• Acela II (Avelia Liberty): Design, Production, Delivery, Acceptance

  • 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

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  by electricron
 
Ken W2KB wrote: Tue Jun 15, 2021 3:00 pm A substantial amount of the mileage in the New Jersey section of the Amtrak (PRR) mainline has the Amtrak 132kV single phase transmission lines, and above that, electric utility transmission overbuild (PSE&G 230kV) on the catenary poles. That extra railroad and public utility transmission greatly increases the complexity and cost of replacement.
The electric utility company should pitch in as well, it is their 132kV transmission poles that are rusting away too.
  by west point
 
David exactly my thought. The original PRR poles go into the ground where the bottom is rusting. The replacement is costing much more than anticipated and much slower to install..
  by photobug56
 
We just have to get PRR and hmm, what was the electric utility back then? Now PSEG is it now, at least for part of the state, but judging by their rep on Long Island (at least according to Long Island Power Authority)... Just curious - what is the obligation of the electric utility here?
  by Ken W2KB
 
electricron wrote: Tue Jun 15, 2021 6:03 pm
Ken W2KB wrote: Tue Jun 15, 2021 3:00 pm A substantial amount of the mileage in the New Jersey section of the Amtrak (PRR) mainline has the Amtrak 132kV single phase transmission lines, and above that, electric utility transmission overbuild (PSE&G 230kV) on the catenary poles. That extra railroad and public utility transmission greatly increases the complexity and cost of replacement.
The electric utility company should pitch in as well, it is their 132kV transmission poles that are rusting away too.
Amtrak owns the poles, and leases the right to place utility-owned conductors on them. Amtrak, as is any landlord, is obligated to maintain the leased premises and infrastructure unless specific language in a lease specifies otherwise. It is my recollection that the Amtrak lease contains no such language. Note that Amtrak derives significant income from such leasing and licensing agreements.
  by Ken W2KB
 
photobug56 wrote: Wed Jun 16, 2021 12:50 am We just have to get PRR and hmm, what was the electric utility back then? Now PSEG is it now, at least for part of the state, but judging by their rep on Long Island (at least according to Long Island Power Authority)... Just curious - what is the obligation of the electric utility here?
Brief history to date: The Public Service Corporation of New Jersey ("PSCNJ") was formed in 1903 and acquired hundreds of railway, manufactured gas, and electric companies in New Jersey. (The majority of the PSCNJ electric business grew out of the electric railway business.) The order of size and importance of the businesses in 1903 was railway, gas and electric. PSCNJ was dissolved in 1948 and PSE&G absorbed all three businesses. The present NJ utility is Public Service Electric and Gas Company ("PSE&G"), which was incorporated in 1924 by PSCNJ, and with whom the PRR contracted for the overbuild, as well as the Metuchen, NJ 25MW rotary frequency converter, still in operation converting 60Kz to 25Hz power for PRR now Amtrak on a load following and scheduled basis. The entire Amtrak (ex-PRR) line in New Jersey is located within PSE&G electric service territory. Amtrak inherited the contract from the PRR, and it does provide significant lease/license revenue to Amtrak. PSEG Long Island does not own any infrastructure. The Long Island Power Authority ("LIPA") owns all the infrastructure and entered into an Operations & Services Agreement on December 28, 2011 with Public Service Enterprise Group, Inc.(PSEG), the parent holding company, incorporated in 1985, of PSE&G and other businesses. The then in 2011 newly-formed for that purpose PSEG Long Island company, the winning competitive bidder to manage the operations of LIPA’s electric transmission and distribution system, commenced operations on January 1, 2014. That contract expires on December 31, 2025 and pursuant to another public bidding, the contract thereafter will be awarded to a winning bidder, which may or may not be PSEG. My recollection of my read of the PRR/Amtrak contract is that the Amtrak/PRR is solely responsible for maintaining the supporting poles and PSE&G is solely responsible for maintaining the PSE&G attachments to those poles, i.e., the arms attached to the poles to hold insulators and conductors. Thus, it is Amtrak's responsibility at Amtrak's expense to maintain the poles.
  by Ken W2KB
 
David Benton wrote: Wed Jun 16, 2021 12:34 am Hopefully they have earth straps to an independent earth rod. Otherwise the induced voltage in them would be high , let alone any leakage that may occur.
Absolutely. A couple or so decades ago a thief entered into an unmanned electric utility substation property, and commenced to cut the heavy copper braided grounding straps extending from the A-frame structure posts embedded in concrete foundation posts to the station's earth ground grid, to sell as scrap metal. Without need for involving the US criminal justice system, the thief suffered the death penalty when he removed the last grounding strap from the supports. I filed a copy of the utility's investigation with police report attached with the state utility commission as part of my regular job duties.
  by photobug56
 
Ken W2KB wrote: Wed Jun 16, 2021 10:54 am [...]
Thanks for the detailed history and explanation. All jokes aside, helps to understand the situation. Clearly Amtrak has a lot to get done in NJ.
Last edited by nomis on Thu Jun 17, 2021 11:03 pm, edited 1 time in total. Reason: truncated quote
  by hxa
 
Arlington wrote: Fri Jun 04, 2021 1:30 pm I read recently that the new CT catenary in NJ still had “leftover” elements that made it less global standard than TCCI and RI/MA are
I don't know what you are referring to. Anyway, there's indeed a significant difference between the "global standard" and what've been implemented in NJ: The new catenary system in NJ makes use of the "compound catenary" design, in which an additional wire is placed in between, and connected to the contact wire and the messenger wire. Compound catenary systems were quite common on Shinkansen lines built before 1990s. They carry more electric current, and are more even in elasticity, than simple cantenary systems, but are more costly to maintain. Given that NEC tracks south of NYC are electrificated at 12kV/25Hz, rather than +/-25kV/60Hz (under the same horsepower the engine would draw a 4x larger electric current from the catenary system on NEC south tracks), this non-standard catenary design has some sort of advantage over standard ones.
  by hxa
 
Fan Railer wrote: Mon Jun 14, 2021 10:26 am
photobug56 wrote: Thu Jun 03, 2021 7:17 pm I do admit to being very puzzled. All this testing on the NE corridor with one of the 2 test trains, not a single hint of problems during the testing. One would think that if problems were found, that adjustments, fixes would have been made even if the set had to go to a yard or the factory for a month, then resume testing, but we never heard of that happening.
As test speeds gradually climbed higher from the 90 mph mark, the aforementioned issues with the pantographs was discovered (excessive pan bounce when operating in the rear-pan-up configuration, which is supposed to be the normal operating configuration)...
Under such a configuration, the wind blowing from the front would reduce the force applied to the contact wire (amount of which increases with speed), making pantographs more easy to come off-wire under higher speeds.
The mod applied to the pan consists of two small spoiler fins designed to induce lift (like a plane wing) at the higher speeds, which keeps the pan in contact with the wire more consistently when it encounters areas of poor wire geometry which induce oscillation in the pantograph height.
This "genius" solution was originally proposed by engineers from British Rail and Brecknell, Willis & Co. in roughly 1970s. These fins induce a second counter force that also grows with speed, effectively making the pantograph applying an almost constant, speed-independent force to the catenary. Every single pantograph designed for high-speed operations in UK or US has adopted this design since then, except for the (original) ones on the new Acela.
  by rohr turbo
 
hxa wrote: Thu Jun 17, 2021 12:31 pm ...Given that NEC tracks south of NYC are electrificated at 12kV/25Hz, rather than +/-25kV/60Hz (under the same horsepower the engine would draw a 4x larger electric current from the catenary system on NEC south tracks)
Not to quibble, but wouldn't 12 kV draw approx. 2x the current for the same power delivered? The ohmic losses in the catenary would indeed be 4x (P=I^2R).
  by hxa
 
rohr turbo wrote: Thu Jun 17, 2021 1:37 pm
hxa wrote: Thu Jun 17, 2021 12:31 pm ...Given that NEC tracks south of NYC are electrificated at 12kV/25Hz, rather than +/-25kV/60Hz (under the same horsepower the engine would draw a 4x larger electric current from the catenary system on NEC south tracks)
Not to quibble, but wouldn't 12 kV draw approx. 2x the current for the same power delivered? The ohmic losses in the catenary would indeed be 4x (P=I^2R).
Good question. The factor 4 comes from the fact that auto-transformers are used under +/-25kV electrification, which redistribute electric current in the running rails to a positive feeder wire. The voltage between the feeder wire and the contact wire is 50kV rather than 25kV.
  by electricron
 
15kV 25 Hz impedance (Z) and 25kV 60 Hz impedance are not the same.
XL = 2π * f * L
Where XL is the inductive impedance, f is the frequency in Hertz and L is the inductance in Henrys.

If the only variable is frequency, the impedance of a circuit as 60 Hz is more than twice that at 25 Hz. But frequency is not the only variable because a different inductor (L) and its value would also change.

As for the 25kV turning into 50 kV using the auto transformer, likewise the 15 kV turns into 30 kV.
For both the reasons listed in this response earlier, the current draw at 60 Hz is not automatically four times as at 25 Hz. Resistance of the catenary and capacitance between the catenaries and ground change the overall impedance of the circuits, without specific details of their values it makes calculating practically impossible.
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