are in the same voltage and current range but are pulsed at different rates which the system interprets for signal aspects rather than using relays to give that information.
Maybe I'll do a "how it works" video about it.
Thanks for checking it out!
I have tried for years to figure out what each of those wires do. It would seem from my research that you would need a minimum of 4 wires to run signals along with two power wires. I believe in addition to the 6 wires for signals, there is two wires for communication and two wires for CTC. Railroad crossing signals usually require another arm on the pole.
You needed eight wires to operate the signal system. Two wires each for the signal control in each direction and two block indication wires.
The code line (CTC) was separate and used two wires that transposed at every other pole.
AC power was also carried on two wires where necessary. If cable was used instead of open wires, the code line and AC had to be on dedicated cables to eliminate inductance in the signal circuits.
Up until the late 80s, crossings used two wires going to the signals in each direction called "wrap around" circuits. If the old 300 units failed the wraps would take over and the crossing would activate when a train passed the signal, which made for very long warning times! Those were eliminated with modern microprocessor crossing controls.
I hope that makes sense!
@@MarkClayMcGowan Yes that was helpful thank you.
The spacing of poles was uniform. Timetables noted the spacing and counting them while timing with your watch let you calculate train speed. Engineers got called out by the crew for speeding because if there was an incident and speed recorder tapes were pulled everyone on the crew had their job in peril...
You mentioned at 7:33 that the signal communications are now sent down the tracks as coded pulses, rather than on the track side open wire. Do railroad still use a "code line" for CTC and if so how do those signals get to/from the houses at all the control points? Thanks again for the very interesting videos.
The codes are now pushed through the radio system and interfaced inside each control point with the signals system. Here is the link to the video I show it inside a cabin. ruclips.net/video/_2GBqFrzEgY/видео.html
I hope you enjoy it and thanks for checking it out!
Thanks Mark. This is all very interesting to me as I come from a radio and telecom background. In doing a fair amount of Googling over the past month on modern CTC code lines, I’ve found that some roads are using satellite links, 900 MHz data links, cell phone data links as well as conventional 160 MHz two way radio links (same band used for train to dispatcher voice comms). I can understand implementing radio code lines via satellites and 900 or 160 MHz radio, but what road would want to put their CTC operations into the hands of a cell phone provider? Maybe commercial customers get a better grade of service than retail customers from cell sites.
One of the more interesting aspects of radio code lines is that there is a free computer program ATCSmonitor that some railfans use to passively monitor train movements on a display that looks like a dispatcher’s console.
Thanks again for your great videos and explanations of railroad operations and technology.
Late 70’s , early 80’s. those lines was then being discounted in use. Almost all telegraph lines have removed now along the rail lines and 120/240 Power service, now supplies the rail way kiosks cabinets.
Much of our signal poleline on the Fresno and Mojave subs was in use until the last upgrade was cut over in 2016.
Mark: If you take 120 volts and diivide that by the square root of 3, you get 208 volts and divide by square root of 3 again, you get 600 volts and again, you get 2160 volts and so on. Tony Vallot
How far can the railroad run the 120 volts before the voltage drop was too much to use?
@@railspike7057 Over 6AWG Cu wire, at the low current needed for battery chargers, you'd get a mile or 2, out of 120 or 240v.
The BNSF in eastern Colorado used 480v single phase power, and got out several miles each way from a commercial power drop.
Many of the pole lines running along Canadian rail lines seem to be in a state of disrepair. I assume their function has been replaced by newer technology, such as buried cable.
It has. We just got rid of the last of our poleline around 2018. It looked terrible too!
I was surprised at how thick and stiff the railroad wire is. 5/32 inch / 8 gauge / 4 mm. Appears to be special alloy material, not very ductile. It must have been rough work to install and maintain it. I can imagine splicing this stuff up on a pole in a wind storm. Our ancestors were a tougher breed of man than we are : -)
We used #9 iron for signals, #10 copper for AC, and copperclad (iron clad in copper) for codeline. The 10 was easy to work with, 9 not that bad, copperclad was almost unworkable! I had the displeasure of working all of it from poles until UP, thankfully, banned us from climbing around 2000.
@@MarkClayMcGowan Thanks for details. I found the 8 gauge wire on fallen poles along the S.P. Salt Lake Division route while making video for my channel. The poles were probably from the 1930's. I often wondered why the pole lines were left in derelict condition. Thanks to your video I learned something to inform future videos. PS- You could make a video on how the old timers did the skillful wire work I have seen. They must have had special tools to make the splices and tie-offs with that thick wire. What you excel at is the details that many rail fans are interested in. In contrast to the dull run-by shots that most other channels do : -)
That would be interesting, but I no longer have those tools or materials at my disposal and UP has tossed it all since there is no more poleline. All the stuff I shot in this video has been removed.
Copper theft was a big problem for Santa Fe, when they had what was left of their code lines until around 2005, when a contractor came and removed them. I think it was Inchworm Services, that bid the job from BNSF.
Hey Mark, Didn't the Southern Pacific telecom system form the basis for Sprint which was spun off as an independent entity?
That is correct. It stood for Southern Pacific Railroad Internal Network Telecommunications. They sold it off around 1990.
Thanks for checking it out!
@@MarkClayMcGowan 1-800-PIN-DROP
Speaking about wires, at most rail joints where 2 rails meet but are NOT welded, there's a bolted metal plate across the gap and there's also a heavy stranded wire or cable attached to both rails. What are the wires for?
They're called railhead bonds and are used for continuity for circuits that use the tracks as conductors. The bolted ones are called angle bars. They keep the rail together.
@@MarkClayMcGowan So if its for continuity, if someone was to lay a metal pipe across the rails it would cause a red signal in that block?
@@bfurailroad1104 yes sir as well as if the rail breaks.. Thats the concept if the track circuit. Train axles are solid steel with .06 ohm resistance so when we test we use a .06 ohm shunt cord.
@William Anthony Leasure the RRs considered that at one time but it would only work at a crossing where there is a cabin and most cars that get stuck on tracks, oddly enough, aren't near crossings. They're better off calling 911 or, if possible, shunt the tracks with jumper cables.
@@MarkClayMcGowan I remember a few years ago we had some snowy weather and the city had put salt down and the RR crossing started going down and then back up again. I can only guess that the saltwater was shunting the rails.
I would have liked to have had some of the AC porcelain off the signal lines, and those hover braces those signal lines had through there.
I have found and taken several glass insulators from abandoned pole lines .
Thief.
Old story, possibly true. The SP in Sprint was indeed Southern Pacific. When they upgraded all their wireline systems to Microwave, they had enough spare capacity to sell for TELCO type service. I guess that branch moved on to bigger and better (?) communications and became the Sprint we all know and love (?).
A lot of it was actually fiber when Sprint started. I have seen underground utilities marked along miles of a railroad right of way and the Sprint line ran directly under all the signal cases. MCI did not except in some relayed sections the Sprint and MCI went in the same trench.
Sprint stood for Southern Pacific Railroad Internal Networking Telephony.
Ok? I ask about the two pole lines too soon. Asked and answered.
I have e a question.. can I send you an email ?
Of course! Motopoet59@gmail.com
I'm still waiting to hear from you!
Thank you Mark but I already asked it in one of your other videos, it was asking why some signal heads are turned and you already answered it, Thank you 👍🏻🙂
I have some pictures of some different signals that i took and I want to ask you if you can give me some more information on them. I have pictures of them so if I can send them to you so you can let me know.