There is plenty of room inside an EF-4 carbody-the part where the contactors, relays and all the rest of the apparatus resides. BTW, the ignitrons were replaced with solid-state rectifiers. It appears that there is little chance of arcs jumping from any of the equipment or cables to ground.I've seen a few.
In comparison, the EP-5 was a case of 'five lbs of you-know-what'- stuffed into a 2 lb bag.' Main transformer (under the floor on modern locos), smoothing reactors, accelerating resistors, Vapor Boiler, contactors, relays, etc. I would guess an arc in the wrong place could cause some of the organic materials that were state-of-the-art to ignite. Wire jackets, insulating varnish, etc.
CPM500
Yes, frame. bowed by the heat. It could have been repaired-off line. Why that didn't happen should be easy to figure. Better to be parts-on-the hoof.
CPM500 The rectifiers did not cause fires on the EP-5's. ... PS-Some of us who populate this forum have actual first-hand experience with the equipment.
PS-Some of us who populate this forum have actual first-hand experience with the equipment.
I read that the EP-5"s suffered numerous fires because of their tight car body loco, vs the EF-4 freight rectifiers with more open road switcher type bodies, which didn't have this problem. I don't have the reference to re-read, but maybe I assumed they were inferring the mercury arc rectifiers were the cause, whereas I suppose any of the electrical components could have caused a fire. What was the cause of the fires?
CPM500The stated reason for retirement was 'structural damage.'
Structural damage from the frame being bowed by the heat?
Very interesting on the EMD mule project.
NW,
Having inspected the 503, I would say your account makes more sense that what was presented by the LIRR folks. The stated reason for retirement was 'structural damage.'
EMD had some interest in purchasing the hulk for a future project (static HEP mule), but the degree of cannibalization made the purchase a non-starter.
Thank you for that information, CPM.
Regarding Long Island 503, I think that was not a shoe fire, but rather the shopping cart connected the third rail with the body and that started the major fire?
On third rail speed, 108MPH is the record, with a British EMU. This was not very successful, and caused minor damage to both the train and the rail. About 100 is the safe maximum, IIRC.
NorthWestWeren't the shoe fires related to grease and dirt buildup on the rail?
I'll bet a hat Will Davis has material on this. But I suspect trash buildup was a less important reason for the damaging sorts of fires specific to multimode diesel/electrics. (I will cheerfully stand correction!)
Some of the problems were related to the need (in some cases) to accommodate both systems of third rail used in the NYC area (underrunning vs. overrunning).
Some of the problems related to switchover between electric and 'diesel' mode. IIRC the Baldwin-powered lightweight trains suffered severely from this; although I don't recall the specific mechanism that produced the woe, it has been covered and reasonably well-described technically. (What was that quote about 'another [short time interval] and I would have been a hero' that described one crippling fire right at rush hour?)
Meanwhile, I believe the speed limitation on third rail is related to the technical design of the shoes and contact apparatus, with a big concern being the geometrically-increasing current draw at the comparatively low voltage. There is also an increase in effects of mechanical damage to the pickup system, including effects from shoe bounce, at higher speed -- some of this might be helped with a servo-assisted pickup system, similar to what is used at much higher speed for catenary trolley-wire following. Someone is sure to argue that 600V nominal DC traction motors would be able to spin to full effective speed as easily on, say, 750V DC supply as they could from an onboard power source, and therefore there is no 'electrical' reason to limit the speed. I'll leave that discussion to y'all.
IIRC, the P32AC-DMs are limited to 80 MPH while on the third rail. So, there is a limit to the speed on electricity, but I think NJT could have gotten by with third rail diesels into the already equipped Penn Station for one seat rides, at a cost less than 7 Million apiece. Especially if they replaced the P32AC-DMs and DM30ACs at the same time, but these are only 15 years old, and can be rebuilt at least once.
Weren't the shoe fires related to grease and dirt buildup on the rail?
Overmod ... I'd like to think that the shoe and fire problems that were so evident in the '50s have been definitively solved with the '32s.
...
I'd like to think that the shoe and fire problems that were so evident in the '50s have been definitively solved with the '32s.
I knew the New Haven EP-5's had fire problems caused by their hot mercury arc rectifiers in the tight confines of the engine bodies designed for GCT. Later electrics solved the problem with solid state rectifiers. Did the FL-9's dual modes also have fire problems?
The key, I think, is that there is so much high-speed dieselized trackage in New Jersey, co-existing only with catenary electrification, and so much third-rail-equipped trackage in the New York area, that it is common sense to use dual-mode DC units in the latter (with the advantage of simplicity already mentioned).
I was presuming that the only use of third rail for trips through the Hudson tunnels would be within the tunnels themselves, and in the NYP complex on the New York end. This would be for things like the Manhattan Direct service (one of the things I recall the ALP45 dual-modes were destined for) where no operation past a Penn Station platform, "locomotive out" would be required, with push-pull trains where a short amount of diesel running in the tunnels (to make full transition to third-rail without extending the third rail substantially out past the portal) would not cause major discomfort. There would be no point in extending third rail further than the minimum required (it is in the tunnels to simplify working on the catenary), although a couple hundred feet of the right sort of third rail and the extended ties or base structures to hold it would not be 'big bucks' either to install or maintain.
Overmod MidlandMike NJT does not have the option of 3rd rail in the Hudson Tunnels. Well, yes they do; there's just little point in adding the DC equipment and shoes just to allow diesels to transit the tunnel. (They could use something like a P32DC from Empire service for that, as the things are 'hangared' right there at NYP, so if there were an advantage to it, I suspect that would have been tried.) Much more sensible (and, arguably, economical with respect to operating cost) is to make the diesel operable as a full AC electric when under catenary, where it can develop very high horsepower under conditions third-rail locomotives could only dream about. In part this pre-assumes a well-developed AC overhead-wire infrastructure... which exists for both NJT and SEPTA in a number of contexts. Note also that there is a somewhat restricted number of services that involve trips over trackage that is not fully wired, and not economical at this time to wire fully, but that require high speed and no engine change. One example of this was the Atlantic City Express operated with an electric at one end and a diesel at the other; this would have been a perfect service for an ALP-45DP... but would it generate sufficient revenue to justify the capital expense? Big place I'd expect this sort of power to be used by NJT would be service up to the 'fourth airport' at Stewart, with quick service to 'the other airports' via operation through the tunnels or over the portion of the NEC going to Liberty whatever-it's-called (I still just call it Newark Airport). Again, the politics of making this trick workable will likely outweigh the high first cost of the locomotives... at least, I certainly hope so. On the other hand, what you do with service to Stewart from a new line laid across at Tappan Zee is far less certain -- time to break out the tripower blueprints?
MidlandMike NJT does not have the option of 3rd rail in the Hudson Tunnels.
Well, yes they do; there's just little point in adding the DC equipment and shoes just to allow diesels to transit the tunnel. (They could use something like a P32DC from Empire service for that, as the things are 'hangared' right there at NYP, so if there were an advantage to it, I suspect that would have been tried.)
Much more sensible (and, arguably, economical with respect to operating cost) is to make the diesel operable as a full AC electric when under catenary, where it can develop very high horsepower under conditions third-rail locomotives could only dream about. In part this pre-assumes a well-developed AC overhead-wire infrastructure... which exists for both NJT and SEPTA in a number of contexts.
Note also that there is a somewhat restricted number of services that involve trips over trackage that is not fully wired, and not economical at this time to wire fully, but that require high speed and no engine change. One example of this was the Atlantic City Express operated with an electric at one end and a diesel at the other; this would have been a perfect service for an ALP-45DP... but would it generate sufficient revenue to justify the capital expense?
Big place I'd expect this sort of power to be used by NJT would be service up to the 'fourth airport' at Stewart, with quick service to 'the other airports' via operation through the tunnels or over the portion of the NEC going to Liberty whatever-it's-called (I still just call it Newark Airport). Again, the politics of making this trick workable will likely outweigh the high first cost of the locomotives... at least, I certainly hope so. On the other hand, what you do with service to Stewart from a new line laid across at Tappan Zee is far less certain -- time to break out the tripower blueprints?
I knew that the Hudson tunnels had 3rd rail to Manhattan Transfer before AC, but much was removed, except possibly within the tunnels. Even if there was operational 3rd rail in the tunnels, they would need a transition zone beyond.
MetroNorth gets by with their P32DC's under NEC wire. Are you saying their purchase and operation is less economic than the NJT's dual mode operation? To purchase the ALP-45DP you have to include the extra finance cost. It's hard to believe they will ever get a payback because of possible savings in electric mode.
While putting both full diesel and electric capabilities in one ALP-45DP seems technologically exciting, IMHO financially they are dogs. If they extended 3rd rail from NYP for empire service, they could have done the same for NJT and used P32DC's.
The politicians promised folks from Eastern LI a one-seat ride to NYC. Then the LIRR had to figure out how to deliver on this promise-hence the dual-modes.
7 MM a pop for the NJT units-is absurd-they couldn't have passed any ROI criteria. These transit agencies act like they print the money that they spent.
MRC and run electric only on the Penn Line and diesel only elsewhere. No need for dual mode. And when appropriate, it can also use diesel on the Penn Line. No need for dual-modes, which are expensive.
Not exactly true, Midland Mike..
The DC bus on a DM-30 'doesn't care' where the DC current comes from-either the TA-12 alternator or the Third Rail Cabinet. These locomotives can make track speed in either mode.The limitation is the substation network-not the locos.
On another note-NJT has a habit of sourcing locomotives from offshore, which as they age creates some challenges in sourcing renewal parts.
Dual mode locos were originally developed as primarily diesels with minimal electrical equipment to get them the last few slower miles into the underground Grand Central Terminal using 3rd rail. LIRR also uses them with Penn Station 3rd rail. The ALP-45DP are more like a both a diesel and a high power AC electric engine within a single loco (and are apparently priced accordingly). NJT does not have the option of 3rd rail in the Hudson Tunnels. Boston and MARC can get by with cheaper diesels, so why pay more? An ALP-45DP is more powerful as an electric, which would be a waste in the type of service the P32AC-DM sees.
In order:
MBTA: Receiving new diesel HSP46s from MPI.
MNCR: I'd expect them to wait and collaborate with Amtrak (and LIRR) to replace the P32AC-DMs (and DM30ACs) with a completely new locomotive, instead of trying to modify a dual mode.
MARC: possible, but they have enough MP36PH-3Cs for all diesel service, so dual modes may not be necessary. I think a ACS-64 variant is more likely, we will see.
zkr123 I am surprised by the lack of demand for the ALP-45DP by the other NEC based commuter railroads. They are perfect for MBCR's Providence line, and its branch lines. Metro-North could create a version thats diesel and third rail to supplement the aging P32AC-DM's, and MARC could use them as replacements for the HHP-8's.
I am surprised by the lack of demand for the ALP-45DP by the other NEC based commuter railroads.
They are perfect for MBCR's Providence line, and its branch lines. Metro-North could create a version thats diesel and third rail to supplement the aging P32AC-DM's, and MARC could use them as replacements for the HHP-8's.
Probably because they don't have a spare $7M laying around for one and what they have works well enough that there's no ROI.
What I'd like to see is the ROI for Amtrak's purchase. The AEM7 variants in Sweden are much older and still in service. Methinks Amtrak blew a wad of money on the wrong stuff. (like all those baggage cars) They would have been better off buying some coaches that actually generate revenue.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
It would be an expensive solution for MBTA to purchase a dual-power for the one line that is equipped with catenary when the existing diesel power works just as well.
Metro North probably got the P32's at a better price because Amtrak had already placed an order for the same model. They may be aging but they still work.
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