Leo_Amescould EMD's preference for changing the electrical system have been driven primarily by the desire to open them up to their full horsepower potential instead of having to derate them?
My uncharitable feeling -- not knowing anything practical about it, mind you -- used to be either that management thought 'a generator was a generator' or that the savings from reusing "most' of the electrical gear was greater than the need for full 'rated' horsepower in service. That is probably unfair to the EJ&E people involved in the rebuilding decisions.
Shadow the Cats owner Just look no further than the EJ&E and their center cab Baldwin engines. When they were sent to EMD to be reengined with new diesel engines EMD wanted to change the electrical systems including the traction motors. The railroad said touch that and we would see you in court. What one of those centercabs could drag took 2 sd38s to do
Just look no further than the EJ&E and their center cab Baldwin engines. When they were sent to EMD to be reengined with new diesel engines EMD wanted to change the electrical systems including the traction motors. The railroad said touch that and we would see you in court. What one of those centercabs could drag took 2 sd38s to do
Instead of improving compatibility for EMD's diesels, could EMD's preference for changing the electrical system have been driven primarily by the desire to open them up to their full horsepower potential instead of having to derate them?
These rebuilds (And the later rebuilds by Baldwin themselves) were limited to only 2,000 horsepower due to limitations with the original electrical system, even though the paired replacement diesels from both builders could've put out a combined 2,400 hp.
Series to parallel transition has to do with motor speed (more particularly controlling back EMF) and not with low-speed performance.
What made most of the difference was the much greater amount of copper and the 'hexapole' construction -- more even torque, better division of resistance heating over more windings, etc.
Note that EMD ultimately went to permanent parallel connection with the advent of true high unit horsepower... using many multiple taps of motor field weakening.
From what I have read and nobody has talked about is, the electricals didn't switch from series to parallel in Baldwins diesels like the EMDs did. Which is probably why the Baldwins have good lugging power and good wheel slip control to go with it. If somebody on this forum has a better understanding of the wheel slip control, I'm all ears.
Jim F
CSSHEGEWISCHThe problem with the J's re-powered centercabs was matching a 567 engine running at 950 RPM with a Westinghouse generator designed for a De La Vergne engine running at 625 RPM. No wonder that EMD wanted to replace the electricals.
The problem with the J's re-powered centercabs was matching a 567 engine running at 950 RPM with a Westinghouse generator designed for a De La Vergne engine running at 625 RPM. No wonder that EMD wanted to replace the electricals.
Well, there you go; another great "lugging" story for Baldwin. :)
Perhaps you meant to say Baldwin S-12? As others have pointed out the H12-44 was an FM product, and from all I read they were great "luggers" as well (with one of a kind blue-white exhaust).
Yes, the way CalDreamer described it, it was definately an FM. SP rostered a fair number of FM's particularly Trainmasters for passenger service.
Thanks; the answer theme appears to be traction motor differences vs prime mover.
Thank you; that's something I never thought of. I'm always thinking prime mover on these type things.
The branchline that ran through my hometown when I was growing up generally used a single Baldwin VO-1000 or DRS 6-6-1500, or a single FM H-10-44 or H-12-44, on their freight trains. When they changed over to EMD switchers (SW-1200s and SW-1500s) they always used two for the same size trains.
OvermodIs that different from the 'burly Baldwin brutes' section in A Railroad Life volume 2?
No, it was from an article in TRP (Trains and Railroads of the Past) magazine. It's been several years so I don't remember which issue.
I've got several of those Pechulis videos, the Jersey Central series, and the quality it first-rate! Astounding actually, Mr. Pechulis takes 8mm films and when he's done with them you'd swear they were shot on 16mm!
Flintlock76Lehigh Valley veteran Mike Bednar wrote an article several years ago about the Lehigh Valley's Baldwin switchers.
Lehigh Valley veteran Mike Bednar wrote an article several years ago about the Lehigh Valley's Baldwin switchers. He said they were very popular with the crews, who were sad to see them go when the Valley rationalized their switching power with EMD products.
http://baldwindiesels.railfan.net/sms/index.html
Currently, SMS Rail Services in New Jersey has an interesting stable of Baldwin diesels they use in everyday services. As I understand it they do enjoy showing them off IF you make prior arrangement for a visit, don't just show up and expect a tour.
Overmod Backshop H12-44 is an FM model. Could you have meant something else? To my knowledge all the SP H12-44s had the same Westinghouse 362-Ds as their S12s, and would presumably have the same lugging characteristics...
Backshop H12-44 is an FM model. Could you have meant something else?
To my knowledge all the SP H12-44s had the same Westinghouse 362-Ds as their S12s, and would presumably have the same lugging characteristics...
BackshopH12-44 is an FM model. Could you have meant something else?
SP had a fair amount of S-12's and was ready to place another order when Baldwin quit.
H12-44 is an FM model. Could you have meant something else?
I can attest to he lugging ability of the Baldwins. I was in the SP's Santa Clara, California tower and the operator and I were amazed as a Baldwin H12-44 switcher pulled 150 cars out of the bowl yard as he switched them on to the east bay line headed to Oakland. The train was going no more than a couple of miles per hour as he pulled the train, smoke pouring out of the stack. The engineer reversed the move and shoved the cars back onto another track. To this day I still cannot beleive how well that little lugged. That is why they are my favorite switcher.
VGN JessAlmost universally, as far as I have read, railroad men have spoken admirably about the "great lugging ability" of Baldwin diesels. But I have never understood the "why".
The generators likewise were designed for full amperage at lower rpm (peak you'll recall being 625rpm).
I have told the story here a couple of times that was related by R.J. Russell, a Metroliner engineer in the early '70s who had run the BP-20s in commuter service. What I recall him saying was that it was common to see the ammeter 'peg' at something over 2000A for up to a minute or so after each start and then come sagging down... lather, rinse, repeat to Long Branch or Bay Head and then back. This may put the comments about these Baldwins having to be operated in pairs because of 'reliability' concerns in some perspective... and remember these were retired from service more through motive-power rationalization planning (and a surplus of available E units as long-distance passenger service imploded).
This also puts teeth in Louis Newton's observation about one reason for the N&W TE-1's retirement being substantial traction-motor damage. You can read this in Rails Remembered, volume 4 (Tale of a Turbine) -- pay careful attention as you read to the consequences of generator drop damage. There are detailed pictures in the NWHS archives of the turbine impact damage from the 'little mistake' they had switching; I wouldn't be surprised to find documentation of the traction-motor damage Newton described there too.
The GE counterpart included the rightly-famous 752. Fortunately we have had a couple of posts from knowledgeable authorities on detail-design improvements on GE ocomotive traction-motor provision over the first-generation years, including one regarding the GE response to 'streetcar motor' complaints when the first ATSF 'DL-109' pair had trouble on Raton Pass. It might be interesting to compare PRR's experience with E units in TrucTrain service to EL's with PAs in fast freight.
More knowledgeable individuals around here will hopefully pop in later and elaborate, but in the meantime I can tell you that a significant reason is Westinghouse and GE electrical gear.
The somewhat overbuilt traction motors used by the minority builders could be pushed harder since they could tolerate a lot more abuse than EMD's own, thanks to having a lot more copper in the windings and so on. EMD's electrical systems of similar vintage were also sometimes slower to load than the competition, which is important if you're an engineer having to switch with one.
So you'd find FM's, Baldwin's, Lima's, and Alco's in what often seemed to be some of the harshest assignments where heavy and sustained slow speed lugging was important, taking advantage of a major virtue of them compared to EMD's designs.
EMD's traction gear was lighter built and designed for the average job, and would quickly fail if abused similarly. The competitor's was overbuilt for most assignments, more expensive to purchase, and when a traction motor needed to be rewound, more expensive to do than an EMD motor (Albeit with a frequency less than an EMD).
EMD's of course could still respectably handle such jobs as long as the ratings for the motors were respected, but it was one of the few areas where the products of the minority builders had an advantage over La Grange.
Almost universally, as far as I have read, railroad men have spoken admirably about the "great lugging ability" of Baldwin diesels. But I have never understood the "why". With only 8 cylinder in-line engines (and with ALCO V-12's and EMD V-16's, not lugging nearly as well), does anyone have knowledge or thoughts as to why Baldwins pulled slow but so hard? I have read the Dolzall's book on Baldwin Diesels and neither address that question. Thanks.
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