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  • Telegraph lines and poles

  • General discussion about railroad operations, related facilities, maps, and other resources.
General discussion about railroad operations, related facilities, maps, and other resources.

Moderator: Robert Paniagua

 #677657  by trainsinmaine
 
This may be a dumb question, but I honestly don't know the answer: Back in the days of railroad telegraphy, did the number of insulators and wires on telegraph poles directly correspond to the number of telegraph stations (depots) on that particular rail line? I was raised near the Fitchburg main of the B&M. From Gardner, Mass., east to Boston, there were (in the 1950s) four-tiered telegraph poles with, if I recall correctly, six to eight insulators on each crossarm. From Gardner to Greenfield, the number of tiers decreased to three; from Greenfield to Hoosick, N.Y., two; and from there, three-tiered poles to Union Station in Troy and two-tiered poles to Rotterdam. The B&M branch lines in our area had poles with as few as one crossarm with four insulators each, sometimes not even that. The scheme makes sense to me, but I'm not sure I've come up with the right reason as to why it existed. Can someone fill me in?
 #677881  by dummy
 
sounds logical to me but i dont know either.
 #678234  by Ken W2KB
 
trainsinmaine wrote:This may be a dumb question, but I honestly don't know the answer: Back in the days of railroad telegraphy, did the number of insulators and wires on telegraph poles directly correspond to the number of telegraph stations (depots) on that particular rail line? I was raised near the Fitchburg main of the B&M. From Gardner, Mass., east to Boston, there were (in the 1950s) four-tiered telegraph poles with, if I recall correctly, six to eight insulators on each crossarm. From Gardner to Greenfield, the number of tiers decreased to three; from Greenfield to Hoosick, N.Y., two; and from there, three-tiered poles to Union Station in Troy and two-tiered poles to Rotterdam. The B&M branch lines in our area had poles with as few as one crossarm with four insulators each, sometimes not even that. The scheme makes sense to me, but I'm not sure I've come up with the right reason as to why it existed. Can someone fill me in?
The busier the telegraph or later telephone traffic, the more circuits that would be needed. So if there were fewer trains or other business further distant along a line, there fewer circuits would suffice.
 #716287  by Engineer Spike
 
In later times some of the lines were converted to telephone lines. Others were signal circuits. There was a detailed article about Boston and Maine's communication systems, dating from telegraph, right up to computer systems. This was in the B&M Historical Society's Bulletin within the last 5 years. Now these lines are being replaced. Most of the pole lines are being replaced. Some signal code comes in the rail. Since the railroads have leased their ROW for telephone trunk lines, they sometimes have a clause in the agreement to be able to use some of the space in the lines for their own use.
 #716298  by dummy
 
are glass insulators still being made? or are they using plastic now?
 #717232  by FarmallBob
 
trainsinmaine wrote:Back in the days of railroad telegraphy, did the number of insulators and wires on telegraph poles directly correspond to the number of telegraph stations (depots) on that particular rail line?
I recall the question about lineside wires being asked during an elementary school field trip to the local B&O station in mid-1950’s. (A classmate’s father happened to be the agent/operator there....). As I recall it was explained to us like this:

A railroad’s phone or telegraph system is essentially a “party line”. A single pair of wires provides service to every station along the branch or section.

Another pair of wires brings public utility electric (120 VAC I presume) from the nearest highway crossing to the battery chargers in wayside signals, grade crossing signals, powered switches, etc. (Incidentally us kids were admonished to stay away from the wires on account of the electrocution hazard presented by the power circuit!)

The remainder of the wires are dedicated to wayside signals, etc. I presume by this it also includes remote switch operation, automatic train stop control, probably a 2nd phone line or utility power supply, possibly a few unused spares, etc.

----

Obviously the more control functions a particular line had the more lineside wires were necessary, thus accounting for this observation:

On the single-tracked B&O my class visited the poles had 3 crossarms and carried about 20 wires altogether. (The line was ABS signaled at the time).

The PRR branch at the other end of the village - a very sparsely used, unsignalled branchline - had lineside poles with single crossarms supporting a meager 4 wires. I surmise now these were simple phone and/or telegraph circuits.

OTOH on the nearby 4-track NYC main (heavily used and fully-signaled) the poles carried 5 - 6 crossarms with a dozen or so wires on each – probably 70 wires altogether. Had to have been a nightmare for signalmen in wind and ice storms…

----
dummy wrote:are glass insulators still being made? or are they using plastic now?
I doubt it. Lineside wires are rapidly disappearing, replaced by buried cables or fiber optics. Ie. the pin-type glass insulator in railroad service is going the way of the steam locomotive.

Also when the Conrail Westshore branch lineside poles and wiring were replaced in the late 80's the new insulators were of a tough, engineering grade clear plastic - lexan perhaps? Now 20 years later scattered amongst the the clear plastics are newer, black "pony" sized insulators. These are made of a rubber compound that looks/feels very much like tire rubber. I expect these are about as bullet-proof as an insulator can get.

...FB
 #717821  by David Benton
 
i think the voltage in a ringing signal is around 70 volts or so , so it can indeed give you a tingle . Not enough amps in the phone lines to bury you though . but the battery charging ciruits would probably be a different story .
Still , not discounting the advice to stay away from any wires is always good .
 #718092  by Ken W2KB
 
David Benton wrote:i think the voltage in a ringing signal is around 70 volts or so , so it can indeed give you a tingle . Not enough amps in the phone lines to bury you though . but the battery charging ciruits would probably be a different story .
Still , not discounting the advice to stay away from any wires is always good .
Absolutely. People have been severely injured or killed when they contacted a telephone wire because several spans down a medium voltage (13kV +-) power wire had fallen on the phone wire thereby energizing the phone wire at the 13kV (or 4kV, or 69kV, etc.)
 #766363  by FarmallBob
 
While searching for something else in a 1982 Conrail track chart I stumbled over this key to wayside pole line circuits:
CR pole line diagram 1982.jpg
A few of the circuit names are self-evident (power, spare, etc). "PBX "is likely the phone circuit. Suspect "block", "distant" and "indication" are associated with automatic signal control; "crossing" for grade crossing signals. Similarly "code" may be a coded circuit to command remote operation of interlockings (powered switches and signals).

The rest I can only guess at.

...FB
 #766388  by Arrestmespi
 
They still make plastic insulators have to there is alot of open line wire still out there

As far as the Pole Line
Dispatcher is for the Two way intercom or squawk box to the dispatcher
Radio is for the dispatcher radio circuit
Block is signal circuit for the block you are in ABS
PBX is for the company telephone, each block or several blocks shared an extension from the PBX to make calls also could get you a bell line sometimes
Indication is for signal aspect
Code is delivery or the signal logic to remote locations to be decoded at control points
YD is for Yard limit rules
Distant is the distant track circuit
Crossing is for running the shunt for crossings
Message is ??? never ran into this on the B&O or Conrail systems
Carrier is ??? never ran into this either
Power duh
Spare duh