Southern Pacific purchaced four GP40X locomotives in 1978. Two were set up as Locotrol Master's and two as Remotes. Does anyone know what service the four were ordered for? The SD40T-2 units set up for Locotrol were used over Tehachapi in general freight service and on the "Oil Cans" tank train.
From accounts I've read by former SP crewmen on other forums, the GP40Xs were initially used in sets on hot pig trains up the coast. The Locotrol/Master units were paired up in the consist, but the Locotrol/Master pairs were NOT MU'ed (hopefully this makes some sense). Something along the lines of Master+Remote-Master+Remote. That way, the lead pair of GP40Xs would be online, while the trailing pair would be in remote mode, adding HP as commanded by the engineer in the leading set, theoretically saving fuel since they would only be brought online as needed. Hope that makes some sense!
Thanks for the reply. If I'm understanding it correctly the Master/Remote units were coupled together in the same consist but not MU'ed but operated as a Master/Remote set?
That's how I understand it. I never saw the GP40Xs until after the Locotrol days were over. I'm not sure of the time line, but maybe the GP40X Locotrol was to test feasibility for the SD40T-2s. It doesn't seem there would be much need for Locotrol along the coast. Just thinking about this...seems like MUing is such a simple solution. Maybe for DPUs though.
From all accounts, the idea behind the GP40X locotrol testing on the coast was mainly for fuel conservation reasons; remember, they came out in the late 70s, when fuel prices were high and the RRs were looking towards lowering fuel costs. If trailing units could be easily taken on/offline as needed to maintain track speed, all the better. At the time, the only other way to take a trailing unit offline in a consist would be to send a crewman back to the unit and isolate it, and reverse the process when it's needed again. Not very safe or convenient!:tb-wacky: The Harmon Select-a-Power system, which SP also reportedly later installed in some GP40-2s (and which Conrail went for in a big way) could allow the engineer to idle/activate similarly equipped trailing units in a consist via commands passed through the MU cable. And FWIW, I doubt Locotrol in the GP40Xs had anything to do with Locototrol in the SD40T-2s; the GP40Xs were built in 1978, and SP had long since taken delivery of Locotrol-equipped SD40T-2s, the first being SP 8300 built in 1974. By the time the GP40Xs came along, SP likely had a pretty good idea of the capabilities of Locotrol.
They haven't... GE Transportation - North America : Products : Locomotive Products : Onboard Systems : LOCOTROL Distributed Power
At least as far as SP and their T-2s and GP40Xs were concerned, AFAIK they gave up the widespread use of Locotrol in the early/mid-80s. Too many problems with radio continuity with the early systems.
Am I wrong or are those EMDs in the picture on that site? If DPU is really just Locotrol, I wonder why the name change? You would think GE would want to toot that horn. Is their a competitor?
I guess my question is why we, the foamers and apparently the industry have genericized the name to DPU.
You can see some of it in this thread... say Locotrol and everybody thinks 60s-70s, even though the tech has advanced 30 years. The next step will be Locotrol by wire... completely elininating the radio.
I never remember the 8300's being used in remote service over the Tehcahapison the Oil Train. By the time SP started running the Oil Cans, they had given up on the 8300s in remote service. Now, I'm not saying you never saw an 8300 unit on the point and an 8351 in a helper set, but not as remote helpers. I could be wrong, but I worked as an engineer all through the 1980s on the Bakersfield/West Colton Pool, Run 951. One of the last times I even remember the remotes being used was, I was a fireman on a WCEUM. This was late 1979. I remember, Ray Knight was the engineer, the train was about 9800 feet long, I think 148 empties. We broke into at Woodford. Paul McGuffin
I saw an absolutely wonderful Espee GP40X model in H0 scale last Saturday. The guy said it was new, but I don't know who made it. It had the elephant ears and everything. Great commercial model!
Athearn would be the manufacturer. I have two 7200 & 7230 both by Athearn. I don't think there has been any other models made but could be wrong. A brass model might be out there.
Railpower Products made a GP40X also. Athearn bought them out, and their shell is based on the Railpower tooling w/upgrades.
