Lines down on railroad tracks

[supaduparocka]

Hey everyone, how are you all today?

I run with the West York (PA) Fire Department and just the other day we responded to electrical wires down on train tracks. I was just wondering how far the electricity would go down the tracks before it dissipated?

[nmfire]

Probably not very far. The tracks are grounded so it can't really "travel down the tracks" like piece of wire. As for how wide the field of death around the wire will be, depends on the circuit.

[hwoods]

Probably not very far. The tracks are grounded so it can't really "travel down the tracks" like piece of wire. As for how wide the field of death around the wire will be, depends on the circuit.

Almost. On a wet day, grounding on any surface will be pretty quick, and a small area. On a dry day, electricity will travel longer distances.

Now, Here's the Kicker: Some railroads use Concrete crossties. Concrete crossties use a different technology to affix the Rails to the Ties. A rubber pad is inserted between the Rail and the Tie, and a Spring Clip inserted into the Tie is locked against the rail. This type of system can carry electricity for a long distance, since the rubber pads insulate the rail.

[Dave1983]

I dont have an answer, other then Im not going to test it. Electricity is the one part of this job that scares the s**t out of me.

[DFW333]

It can probably go quite a ways. Remember railroads are divided into "Blocks" and a train occupying a block creates a short circuit in the monitoring system. Thats whay makes automated crossing gates go down, and lets the train dispatchers know where each train is. This system requires each rail to have a wire between it and the next rail to carry the small current the system uses. That can probably just as easily carry the larger current from the power lines.

That said there is a limit to how far that electricity will go, that depends on a variety of factors including the current from the lines and the resistance of the track. The current "safe distance" from power lines down in most areas is 2 poles back. Along a railroad track I would just double that distance just to accomodate the fact that steel conducts electricity better than dirt or grass.

Besides, it's not like there's anything to be gained by being close to it anyway. Even if people are injured inside the hotzone you still have to wait for power off to get them.

[CAPPYY]

Never tried it and I dont recommend it but I wonder if throwing a halagan on the track so it also touches the ground would give you the ground you need.

[DFW333]

Never tried it and I dont recommend it but I wonder if throwing a halagan on the track so it also touches the ground would give you the ground you need.

Hmmmm.....I say we try this out. Someone find a probie!!

[CAPPYY]

I wonder how many new proceedures in firefighting were invented due to the all important probie?

[DFW333]

I wonder how many new proceedures in firefighting were invented due to the all important probie?

I can name one:

Turning the hydrant valve back slightly to prevent someone from trying to "turn it on more" or "turn it off in the wrong direction."

[nmfire]

Why waste a perfectly good haligan bar. Where is hot trotter?

[hwoods]

Why waste a perfectly good haligan bar. Where is hot trotter?

Thanks a Lot!!...... I just spilled Coffee all over the keyboard......

[busterfiremedic]

Heres what is important to remember-
Electricity is looking for the easiest route to ground as it can find. Railroad beds on 2-3" rock are not well grounded. The track is not grounded very often because the spikes go to ties and the ties sit in the rock. I would consider the track electrified (and the ground around it) for as far as I could see. I would treat it just I would any metal fence or wire- leave it for the lineman.

[fire0099881]

It can probably go quite a ways. Remember railroads are divided into "Blocks" and a train occupying a block creates a short circuit in the monitoring system. Thats whay makes automated crossing gates go down, and lets the train dispatchers know where each train is. This system requires each rail to have a wire between it and the next rail to carry the small current the system uses. That can probably just as easily carry the larger current from the power lines.

My Asst. Chief work's for an electrical contractor, and they was running lines over railroad tracks one day, and after getting the go ahead from the railroad guy that was there with them, they was stringing them above the tracks and one of the bare wires got down on the tracks and put the gates down, scared the crap out of him since he was in the bucket truck at this time! then the guy told him what happened, and he said that if you ever have a problem on the tracks just take a chain or something and short out the tracks and that will immediately notify the railroad dispatcher that something is not right at that location. Which I thought was very interesting! So if you ever get bored and want to **** people off just go out and throw a chain over some tracks!!!

[ElectricHoser]

I don't get why folks want to test this stuff out as if it was an electric fence or something, it must be the wannabe MythBuster emerging from within.

If you threw a metal tool down to create a ground path, what are you going to accomplish? As already pointed out, rail beds are generally not well-grounded, so laying a halligan from rail to rock won't do much. A chain? Depends how long. Better find a probie to put it down. But again, why?

Let's just pretend the rail is hot and you ground it. Even at "lowly" distribution voltages, the fault is going to make one hell of a bang and may launch chunks of semi-molten metal at moderate speeds in unpredictable directions. Yay! Great, now did the line trip and reclose? Are we where we started? Hmmmm, better find another probie.

Boil it down: So what if you have a potentially energized rail, are lives at risk? No? Don't touch it. Call the power company. Call the train dispatcher. Keep everyone away. Wait until the power company arrives and go from there.

[voyager9]

Boil it down: So what if you have a potentially energized rail, are lives at risk? No? Don't touch it. Call the power company. Call the train dispatcher. Keep everyone away. Wait until the power company arrives and go from there.

Note to self: trust the guy who works for the power company...
One follow-on question: how far down the line do you need to protect? Its easy to keep people out of the immediate area, but if the rail is energized for a distance in either direction it is going to be much harder to limit access.

[ElectricHoser]

I am not at all well-versed in train rail signalling systems, but I do know that sensing equipment detects the "distance", if you will, that it takes to reach from a single rail at a crossing out to the train axle which touches both rails and back to the crossing, and is thus able to determine the location and speed of the train by measuring how quickly that overall distance is diminishing or increasing, and can therefore activate a signal to close a crossing at a predetermined length of time before the train arrives regardless of the speed of the train. This same detection technology also has some impact on the train operator's signals. From this I assume that the rails are not routinely or frequently grounded, but again I really don't know how their systems really work.

But.... I know that in some winters the somewhat conductive salty slush from salted roads after a good snow would complete the "circuit" at a crossing and fool the signal into thinking a train was sitting right in the intersection, causing the crossarms to stay down indefinitely..... we were the ones called out to rinse the crossing area of salt and slush until the signal deactivated!

Anyway.... and I apologize, I know I go on and on too long.....

The voltage potential from an energized rail in the very unlikely event that an energized wire fell on ONLY the rail and did not fault to lockout would go a long, long, long, long way. A LONG way. But knowing that extremely low-voltage (harmless to humans) equipment is attached to the rails, I suspect that even the lowest distribution voltages of a couple thousand volts would fry right through that puny detection stuff and fault to lockout immediately. The real-world possibility of a line falling on a rail and actually keeping that rail energized at high voltage withou finding a path to ground seems so remote as to not worry about preparing for. In any case, if it did happen, you would not be able to protect the miles of rail that would be hot (after all, power lines run hundreds of miles hot, why not a rail?).

So what do you do? Call the power company. Be specific about the problem/ They will make sure the line is de-energized if it hasn't already locked out. Problem solved.

Fun questions.

[nmfire]

Again it is highly recommended that you not wreck a perfectly good tool trying to create a ground. As mentioned before, it would be much better to throw a completely useless tool such as Hot Trotter.

I'm not sure what planet my brain was on when I said the tracks were grounded. Duh.

[Weruj1]

Why waste a perfectly good haligan bar. Where is hot trotter?

OMG ROFLMAO !!!!!!!! I am glad I wasnt drinking anything.

[hwoods]

OMG ROFLMAO !!!!!!!! I am glad I wasnt drinking anything.

I was. (see above) I know, I shouldn't read the forums while drinking coffee......

Electric Hose Man - ( ) The Tracks have areas where a piece of track is "Isolated" from the rest of the grid. Signals are operated within the isolated segment, by Rail Induction Current Signal Components. When a train crosses a "Joint bar" into an isolated segment, it sends a signal to the "Device Controller" announcing it's arrival in that area. The Device Controller takes action, based on that info. (Lowers Road Crossing Gates, Turns on Lights, etc) Modern Signal Systems are all Micro Chip stuff, and they work somewhat differently, but you get the idea. At this time, some Railroads are experimenting with GPS Based Signal Systems, that will eventually cause the demise of Track Based Systems.

[ElectricHoser]

Thank you for that helpful piece of education, I appreciate that very much.

I now know just enough to sound like an expert to the truly clueless!