Electroliner 1935 I I detect nits being picked.
I I detect nits being picked.
Picking nits is so much fun
As for "electric" vs "elecronic", my B.S. degree from UC Berkeley was for Electrical Engineering and Computer Science, though very few of the EECS majors at Cal did much with either electric power systems or electrical machinery.
To add a bit more fuel to the fire, an EE professor at Stanford, Tom Lee, stated that the field of electrical/electronic engineering got started from a gigantic screw up with the early trans-atlantic telegraph cables. Note there were no active devices (vacuum tubes, transistors, thyristors, etc) at that time. The chief focus of study in that work was the propagation of the signal through the transmission - which is a subject that still catches a lot of EE's unaware.
As for electrically controlled braking, one of Westinghouse's chief motivation for improving the triple valve was that he didn't want to use electrical control of the air brakes.
Electropneumatic braking for passenger cars was available in time for use on the early streamliners (mid to late thirties) and many of those installations had some form of anti-lock braking.
- Erik
Instead of arguing endlessly about :"electric" vs. "electronic" it would make more sense for people to actually find out something about ECP braking.
Here is a link to a good article about ECP braking—and yes, it is an electronically controlled system: http://www.railway-technical.com/brake3.shtml
Kurt Hayek
sandiegoInstead of arguing endlessly about :"electric" vs. "electronic" it would make more sense for people to actually find out something about ECP braking.
But..... But..... But..... Some posters love to argue for the sake of argument alone, never mind accuracy.
Norm
sandiego Instead of arguing endlessly about :"electric" vs. "electronic" it would make more sense for people to actually find out something about ECP braking. Here is a link to a good article about ECP braking—and yes, it is an electronically controlled system: http://www.railway-technical.com/brake3.shtml Kurt Hayek
Thank you. That was the article I read. I should have linked it. Sorry if calling somone out on their preposterous statement ["There is at present no better system for APPLYING the brakes on trains than compressed air. ECP, which has a documented history that goes back before Westinghouse invented the triple valve, simply uses an electrically controlled valve to control the airflow to and from the brake cylinder"] is so irritating to certain posters.
C&NW, CA&E, MILW, CGW and IC fan
schlimmAgain, returning to the point here, to state that electronic brakes were used as far back as the triple valve is an obvious falsehood.
Yes, it is, and I have tried to correct that impression by editing the previous posts.
The point I wanted to establish, and missed, was that electrically-controlled proportional operation of brakes was developed prior to the invention of the triple valve. erikem has, I think, corroborated this. I do not think we need to proceed further with a pissing contest of any kind.
As it turns out, I have been informed that the most likely 'formal' distinction between 'electric' and 'electronic' appears to be a bit different. "Electronics" is the discipline formerly known as "radio engineering", and when the American organizations for radio engineering and electrical engineering merged, the current name (IEEE) was chosen to reflect this.
George O. Smith had an interesting 'take' on the legal definition of information vs. power transfer in one of his "Venus Equilateral" stories ... where he brought up, btw, the functional overlap in the applicable technologies (albeit for somewhat melodramatic plot purposes!)
EuclidI am generally interested in ECP brakes, but the part I currently find most interesting is the fact that they will be put into use in the U.S. That will be only for oil trains, but still, it seems like really big news. That is a MAJOR change in the railroad industry. And yet strangely, I find no news update on the plan or conversion underway since it was announced last spring.
Some of this involves the ongoing objection to 'mandated' ECP in general that we've been commenting on. I suspect that as long as ECP is being resisted in general, the cost of its actual application to HHFT consists will be avoided or at least 'put off a while'.
On the other hand, there are coherent efforts to provide ECP installations on HHFT or other consists, with high assurance and within an appropriate timeframe to meet the mandate if it stands. I know of at least two. Do not expect details on any public forum.
I would like to see ECP adopted for certain traffic; indeed, I'd like to see some system of it adopted for general train handling. But that decision does come with substantial financial 'consequences', and you can readily observe that, for example, any decision by NS or CSX to start spending money on anything more than general feasibility studies would be used by Ackman and Co. or a group like the Children's Fund as a substantial proof of 'waste of shareholder value'. Both in the short run that so many financial 'analysts' ruin their analysis by emphasizing, and in the potential long run if ECP use doesn't become prevalent 'enough' or the technologies they adopt become obsolescent ... as so many technologies in ECP over the years have indeed become.
EuclidIf the 2021 deadline arrives unmet, will the railroads threaten to stop hauling oil by rail because it would be illegal after the deadline? How would Congress and the FRA react to a shutdown of just oil trains? I suspect the answers to these questions will be greatly affected by the perception of oil train safety as operating effects unfold over the next five years.
With the number of oil trains reduced dramatically the past year or so, the task to convert them to ECP isn't anywhere as gargantuan as it once was. So the issue is nowhere near as MAJOR unless oil prices shoot back up.
It's been fun. But it isn't much fun anymore. Signing off for now.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any
Wizlish Euclid I am generally interested in ECP brakes, but the part I currently find most interesting is the fact that they will be put into use in the U.S. That will be only for oil trains, but still, it seems like really big news. That is a MAJOR change in the railroad industry. And yet strangely, I find no news update on the plan or conversion underway since it was announced last spring. On the other hand, there are coherent efforts to provide ECP installations on HHFT or other consists, with high assurance and within an appropriate timeframe to meet the mandate if it stands. I know of at least two. Do not expect details on any public forum. Both in the short run that so many financial 'analysts' ruin their analysis by emphasizing, and in the potential long run if ECP use doesn't become prevalent 'enough' or the technologies they adopt become obsolescent ... as so many technologies in ECP over the years have indeed become.
Euclid I am generally interested in ECP brakes, but the part I currently find most interesting is the fact that they will be put into use in the U.S. That will be only for oil trains, but still, it seems like really big news. That is a MAJOR change in the railroad industry. And yet strangely, I find no news update on the plan or conversion underway since it was announced last spring.
Both in the short run that so many financial 'analysts' ruin their analysis by emphasizing, and in the potential long run if ECP use doesn't become prevalent 'enough' or the technologies they adopt become obsolescent ... as so many technologies in ECP over the years have indeed become.
Why not expect details of the two ECP installations on a public forum? Are you referring to details that you cannot provide due to proprietary reasons? Or are you referrring to something more general?
What are the ECP technologies that have become obsolete over the years, as you mention?
EuclidWhy not expect details of the two ECP installations on a public forum? Are you referring to details that you cannot provide due to proprietary reasons? Or are you referring to something more general?
Mostly the former, although (as you are aware of, in different context) there are patentable elements that must be protected against 'premature disclosure'.
I suspect most of the actual "competitive advantage" in implementation has more characteristics of trade-secret than actual patentable innovation -- but again, there is a reason why 'trade secrets' are kept secret...
Not to pick a nit, but I said 'obsolescent', not 'obsolete', and there is what I consider to be an important difference between those terms.
'Obsolescent' technology is still perfectly workable, and still worth supporting (if you have the interest or, for example, are 'heavily invested' in older technology, like NS was with DC traction motors). It just isn't the 'best' solution in modern terms -- it's becoming outmoded, but isn't 'there' yet. A somewhat remarkable example of this in action was the Republic Locomotive (?) 'starship' FL-9 rebuilds, which were meant to be amazingly state-of-the-possible when built, but had become difficult to maintain, and essentially unsalable to other potential FL-9 users, less than a decade later...
For examples of obsolescence in ECP over the years, start with just about ANY instantiation of actual electronic equipment or devices, and proceed directly to programming environments, test tools, magnetic materials, RF spectrum allocation, etc.
Proceed to look at how the development of consumer electronics, and common standards for industrial systems, have evolved over the years, making OTS technologies using some standards much more cost-effective even when they offer far more effective functionality. One example would be RFID, another the advances in differential GPS. At least some reasons for 'wireline' connection between cars (apart from 220V power) are no longer as 'necessary' as they were when the technology was 'frozen' and marketed.
CMStPnP Are railroads going to eventually replace compressed air with electronics
It's not really the type of investment that offers an attractive ROI, especially when you consider the number of cars out there that would have to be retrofitted to achieve universal deployment. And just consider what such a move would do the the value of all the disused cars sitting out on leased dormant lines. I'd guess that it will primarily be used in specialty applications and/or in dedicated use trains.
My guess is that you will have crewless trains before there will be a universal adoption of ECP.
WizlishGeorge O. Smith had an interesting 'take' on the legal definition of information vs. power transfer in one of his "Venus Equilateral" stories ... where he brought up, btw, the functional overlap in the applicable technologies (albeit for somewhat melodramatic plot purposes!)
When I got my EE degree from Univ. of Cincinnati, my major was in power. But I got into communications and worked with Microwave System and then Fiber Optic System design. So information does not require an electrical medium to transmit information. New disciplines come into being and you see that in your new cell phones. They outdo Dick Tracy and Star Treks communicators. In the 60's transisters couldn't work reliably under the hood of a car, (temperature extremes and rf noise) but those have been overcome. (In less than ten years) Your car today has more computing power than the early astronaughts. The early electical systems on locomotives have been replaced by sophisticated computer controls that do more than was dreamed of back in the1930's and even the 1960's. It's easy to talk about the many issues with ECP but trial and error will find the things that need improvement. While steam locomotives are great to see and ride behind, does any body think the way we used to do things is the best. While the KISS principle still has merit, I think its time to move forward with ECP and see whether the bugs can be found and removed, and determine if the benefits justify the cost.
Wizlishhe point I wanted to establish, and missed, was that electrically-controlled proportional operation of brakes was developed prior to the invention of the triple valve. erikem has, I think, corroborated this.
Getting facts straight is not a 'pissing contest' regardless of some peoples' discomfort. I read Erik's comments. I do not think he corroborated your modified contention. He said, "As for electrically controlled braking, one of Westinghouse's chief motivation for improving the triple valve was that he didn't want to use electrical control of the air brakes." So what electrically controlled air brake system existed at the time of Westinghouse's invention? I would say there was NONE. As in history and most/all other fields, show us the evidence.
Robinson's 1872 ATC used a DC current and detection, essentially a signaling/train occupation detection advance. https://www.princeton.edu/~ota/disk3/1976/7614/761411.PDF Its use was totally unrelated to the modern electronic pneumatic braking, an advance on electro-pneumatic braking (ECP), in the article which was linked by sandiego. Frank Sprague's contributions were reliable electric streetcar overhead current catching devices and MU controls.
schlimm Wizlish he point I wanted to establish, and missed, was that electrically-controlled proportional operation of brakes was developed prior to the invention of the triple valve. erikem has, I think, corroborated this. I read Erik's comments. I do not think he corroborated your modified contention. He said, "As for electrically controlled braking, one of Westinghouse's chief motivation for improving the triple valve was that he didn't want to use electrical control of the air brakes." So what electrically controlled air brake system existed at the time of Westinghouse's invention? I would say there was NONE. As in history and most/all other fields, show us the evidence.
Wizlish he point I wanted to establish, and missed, was that electrically-controlled proportional operation of brakes was developed prior to the invention of the triple valve. erikem has, I think, corroborated this.
I read Erik's comments. I do not think he corroborated your modified contention. He said, "As for electrically controlled braking, one of Westinghouse's chief motivation for improving the triple valve was that he didn't want to use electrical control of the air brakes." So what electrically controlled air brake system existed at the time of Westinghouse's invention? I would say there was NONE. As in history and most/all other fields, show us the evidence.
SD70M-2Dude Interesting, can the ECP-equipped cars be mixed with conventional ones in a train, or are they not interoperable? And even if ECP can be made interoperable with conventional air brakes there will still be a big obstacle to its adoption over here: the Class I's love of the status quo and resistance to change of any kind.
Interesting, can the ECP-equipped cars be mixed with conventional ones in a train, or are they not interoperable?
And even if ECP can be made interoperable with conventional air brakes there will still be a big obstacle to its adoption over here: the Class I's love of the status quo and resistance to change of any kind.
Cars equipped with ECP braking only are not interoperable in normal terms since electrical power from the 250 v DC train bus line is needed to actuate the brake valves. There is an "emulation" mode where the cars can be switched and transferred short distances using the ECP system reacting to brake line pressure with power supplied by batteries on the car.
This is generally enough to move cars to workshops for maintenance.
Some cars are dual fitted with both ECP and conventional triple valves but require to be switched between modes (I believe manually, car by car). One operator in Australia, Centennial Coal have two rakes which are dual fitted.
The first batch of Glencore hoppers arrived with full ECP equipment but were set up to use triple valves so that they could be hauled by conventional locomotives until the new locomotives were available, when the triple valves were removed and they used ECP exclusively.
While it would cost more to fit both ECP and conventional braking, it would meet the requirements of interoperability. Procedures would have to be instituted to ensure that the vehicles were in the correct mode for whichever type of train it is to be included.
The downturn in coal traffic has reached Australia, and in addition, Pacific National has lost a major haulage contract to Freightliner. Apart from involving a change from conventional to ECP trains, it is suggested that Pacific National with withdraw many of its ballasted non ECP DC traction coal locomotives, since they cost more to run than AC units hauling ECP trains.
M636C
Euclid I would think that if Westinghouse announced that he was against electricity and for compressed air, that would indicate that there were a lot of people advocating electricity for train brakes at that time-- for both powering and controlling.
If we see evidence, so much the better. But keep in mind railroad engines did not have generators for lighting passenger cars until well after Westinghouse introduced his triple valve. Pintsch lighting systems were commonly used on many lines into the 20th century, when electric lights replaced them for safety reasons. So it seems highly unlikely that others were advocating electric braking in the 1875-1890 period.
First, I'm not getting into a discussion of the meaning of electric vs electronic.
In the book "The American Railway" (about 1889), H. G. Prout, editor, "Railroad Gazette" writes of the Burlington brake-trials of 1886 & 1887. He says that in 1887 "it was shown that by bringing in electricity to activate the air valves, the application of the brakes could be made practically simultaneous throughout the train." He then adds that Westinghouse made improvements to his system that made his system practical.
The book is here:
https://archive.org/details/americanrailway00clargoog
I loaded it in PDF. Go to page 200 in the book (PDF page 235).
_____________
"A stranger's just a friend you ain't met yet." --- Dave Gardner
PoC,
Another reference is White's The American Railroad Passenger Car pages 555-556. This was after the original triple valve but contemporary with the quick action valve. WABCO introduced the HSC electro-pneumatic brake in 1932 for high speed passenger car service.
Compressed air does have a lot of advantages for powering brakes - the compressed air by itself is a form of stored energy, just needing a pressure vessel of some sort. An additional advantage is that an air leak does not create an environmental problem.
Thank you both for the research. The idea of using electricity to activate braking in some manner did not seem to catch on here, although it did in Great Britain in passenger services.
schlimm Euclid I would think that if Westinghouse announced that he was against electricity and for compressed air, that would indicate that there were a lot of people advocating electricity for train brakes at that time-- for both powering and controlling. If we see evidence, so much the better. But keep in mind railroad engines did not have generators for lighting passenger cars until well after Westinghouse introduced his triple valve. Pintsch lighting systems were commonly used on many lines into the 20th century, when electric lights replaced them for safety reasons. So it seems highly unlikely that others were advocating electric braking in the 1875-1890 period.
During the power brake development era, one method was the so called momentum brake, or buffer brake.
schlimm Thank you both for the research. The idea of using electricity to activate braking in some manner did not seem to catch on here, although it did in Great Britain in passenger services.
erikem schlimm Thank you both for the research. The idea of using electricity to activate braking in some manner did not seem to catch on here, although it did in Great Britain in passenger services. I beg to differ. Electro-pneumatic braking was used on several streamliners from the beginning of the streamline era, though it was not universally applied to US locomotive hauled passenger trains. Anti-lock braking is, AFAIK, almost universal on passenger rail cars. As an example, the Pacific Surfliner cars have a Hall-efffect sensor mounted next to a toothed wheel on the axle ends for providing rotational speed data. - Erik
My favourite answer to people who suggest that the USA didn't use EP braking is:
"What do you think the the third turbogenerator on an SP GS-4 or GS-5 4-8-4 is used for? First one for headlight, Second one for Mars light, third one for electropneumatic braking."
When STEAM trains had EP brakes, the system had well and truly been adopted...
erikemI beg to differ. Electro-pneumatic braking was used on several streamliners from the beginning of the streamline era, though it was not universally applied to US locomotive hauled passenger trains.
I knew that. I think the UP's M-10000 or maybe Pioneer Zephyr? But widely used in GB.
schlimm erikem I beg to differ. Electro-pneumatic braking was used on several streamliners from the beginning of the streamline era, though it was not universally applied to US locomotive hauled passenger trains. I knew that. I think the UP's M-10000 or maybe Pioneer Zephyr? But widely used in GB.
erikem I beg to differ. Electro-pneumatic braking was used on several streamliners from the beginning of the streamline era, though it was not universally applied to US locomotive hauled passenger trains.
I think the use in UK was largely in the very late 1940s and 1950s...
Mainly on the Southern Region of BR where extensive main line electrification occurred.
British Steam locomotives rarely had electric lighting, let alone EP brakes as the GS-4 had in 1941. Of course the UK was at war from 1939, effectively on a war footing from 1937-38 so had less incentive for these developments.
Without looking, I believe in a 1980 (November?) issue of Trains about delivering EMD locomotives, there is a tale involving passenger EP brakes. As I recall it was on the CNW and the engineer was relating about how he was running the streamliner (joint UP/CNW/SP operation) that was EP equipped. It had two indicator lights, one that the EP was working, one that it had failed and a selector lever to change over between the EP and normal air brake operation. Approaching a speed restricted curve they were starting to slow for it when the EP failed. He couldn't change over quick enough and make a regular brake application so they went around the curve faster than they should have.
Jeff
I was given a cab ride in a suburban train by the driver, who was a friend. The subject of EP brakes came up and he said he'd demonstrate the difference between EP and Westinghouse brakes. He isolated the EP system, and showed the difference in braking performance.
In the first station, we overran by a couple of metres but as we approached the second station on a falling grade, the driver said "that's enough, I don't think we'll stop in time without EP.." and turned it back on again.
Many years ago I measured coupler forces in 200 car iron ore trains of 30 000 tons. The tension forces were scary but the compression loads in dips were amazing. I've been a fan of EP and ECP ever since.
Aside from the references so far provided, it might be valuable to remember that an electrically-controlled brake setup in the years before the triple valve would almost certainly have used batteries, not dynamos, for power. (The Page and Daniell cell chemistries being two notable choices, and Edison's nickel-iron structure being a later example of a 'workable' alternative). In that period it was common for signal systems to run entirely on batteries (see the centennial 'book' on safety systems put out by Westinghouse for a discussion), and these would have adequate current and life for the applications where electricity would be perceived as cost-effective (in other words, passenger and mail trains that justified their expenses).
There were reasons why the Page cells that Benjiman Silliman, Jr. thought would be the 'future' of electric locomotive traction turned out NOT to be. erikem will have some interesting comments on the 'by-products' of generation of the necessary high currents from them...
I've never questioned the basic assumption that electrically-operated brakes would fail principally on the issue of cost, and secondarily (for the same general reason as the original straight Westinghouse air brake) on it not 'failing safe' (see the British embracing of the vacuum/Eames brake because it could.) Note that even with the 'automatic' triple, there is a perfectly easy way to assure both proportional operation and full graduated release (although of course with worse latency than an electrically-controlled or electronic system): use a two-pipe system, where the control air is in one line, and the 'power air' in a constantly-charged main as in regular ECP. ISTR that Westinghouse actually favored this system, but the 'cheaper' one-pipe won out in the marketplace.
The Decelakron is of notable interest for being an analog, mechanical solution to the problem of increased wheelslide from high-speed air braking (where it is functionally difficult or impossible to modulate application pressure for high vs. low speed on the cars, and high-performance braking, particularly with disc brakes, is needed for higher speeds in restricted block length). See the discussion of decelostats that ends here:
http://www.atdlines.com/pdf/trucks/pv_68.pdf
It's easier, of course, to implement 'antilock' action if you have a Hall-type speed signal that can modulate an electric magnet valve than if you need a mechanical linkage of some kind to a physical valve with seals or seats. But, as schlimm notes, you need an effective power supply (and not just one that produces increasing voltage with increasing car speed, and that starts only with the car moving at meaningful speed, like a Spicer generator) and in the age of steam this involved batteries or dedicated generators on some kind of trainline.
Correct me if I am wrong, but to my knowledge none of the commuter services that used 'trainlined' electric lighting from a dynamo on the engine or a special car also used any kind of electropneumatic assistance in braking whatsoever. And I'd think offhand that this would be a useful niche for that...
One thing that is probably slowing the adoption of ECP is the widespread use of distributed power on long trains. The slave locomotives can initiate a brake application too, making a 100 car train brake much closer to a 50 car train.
Redore One thing that is probably slowing the adoption of ECP is the widespread use of distributed power on long trains. The slave locomotives can initiate a brake application too, making a 100 car train brake much closer to a 50 car train.
2-way EOT's are in almost universal use on line of road trains. In addition to reporting rear end air pressure and movement to the lead locomotive, the engineer can initiate an emergency brake application from the EOT.
Never too old to have a happy childhood!
BaltACD2-way EOT's are in almost universal use on line of road trains. In addition to reporting rear end air pressure and movement to the lead locomotive, the engineer can initiate an emergency brake application from the EOT.
If they could modify the EOT to assist in a service application that would be helpful.
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