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  • Penn Station turnaround for Empire Connection?

  • Discussion related to Amtrak also known as the National Railroad Passenger Corp.
Discussion related to Amtrak also known as the National Railroad Passenger Corp.

Moderators: GirlOnTheTrain, mtuandrew, Tadman

 #1511980  by east point
 
Backshophoss wrote: Sat Jun 22, 2019 5:40 pm To change the PRR grid to 60hz power is not cost effective,and Amtrak has invested in keeping the PRR grid reliable.
Swappping power feeds for the Tunnels and Penn Station not easy and the NJT Arrows are not setup for "on the fly" main transformer
tap changes,not sure if the AL45 DP can "change taps" on the fly as well,they only change modes at station stops at present. :(
You are making a assumption not based in fact. Tap changing only has to occur when changing voltages. There is no tap change wen changing from PRR 12.0Kv 25 Hz to the MNRR 12.5 60 Hz. Tap changing does occur when mid town direct trains come off NJT onto the Amtrak NEC. Also tap changing occurs when Amtrak trains leave New Haven going toward BOS.
 #1511982  by David Benton
 
Correct. The only advantage to changing to grid frequency, would be when replacing power supply units . 60 hz would only require a transformer, whereas 25hz would require a rotary converter, or "solid state" converter, (these days a big version of the switchmode power supply for your laptop etc).
 #1511984  by Backshophoss
 
Change the Voltage=Change the Tap,Change the Hertz-Change the tap
E60's,AEM-7's,ALP-44's,ALP-46'sAcela I power cars,HHP-8's,and ACS-64 can handle all 3 NEC voltages.
AL45-DP can handle 2 out of the 3 voltages(PRR 13.2 kv. M&E 25kv)
Arrows required shop time at MMC to change between the M&E or PRR side unless NJT finally installed tap changers on the Arrows.
Before ConnDOT went to 60hz power,GG-1's,Metroliners,a small bunch of MP-54's(New Canaan Branch)and in theory the Arrows could run to
New Haven Conn.
So far,only NJT's ALP-46 has operated on the MN grid east of CP gate.
MARC's HHP-8's have made it to Boston.

Dual mode diesel/3rd rail Locos have been and will be the Empire service power. it WORKS and does the job.
 #1511997  by mtuandrew
 
Messrs Rich and Hoss: exactly, it won’t happen until Safe Harbor is due for another rebuild. Do any of the European systems still use... what is it, 13 1/3 Hz frequency? Or has everything converted over to 50 Hz?
 #1512004  by electricron
 
mtuandrew wrote: Sun Jun 23, 2019 7:20 am Messrs Rich and Hoss: exactly, it won’t happen until Safe Harbor is due for another rebuild. Do any of the European systems still use... what is it, 13 1/3 Hz frequency? Or has everything converted over to 50 Hz?
Yes, Norway still uses 15 kV  16.7 Hz AC on all their electrified train corridors. No need to look for more countries since it answers your question.
 #1512009  by SRich
 
mtuandrew wrote: Sun Jun 23, 2019 7:20 am Messrs Rich and Hoss: exactly, it won’t happen until Safe Harbor is due for another rebuild. Do any of the European systems still use... what is it, 13 1/3 Hz frequency? Or has everything converted over to 50 Hz?
Germany and Austria have 15 kV 16.67 Hz. But the rest of the EU is going to 25 kV 50 Hz
 #1512027  by WhartonAndNorthern
 
Backshophoss wrote: Sat Jun 22, 2019 8:58 pm Change the Voltage=Change the Tap,
Correct, a voltage change means the ratio of transformer coils needs to change therefore the movable taps need to be adjusted. This must be done manually on the Arrows.
Change the Hertz-Change the tap
No. As long as the transformer is designed for 25 Hz (large iron core), it will handle 60 Hz.

The bigger issue is the impedance bonds between track sections are likely tuned for DC and 25 Hz not DC and 60 Hz. These bonds allow breaks in the track signal circuit for signalling blocks but allow power currents to return to ground. These would all need to be replaced to do 60 Hz, even without a voltage change.

Also the signal power is 25 Hz or derived from 25 Hz. So either signal equipment needs to be replaced or converters need to be added. I'm not sure if each signal is fed from it's own transformer or if there's central signal lines that could be equipped with converters. It might be the whole signal system is 91 2/3 Hz and you just need converters at selected points.

Although if 25Hz is gone, signal power could revert to 100 Hz (PRR's usual standard). Apparently there was an interaction between 25 Hz and the DC offset from 3rd rail current that caused a nasty 4th harmonic at 100 Hz, hence the 91 2/3 Hz signal frequency.
 #1512042  by SRich
 
mtuandrew wrote: Sun Jun 23, 2019 10:22 am Ok, thanks, that answers my question about whether the US is the only country still using legacy power. Guess those two will be buying heavy transformer-equipped power for a while too.
In the Netherlands every new electric loc (1.5kV DC/25 kV)is rectified to DC and then thru inverters convert to 3 phase AC for the traction motors
 #1512043  by DutchRailnut
 
not only Netherlands any AC propulsion locomotive works like that . many locomotives no longer have transformers the DC choppers kill the AC to manageable DC for AC inverters.
 #1512047  by Nasadowsk
 
mtuandrew wrote: Sun Jun 23, 2019 10:22 am Ok, thanks, that answers my question about whether the US is the only country still using legacy power. Guess those two will be buying heavy transformer-equipped power for a while too.
Sweden, Switzerland, Austria, Germany are all 15kv 16 2/3rd.

All other AC systems out there are 50 or 60Hz, save for Amtrak's 25hz. I think there's an Austrian one that's 25hz, but only a few kM long. Might be three phase, too.

I have a nagging suspicion that at least in some instances, notably Germany, the transformer is a space heater that has the side effect of dropping voltages. I've seen pictures of the Class 103's main transformer. I can't accept that that thing was rated anywhere near what's claimed of it.

The stuff works though. *shrug*

But, the European legacy systems are not only huge (Germany at one time had even nukes that generated native 16hz traction power), but plenty of 'legacy' equipment that can't change frequencies. I saw some DB Class 111s at Stuttgart last October. Very interesting noises as they pull out... SBB and BLS still runs some antique stuff, SJ might too.

I've yet to hear a good reason beyond the sunk cost fallacy why the NEC can't be at least incrementally converted to 60Hz traction power (and yes I've read that 'paper' from someone at Amtrak back in the late 70's - was a cute argument except that all modern AC rail equipment runs a unity power factor, rendering the guy's excesses to retain 25hz moot).

I'd be curious what the cost savings by not having to absorb the losses in frequency conversion alone would be...
 #1512048  by Backshophoss
 
There's a substation in NJ(PSE&G) that has a rotary converter and a pair of Static Inverters that handles everything for NY Penn,Sunnyside and to CP Gate.
W&N you hit the reason why the FRA is unhappy with NY Penn,the "grandfathered" dual power source setup there.
At the end of Cos Cob existent as a generator station ,there was a rotary converter there tied into CL&P grid.
Anybody know if that converter was stored or scrapped after the conversion to 60 hz power?

Amtrak may have had long talks with NJT about the M&E conversion from DC to 25 kz AC,and
with ConnDOT about the conversion from 25hz to 60hz power on the New Haven line.
Along with new insulators everywhere on the Catenary,bridge raisings to provide proper air gaps.
Rebuilding/replacing substations and the transmission grid as needed.
Last edited by Backshophoss on Sun Jun 23, 2019 5:42 pm, edited 1 time in total.
 #1512049  by DutchRailnut
 
it was sold to out of state customer and moved via Springfield line , despite move being scheduled via Berkshire line including the line fix at Boardman Bridge.
 #1512682  by ThirdRail7
 
Jeff Smith wrote: Thu Jun 13, 2019 1:20 pm One other consideration: http://www.rethinknyc.org/through-running/

NJT and MNRR really need to jump on this, as it's possible now. And, if they can figure it out, MNRR and LIRR.
Every time someone mentions through running, it makes me cringe...particularly on days like today.

A catenary car caught on fire today, just outside of Hamilton, NJ. Take a look for yourself:

Amtrak rail train catches fire at Hamilton rail station
https://www.youtube.com/watch?v=pNn_MNg-fv8

This incident caused the railroad to close for hours as firefighters needed the catenary off to fight the blaze. This decimated not only Amtrak but crippled NJ transit's rush hour. They're still reeling hours later.

Yesterday, a bridge failure knocked NJT off balance.

As bad as this is, imagine if you needed that equipment to run through to ANOTHER railroad operation. Now, you've crippled the entire region. A grade crossing accident in Mineola will impact a passengers travelling on SEPTA. A fire in Hamilton could potentially mess with equipment for Metro-North.

It is a bad idea all around.
 #1512710  by EuroStar
 
And that is why through-running is done practically everywhere in Europe with no ill consequences. Thank you for scaremongering. It does help though that the Europeans generally keep their stuff well maintained and do not pinch pennies on capital improvements.

Anyway, through running in NYP does not mean that every train needs to run through. You can get meaningful benefits by running through every fourth train, while still turning the rest the way it is done now. This gives you enough robustness to take a hit from events such as yesterday, without collapsing the service. You can probably go as far as through running every other train and still have enough robustness in the schedules.

The other thing you need to do is to allow the dispatchers to make certain routing decisions on the spot, specifically short turn trains in the case of a disruption such as yesterday. The short turns will end up replacing the "missing" through-runs. For example if we had through running New Haven-Trenton and yesterday happened, at some point the Trenton originating train set is "missing" and cannot make its run east of NYP, but you have the set that came from New Haven and cannot go to Trenton anyway, so just short turn it on the day of the disruption and you have solved the major rush hour issue. Yes, a few people who ride through get inconvenienced in having to disembark at NYP when they usually do not need to do that, but they could not go west until the fire issue is resolved anyway. The issue of crews not ending where they started is easily solvable by having the through-runs always change crews an NYP (which with current union rules you will need to do anyway).

I do have to give you that NJT and Amtrak are particularly terrible on scheduling/dispatching and infrastructure respectively, because they could not run even to New Brunswick/Jersey Avenue during the fire yesterday.
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