ALL:
Do passenger locomotives with HEP have an extra diesel engine to provide power for lighting, etc. if the locomotive itself dies on the road. I know that the BNSF has provided a freight locomotive for the EB is the AMTRAK locos die.
Ed Burns
Retired Class 1
NP EddieALL: Do passenger locomotives with HEP have an extra diesel engine to provide power for lighting, etc. if the locomotive itself dies on the road. I know that the BNSF has provided a freight locomotive for the EB is the AMTRAK locos die. Ed Burns Retired Class 1
As the old saying goes - It Depends.
The Amtrak F40-PH's used the prime mover of the locomotive to generate HEP, that is one reason if you saw a Amtrak train stopped with a F40-PH on the head end it sounded like it was doing 60 MPH. The prime mover and generator did not develop HEP power at prime mover idle. I believe, and I can be sadly mistaken, the prime move had to be spinning at Notch 5 level or higher for proper HEP to be generated.
When Amtrak requested CSX power for moving trains account engine problems - it was for CSX to move the train, NOT supply HEP power to the train. In my experience, when Amtrak had engine failure that included HEP failure in most all cases arrangements were made to bus passengers to destination.
I have no working knowledge about any other form of Amtrak locomotives.
Never too old to have a happy childhood!
Lots of "passenger locomotives" have separate diesels for HEP, at the rear of the unit, and a few of those units pull Amtrak trains, but most (all?) units that say "Amtrak" on them get HEP off the traction diesel.
When HEP started, it was always supplied by a separate diesel. Guess the U34CHs were the first to use the traction diesel, around 1970?
About the just depends statement. Almost all AC traction locos now being built use the prime mover. Since inverter(s) are needed for traction either an output on the inverter or a separate inverter provides HEP. Example the SC-44s take power from the prime generator 0( alternator) rectify it and send the output thru an inverter that provides 600 Hz 480V 1000Kw power. A very reduced speed of the diesel provides enough current for the HEP. What actual speed needed will have to be provided by others.
The ACS-64s have 2 innverters each rated at 1000Kwthat provides reduntant power as long as it can receive power from the CAT.
What about the SD70MAC's that METRA is leasing from BNSF? Does anyone know how they wil be modified to provide HEP power to the cars?
Caldreamer
When I was working for the railroad in Alaska a few years ago, the passenger cars would get HEP power that was diverted from one of the trucks on the SD70 MACs. They said one SD70MAC would power about six cars. On our passenger cars all of them had diesel generators. One generator could power two cars if they were running A/C or heaters. If they were running neither then you might be able to run four cars from one car. Running the diesel generators were expensive so getting HEP from the locomotive is much better and cheaper.
BaltACD The Amtrak F40-PH's used the prime mover of the locomotive to generate HEP, that is one reason if you saw a Amtrak train stopped with a F40-PH on the head end it sounded like it was doing 60 MPH. The prime mover and generator did not develop HEP power at prime mover idle. I believe, and I can be sadly mistaken, the prime move had to be spinning at Notch 5 level or higher for proper HEP to be generated.
The electrical equipment on Amtrak's passenger cars is designed for 60Hz. Prior to widespread use of inverters for AC traction motors, the need for 60 required that the prime mover be turning at a submultiple of 3600rpm, i.e. 1800, 1200, 900, etc.
You were not mistaken with respect to the F40-PH.
Erik_Mag BaltACD The Amtrak F40-PH's used the prime mover of the locomotive to generate HEP, that is one reason if you saw a Amtrak train stopped with a F40-PH on the head end it sounded like it was doing 60 MPH. The prime mover and generator did not develop HEP power at prime mover idle. I believe, and I can be sadly mistaken, the prime move had to be spinning at Notch 5 level or higher for proper HEP to be generated. The electrical equipment on Amtrak's passenger cars is designed for 60Hz. Prior to widespread use of inverters for AC traction motors, the need for 60 required that the prime mover be turning at a submultiple of 3600rpm, i.e. 1800, 1200, 900, etc. You were not mistaken with respect to the F40-PH.
F40PH notch 8 speed was 896 RPM, so gearbox driven HEP would put out 60Hz. Normal 16-645E3 speed schedule was 904 RPM for N8.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
If I recall correctly "Trains" ran an article, maybe last year, on the Via Rail (Canada) F40 rebuilds. Via installed separate small diesel engines in the locomotives independent of the prime mover to provide HEP, so no more Notch 5 settings (or higher) are needed to provide the juice.
oltmannd F40PH notch 8 speed was 896 RPM, so gearbox driven HEP would put out 60Hz. Normal 16-645E3 speed schedule was 904 RPM for N8.
You're overthinking things.
HEP on an F40 is implemented using the existing D14 'companion alternator' provided for main-generator excitation, wired to provide native three-phase to the HEP cabinets. This accounts for the governed 893rpm (the manual's figure, mentioned several times so unlikely to be a misprint) for nominal 60Hz output; the 'traditional' D14 ratings are for rectified output voltage rather than frequency matching.
A completely separate function provides the 'standby' power source, which is the 720rpm native 60Hz output off the (ten-pole) AR10 main alternator. There are specific instructions (and a description of the cutover sequence) involved in transitioning to standby from companion-alternator HEP and vice-versa.
Flintlock76 If I recall correctly "Trains" ran an article, maybe last year, on the Via Rail (Canada) F40 rebuilds. Via installed separate small diesel engines in the locomotives independent of the prime mover to provide HEP, so no more Notch 5 settings (or higher) are needed to provide the juice.
Yes, the genset is powered by a CAT C18. To make room for it the rebuilds lost their rear platform/walkway and gained a hump atop the rear of the long hood:
In the mid 1990s VIA had HEP gensets added to their few remaining FP9's, these were powered by a Detroit Diesel Series 92. Unfortunately those units only saw service for a few years, being retired in the early 2000s when the GE P42's arrived.
These two have been restored to their original appearance, and still contain their HEP gensets:
http://www.railpictures.ca/?attachment_id=34316
Greetings from Alberta
-an Articulate Malcontent
Other approaches to installing HEP gensets exist. Here is part of a post from a different forum regarding the installations on the Boston "T":
mbta1051dan When the F40PH-2C first came out, it was delivered with the Cummins VT1710, V12, HEP Generator. Around 1997, when the Geeps arrived, they replaced them with the then-standard Cummins KTA19, although they weren't as loud as the Geeps because they were enclosed. When they were rebuilt at Boise, they got today's standard HEP generator, the Cat 3412. The Boise F40PHM-2Cs were different. They were actually delivered with Cat 3406s (the same used on all Boise "F40 Clones" at the time), and these were quite noisy, but were rebuilt with the 3412s around the same time as the -2Cs. The GP40MCs are probably notorious for very loud HEP generators ... They are Cummins KTA19s, but the characteristic 60Hz "buzz" sound is created by the extremely loud overhead electrically-driven radiator fan. This four bladed fan is, most likely, an EMD factory fan, similar to the radiator fans for the prime mover, and the ones on the screamers. This fan also tends to cycle on or off. They aren't too loud when off, but you never know when they'll cycle on.
When the F40PH-2C first came out, it was delivered with the Cummins VT1710, V12, HEP Generator. Around 1997, when the Geeps arrived, they replaced them with the then-standard Cummins KTA19, although they weren't as loud as the Geeps because they were enclosed. When they were rebuilt at Boise, they got today's standard HEP generator, the Cat 3412. The Boise F40PHM-2Cs were different. They were actually delivered with Cat 3406s (the same used on all Boise "F40 Clones" at the time), and these were quite noisy, but were rebuilt with the 3412s around the same time as the -2Cs. The GP40MCs are probably notorious for very loud HEP generators ... They are Cummins KTA19s, but the characteristic 60Hz "buzz" sound is created by the extremely loud overhead electrically-driven radiator fan. This four bladed fan is, most likely, an EMD factory fan, similar to the radiator fans for the prime mover, and the ones on the screamers. This fan also tends to cycle on or off. They aren't too loud when off, but you never know when they'll cycle on.
'70Dude, those are some gorgeous restorations of those FP9's! What a classy paint scheme as well, too bad CN dropped it. I can understand why, I'm sure it was expensive, but still...
Overmod You're overthinking things. HEP on an F40 is implemented using the existing D14 'companion alternator' provided for main-generator excitation, wired to provide native three-phase to the HEP cabinets. This accounts for the governed 893rpm (the manual's figure, mentioned several times so unlikely to be a misprint) for nominal 60Hz output; the 'traditional' D14 ratings are for rectified output voltage rather than frequency matching. A completely separate function provides the 'standby' power source, which is the 720rpm native 60Hz output off the (ten-pole) AR10 main alternator. There are specific instructions (and a description of the cutover sequence) involved in transitioning to standby from companion-alternator HEP and vice-versa.
Thanks for the link to the manual. 893 - hey, my memory was close.
The D14 doesn't do HEP. Items 21 and 23 in the general arrangment are the gearbox and HEP generator. My Amtrak friends have told me the gearbox was a PITA....
oltmanndThe D14 doesn't do HEP. Items 21 and 23 in the general arrangement are the gearbox and HEP generator...
So, to be clear: there are two separate D14s on the diesel engine, one that excites the main generator in the normal way, and one that is dedicated to 3-phase AC generation. Right?
Can someone find a good photograph of the generator end of one of these setups that shows the arrangement?
Interesting that a one-speed gearbox would be a PITA -- they probably forgot to implement the right combination of flexible drive and zero backlash necessary to give stable 60Hz under varying load and found all sorts of tooth and bearing damage over time...
Just as a note for Erik: the issue with a multiple-speed gearbox is that the logic to interlock stable 60Hz with 'standby' involves vastly more complexity and potential points of failure when you add the necessary interlocking of gearbox and governor to get "low speed" 60Hz when the locomotive is needed for normal train handling and would need repeated cycling to and from run 8 without interrupting HEP delivery to the consist. One problem with F40 HEP as designed is that no other source of AC can be connected when any function is active, so even 'shore power' has to be interrupted for a while when you switch from front-end generator to standby or back again. Imagine the fun even if you could automate the necessary switching between slow and fast gear speed!
Suspect the answer to this issue in the short run involved static inverter HEP, with some voltage clamping and/or buck-boost voltage adjustment to the inverter to compensate for the variation in DC voltage from a D14 with rectification as the DC-link source for it. That gets rid of all the 60Hz (and probably power factor) issues, and at least provides a simple path toward reasonably stable RMS voltage on the HEP bus with varying engine speed...
Someone who knows, please comment on whether spikes or other 'unclean' power considerations were trouble on the early non-genset F40 setups.
That F40 manual says the HEP "generator" produced 60 Hz at 1800 RPM, so it seems to be geared all right.
"there are two separate D14s on the diesel engine"
No one said that, did they?
timz"there are two separate D14s on the diesel engine" No one said that, did they?
Manual says (at least twice) that the HEP generator is a D14.
No one is denying, to my knowledge, that excitation on an F40's AR10 is done with a D14.
Don says the excitation D14 isn't used for HEP, and of course vice versa.
You figure it out.
Overmod timz "there are two separate D14s on the diesel engine" No one said that, did they? Manual says (at least twice) that the HEP generator is a D14. No one is denying, to my knowledge, that excitation on an F40's AR10 is done with a D14. Don says the excitation D14 isn't used for HEP, and of course vice versa. You figure it out.
timz "there are two separate D14s on the diesel engine" No one said that, did they?
There is only one D14 on an F40. The HEP generator is a whole different animal in size and shape.
oltmannd Overmod timz "there are two separate D14s on the diesel engine" No one said that, did they? Manual says (at least twice) that the HEP generator is a D14. No one is denying, to my knowledge, that excitation on an F40's AR10 is done with a D14. Don says the excitation D14 isn't used for HEP, and of course vice versa. You figure it out. There is only one D14 on an F40. The HEP generator is a whole different animal in size and shape.
This is what comes of reading the manual on a phone, in the dark. None of that 'second D14' information even makes sense. Would still enjoy pictures of what's actually there, though.
At least I can verify that the mechanical step-up on the F40 is exactly 2:1, 900 to 1800, per the manual. This leaves us absent the reason for the nominal 893rpm speed -- power factor in rotating HVAC compressor drives? Bet Don can find someone with the definitive answer...
All the references I remember with equipment layout and description for the U34CH appear to be gone. Will Davis may be the appropriate source for description or pictures of the particular HEP alternator arrangement, or the traction-alternator excitation arrangement, on this locomotive. I recall the U34CH operating at continuous prime-mover speed (at what we thought was 900rpm) with passengers on the train, while in freight mode they were allowed up to 1050rpm -- you got some pretty good shows when the fuel was applied for a fast start toward River Edge with the engine already turning at what amounted to high-notch speed.
I see secondary sources that refer to an actual shaft off the 'alternator PTO' to drive the HEP alternator (which was behind the cab in the place usually reserved for a blower; would that not be at the other end of the engine from anything likely driving a radiator fan?) The problem is that 'shaft driven' doesn't always mean a physically separate driveshaft to a separately housed alternator.
Overmod Interesting that a one-speed gearbox would be a PITA -- they probably forgot to implement the right combination of flexible drive and zero backlash necessary to give stable 60Hz under varying load and found all sorts of tooth and bearing damage over time... Just as a note for Erik: the issue with a multiple-speed gearbox is that the logic to interlock stable 60Hz with 'standby' involves vastly more complexity and potential points of failure when you add the necessary interlocking of gearbox and governor to get "low speed" 60Hz when the locomotive is needed for normal train handling and would need repeated cycling to and from run 8 without interrupting HEP delivery to the consist. One problem with F40 HEP as designed is that no other source of AC can be connected when any function is active, so even 'shore power' has to be interrupted for a while when you switch from front-end generator to standby or back again. Imagine the fun even if you could automate the necessary switching between slow and fast gear speed!
The reduction gears used on the large radial engines would have been an interesting starting point for a gear drive between the locomotive prime mover and an alternator. The prop acts like a huge flywheel as does the alternator. Said large engines often had a two speed supercharger, though the speed change was probably done closer to the impeller RPM than the crankshaft RPM. OTOH, the reduction gears were PITA to maintain.
The ability to connect with "shore power" is more of a function of the governor than anything else, you need the ability to match the engine speed to the external power, the rest is pretty standard synchronization of alternators. A few of the early UP HEP equipped Streamliners had provisions for synchronizing the two engine sets - and a bit more far afield was the two 400Hz APU's on the YB-49 could also be synchronized.
Erik_MagA few of the early UP HEP equipped Streamliners had provisions for synchronizing the two engine sets -
Apparently, the P30CH's originally could syncho the HEP engine gen sets they had on board. I don't think that lasted long, though.
I remember doing an engineering lab at school where we sychrod a motor gen set to the grid. We had to match speed then, watch the phase angle. When it was close, throw the knife switch and watch the speed "lock on" to the grid frequency.
I had a couple of quarters of power systems lab at Cal, sounds like we were using a similar set-up with a DC motor driving and AC 3 phase generator. We usually used a line synch'ed stroboscope for phasing, but used the lights on occasion. The strobe was mainly used to show the shaft (power) angle with repsect to the line and it was rather impressive watching the angle vary when we simulated power system faults.
Erik_Mag . A few of the early UP HEP equipped Streamliners had provisions for synchronizing the two engine sets - and a bit more far afield was the two 400Hz APU's on the YB-49 could also be synchronized.
. A few of the early UP HEP equipped Streamliners had provisions for synchronizing the two engine sets - and a bit more far afield was the two 400Hz APU's on the YB-49 could also be synchronized.
Interesting details about paralleling alternators on airliners. The note about the YB-49 APU's was from a ca 1975 reprint of the YB-49 operations manual, with the APU's being powered by air-cooled Franklin engines. The neon light synchronizer works the same way as power system synchronizing lights, with 3 lights being used to ensure the same phase sequence. Heard a story of what happened when a large (probably 50 to 100MW) turbo-alternator was connected in reverse sequence - the alternator was torn from the foundation.
The HEP equipped UP Streamliners used separate circuits for the two genset and the electrical panels on the cars had provisions for which circuit was selected for powering the HVAC.
Synchronizing two prime-mover powered HEP's is asking for trouble unless the HEP alternators can handle the full output from the prime mover. Smaller HEP alternators could pull out if the governors didn't maintain close control of the relative crankshaft position. This is a solvable problem as multi-engine propeller driven planes have had that capability prior to WW2, but would probably be more trouble than it is worth for locomotives.
I can't give a technical description or quote any specs; I can just tell you about the locomotives used by Metra.
When I started, all suburban power was either F7s or E8/9s. All units had a Cummins engine in the rear of the unit, mounted transversally to the prime mover, which made it quite difficult for a person to walk from the train to the cab without getting very dirty from all the oil those nasty engines sprayed all over the interior of the engineroom. This Cummins engine really roared when up to speed (probably the 1800rpm previously mentioned). One Cummins engine would be sufficient ot power a train of 11 bi-level coaches in any temperature extreme.
The F40 had only the prime mover which also provided HEP. It had a "stand-by" mode, where the only HEP would be supplied. It kept the engine speed at around a 5th notch equivalent. The controls were in the cab (as opposed to the Cummins, which had to operated from a cabinet at the rear of the carbody). It took about a minute after "stand-by" power was switched off for the locomotive to develop motive power (or from motive power to HEP). When the loco was in "normal" mode and the HEP was switched on, the prime mover would run at constant full speed.
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