North East Corridor (NEC) speeds, new stations and state of repair

BlackDiamond said:

I assume by "NJT is all 60 Hz" you mean lines that are exclusively NJT such as the former Lackawanna out of Hoboken.

There is really no reason to convert from 25 Hz to 60 Hz and such a change would require a massive replacement of fairly modern solid state frequency converter substations plus the Susquehanna River dam generators that provide 25 Hz directly. Consider that in Europe Germany and Switzerland (and Austria?) still use 16.7 Hz and have no plans to convert from the lower frequency.

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There are plenty of reasons to convert the remainder of the system from 25 to 60 Hz. Interoperability with equipment designed for the 60-Hz systems that exist everywhere in the country except a portion of the NEC, simplified specs for future orders of locomotives / trainsets, ability to use power from the grid without frequency converters, etc.

Maybe those reasons justify the cost, maybe they don't, but there definitely are reasons.

Anyone know why the PRR decided to go with the lower frequency in the first place? Surely even by the 1930s 60-Hz power was becoming standard. Lower reactive losses? The pantograph skipping off the wire at frequencies near 60 Hz?

b1xn00d said:

Anyone know why the PRR decided to go with the lower frequency in the first place? Surely even by the 1930s 60-Hz power was becoming standard. Lower reactive losses? The pantograph skipping off the wire at frequencies near 60 Hz?

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I strongly recommend that you ask Google "Why did PRR use 25Hz for electrification?" and tell us what you find. I suspect you will find the answer to your question and learn quite a bit more to start asking more interesting questions on the subject

For reference just click on the following link:

https://www.google.com/search?q=Why+did+PRR+use+25Hz+for+electrification

b1xn00d said:

There are plenty of reasons to convert the remainder of the system from 25 to 60 Hz. Interoperability with equipment designed for the 60-Hz systems that exist everywhere in the country except a portion of the NEC, simplified specs for future orders of locomotives / trainsets, ability to use power from the grid without frequency converters, etc.

Maybe those reasons justify the cost, maybe they don't, but there definitely are reasons.

Anyone know why the PRR decided to go with the lower frequency in the first place? Surely even by the 1930s 60-Hz power was becoming standard. Lower reactive losses? The pantograph skipping off the wire at frequencies near 60 Hz?

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I agree that all things being equal, having a common 60 hz frequency would be better. However considering all that is needed in the Corridor for SOGR I think that is a lower priority than for example constant tension catenary so trains aren't pulling the wires down on hot days.

They are going to install over-sliding 3rd rail up the Hell Gate line into western Wooside about a mile and a half up from Harold, so that takes care of the commonality need for MN MU trains to Penn Station. NJT Arrow MU's will be gone in 2 or 3 years. Everything else can convert on the fly. SEPTA is in no financial shape nor has the need to convert their own Pennsy and Reading branches to 60Hz.

Amtrak25 said:

They are going to install over-sliding 3rd rail up the Hell Gate line into western Wooside about a mile and a half up from Harold, so that takes care of the commonality need for MN MU trains to Penn Station. NJT Arrow MU's will be gone in 2 or 3 years. Everything else can convert on the fly. SEPTA is in no financial shape nor has the need to convert their own Pennsy and Reading branches to 60Hz.

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I don’t understand the MN MU comment. The M8’s have pantographs and operate on overhead wire for most of their journeys today. Why would they need to add third rail for them?

Forgive me, but I really don’t get the interest with this proposed project. Conversion to 60HZ seems that it would save a small amount on future rolling stock purchases, but if I’m understanding rightly, it would have little impact on reliability and operating expenses, cause difficulty for commuter roads, and require significant capital expenditure. Wouldn’t it be better to just accept we have a legacy system, and move forward with more pressing issues?

There are some locations mainly in coal country that still use 25 hZ. That is slowly being reduced.

blueman271 said:

I don’t understand the MN MU comment. The M8’s have pantographs and operate on overhead wire for most of their journeys today. Why would they need to add third rail for them?

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M8s cannot operate under 25Hz. It is 60Hz upto CP Gate. From there on it is 25Hz into Penn Station. M8s will operate on DC from Third Rail in 25Hz territory.

jis said:

M8s cannot operate under 25Hz. It is 60Hz upto CP Gate. From there on it is 25Hz into Penn Station. M8s will operate on DC from Third Rail in 25Hz territory.

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If M-8's had the heavy transformers to handle the 25Hz, it would have put the cars over 80 tons. Not worth it for the handful to operate in this service.

M-8's assigned to ShorelIne East service (12 of the Connecticut-owned ones) had their 3rd rail shoes removed since they could have been torn off by bridge structures east of New Haven.

There is no such thing as a universal MU.

Septa9739 said:

Forgive me, but I really don’t get the interest with this proposed project. Conversion to 60HZ seems that it would save a small amount on future rolling stock purchases, but if I’m understanding rightly, it would have little impact on reliability and operating expenses, cause difficulty for commuter roads, and require significant capital expenditure. Wouldn’t it be better to just accept we have a legacy system, and move forward with more pressing issues?

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Europe is littered with both 50 Hz and 16 2/3 Hz train lines. If they don't feel obligated over there to unify under the grid standard 50 Hz, I doubt there's a justification or compelling reason to do so here either. It's still a hurdle, but it's pretty low.

There is an infatuation, among the "content mills" in particular, with identifying this as a huge problem because it is in fact a relic of being "old" but that doesn't automatically make it a problem. The difficulty in procuring parts is a problem, though.

Besides that, I think Amtrak's 25 Hz system is actually especially resilient because of its ability to run with several converters offline combined with its near-total continuity of highly redundant long distance transmission lines. As far as I know, typical new-build 25kV/50kV autotransformer systems as seen here in the US and around the world can have a localized outage when a single provider at a single substation fails. I haven't heard of the underlying transmission system system failing any time recently, but I have heard of utility provider failures on Amtrak's and NJ Transit's 60 Hz systems. Amtrak's system covers over 200 miles of rail and doesn't depend on a single utility connection.

How We Get Around made a "response" video to Half as Interesting's low quality video on NEC south-end electrification:


Note: Safe Harbor is not the sole source of Amtrak's 25 Hz power but it's the only connection/generation that isn't first converted from the grid 60 Hz: it's straight from hydroelectric turbine to 25 Hz power. (Safe Harbor has two turbines but also has a motor-generator)