Randy, none of the GG1s should not have transformers any longer. All were removed as far as I am aware.

So lets approach the GG1 from an electrical engineering standpoint. The input is 11,000 VAC 25 cycles. The question that needs answered is what is the operating voltage of the traction motors and how was speed controlled? I have never found any explanation as to what kind of AC traction motors are on the G. Usually AC motors cannot vary their speed as it is pegged to the frequency unless it is a universal motor. Now if they are universal motors then they CAN run on direct current.

So what if instead of having a transformer with multiple taps, a transformer with one tap was used but teamed up with a variable frequency drive to control speed. Lets say we use a transformer that went from 11,000 VAC to 480 VAC (should be available off the shelf) then using a series of VFDs we could then control the speed of the motors. The fact that the GG1 was designed for 25 cycles should not matter in this case since we could just limit the VFD to a range between 0 and 25 hertz, or determine what the upper tolerance the motors could handle and adjust the VFD accordingly.

We need more electrical specs on the GG1 to take this thought exercise further.

Folks,
As Al mentioned up above; we do have freight motors at the Western Railway Museum. I have done cab rides in the SN #654 with an SN caboose full of kids in tow.

We have also pulled passenger cars with our Key System #1001 a home, 600-volt built steeple cab freight locomotive.

Some folks would like to put a set of batteries into our Brigham Copper mine steeple cab. It ran on 750 overhead or 600-volt batteries.

I would love to see an Amtrak AEM-1 locomotive run again. I do not believe it has any nasty chemicals in it!

Ted Miles

In all of this blather, no one has reminded all what REALLY retired the PRR/Amtrak/NJT GG1s: Frame cracks.

Might not matter if you're only rolling at 5 MPH on a museum spur. But there will inevitably be calls to get her movin' with a big train.........

So, what else ya got?

I believe a few individuals covered the topic of frame cracks, including the fellow from the CNR 6167 group. There are methods of welding and heating the locomotive frames. I'm no expert, but with 21st Century technology, a GG1 restoration is much less far-fetched than the idea of the T1 trust succeeding... Not to say the 5550 group won't succeed, but a GG1 running in the future is more possible than ever. As many have said in the past, technically speaking transformers and switchgear from ASEA/EMD AEM-7's (which Amtrak has a large surplus of at this time) could be retrofitted into the space that a G's transformers and such used to occupy. As they say, anything is possible with a blank check. If it had come down to a matter of searching for other parts, such as running gear, 16 "survivors" (if you can even call them all that) reside in various states of disrepair and could be possible donors.

Now finding ANY mainline capable of handling all 475,000 pounds of a GG1 with catenary would be a feat.

Maybe we can persuade NS to re-electrify Enola and reopen the Enola Low Grade line ;) (Tongue in cheek of course, before the enormous amounts of backlash from keyboard warriors come in).

Rick, the GG1's had single-phase series wound induction motor. Essentially, it was the predecessor to the universal motor. Nonetheless, it is not frequency dependent hence the taps on the transformer. Essentially the different notches on the throttle (taps on the transformer) are controlling the current being pushed through the motor.

Higher current = stronger magnetic field = more HP

25Hz transformers aren't that hard to come by (Amtrak gets them) and they are much more efficient than the transformers that were originally installed in the GG1's over 80 years ago.

In my opinion, a GG1 would be much easier to restore than a steam locomotive. (As much as I love steam locomotives, they are essentially a pressure-vessel on wheels). Electric locomotives do not have as many moving components.

In terms of providing HEP to rest of the train-set. A frequency converter would probably fit where the old boiler was and could be tapped off the main transformer.



Yes, the cracks contributed to the GG1's being retired, but you have to remember, most of these cracks appears after 40 years of service. By that point, it was a better investment for the owners to upgrade to a newer locomotive rather than repair a 40 year old piece of technology. Think about how far the electrical components inside had come in those 40 years. They were probably starting to have trouble locating new parts for the inners of the GG1s when they wore out at that point. Part of engineering is practicality (and cost efficiency): from a practical standpoint it makes sense to upgrade over repair past a certain age. Same thing anyone would do when repairs to their automobile gets too pricey: trade it in rather than pouring money into an older vehicle.

Now, I don't know much about cracks in locomotive frames so I can't answer whether it can be fixed or not. A master welder is typically able to do a weld that is as strong as the original material so I don't think this is as big as an issue as it seems (still depends on location of crack and distribution of the weight across the frame on the feasibility of getting it fixed).

I hope this answered any engineering questions that were left unanswered.

1) Yes
2) No. My impression is that the 803 puts much less of a strain on the museum's substation than a five-car North Shore train or this monstrosity. Earlier in this thread it was suggested that IRM has two substations (correct) with one as a backup for the other (incorrect). One substation powers the main campus and the west end of the main line, while the other powers the eastern ~4 miles of the main line.

A non-profit isn't actually a bad idea if people are serious about seeing a GG1 roll under it's own power again.

I would be down to co-start a non-profit to at least investigate the possibility of seeing this happen... a feasibility study (99% of all engineering and any other business ventures start with a feasibility study) compared to feasibility speculation.

As I see it the goal of this study would be to answer the following questions:

1. Would an owner of one of the surviving GG1's be willing to let it be restored to operating condition if we have a place to run it? (No matter of what modifications that needed to be made to the "guts" of the engine.

2. Who would let us operate it on their track/catenary? (I see West Chester RR as a prime place if we can re-string some wire).

3. Can we gather enough interest and support (enough people to pledge) to get the ball rolling? The more promising a project looks, the more likely people are to donate. The T1 trust does a great job in both gathering support and fundraising - it would be prudent to 'take a page out of their book'. If we're going to do it, then we would have to do it the right way.

At the end of the day, if the answer to those questions are less-than-desirable, then game over and we're left with a few bruised ego's and some lost time. But, at least we would know for sure.

Well, this is partially correct;



Correct.



Also correct.



Additionally; Higher current = stronger magnetic field = more HP = higher speed



Mostly Not True, the efficiency of an electric transformer is determined by the material properties of the components (reluctance of the field/stator components, resistance of the wiring (mostly copper)) and the BIG PLAYER is the frequency...

The Airplane Industry changed over to 400 "cycle" = 400 Hertz well over 50 years ago. because they could get "about" the same efficiency of voltage transformation though a much smaller (and lower weight) transformer than a 60 Hertz system.

I seriously doubt that Amtrak has changed the fundamental physics of transformer construction in 80 years.

I would wager that the electrical efficiency of Amtrak's "modern" 25 Hz transformers is not more than 10% better than the "old" PRR 25 Hz transformer. A little better control of stray eddy currents with modern CAD design tools and better control of leakage currents with modern insulators.

However, with modern CAD tools and much better materials (Plastics) a modern 25 Hz transformer could be a little bit smaller than a "PRR era" 25 Hz transformer. Back in the old days if you tested something 1 inch thick and it passed the test (strength or voltage) you would "play it safe" and specify a 2 inch thick part to make sure it did not fail. Now, with better CAD tools and materials what used to be a 2" thick part may only need to be 1/4" thick to operate safely.

'Lectricity, everybody's been studying it for years, nobody knows how the heck it works...

Cheers, Kevin

GG1's have traction motors that can run on either low-frequency AC or DC. I think 25 Hz is the highest AC frequency. The Central Europeans use 16 2/3 Hz power and their AC locomotives seem to buzz and vibrate a lot less than GG1's. PRR never ran their AC motors on DC but NH did on NYC's underrunning third rail into GCT. [NH ran on AC on PRR which has overrunning third rail between "HAROLD" and Penn Station]

A GG1 weighs 460000 lbs on 20 wheels. Driving axle load is 50000 lbs. By contrast, an EMD SW1 weighs 200040 lbs on 8 wheels with an axle load of 50001 lbs. A GG1 should be able to go anywhere that has 12 kV 25 Hz AC wire.

Replacing the steam boiler with an HEP module is how Amtrak converted the steam E60CP's into HEP E60CH's.

Wilmington Shop was forever welding cracks in GG1 frames. They used their experience gained from welding cracks in P5a frames. Moreover, a GG1 did not enjoy running at speeds of 100 mph or over. Especially braking from 100 mph. When Amtrak wanted NEC trains to do 125 mph,they knew the GG1's needed replaced.

Swedish RC4 X995 tested in Metroliner service and did well. The AEM7 is based on the RC4 and could pull 7 Amfleets on a Metroliner schedule. A GG1 could lug 15+ standardweight cars up from under the Hudson River and then run 85-90 mph with them. Different times, different needs.

As to running a GG1 on a short line, PRR had electrified to West Chester, but would you want to run a GG1 without giving it a chance to stretch its legs?

Phil Mulligan

I’m sure one of the Cooperstown GG1s would work best here. They’re in pretty bad condition, which means that their owner might be alright parting with them, compared to, say, the RRMPA (who would never allow this).

So what's the point here again??

Is it really to operate a preserved electric locomotive (while preserving its historic fabric), or is to have a large toy train?

Because all this talk about altering an actual preserved locomotive to run it under modern conditions is just that.

Kevin,

I agree with you on all these comments.

I should have clarified more on this part of it, the increase in transformer efficiency is due to better dielectrics used as well as the potential to use better core materials.

I believe the dielectrics that are used now have a better dielectric constant and act as a better coolant than the PCB that was in there. (Depending on what core materials the original GE transformers had) using a high performance core material could lead to lower eddy currents.

On top of all this, manufacturing techniques for transformers have improved over time.

Likewise, I am hesitant to put a percentage on how much the efficiency has improved. I could see it being between 10% and 20%.

If you had read up, you would’ve seen what people were proposing. Swapping internal transformers and switch gear is not as far fetched as some of the other ideas given. I don’t quite understand your point, as we’ve done FAR much more work to steam locomotives. Hell, people are beginning to install PTC into steam. If that is somehow less work than what would be done to a GG1, Ive lost all faith in the world of preservation. Not saying it could/can/will be done, but you serve a moot point when saying “or is it to have a large toy train?” I could pose the same question to groups such as FWRHS, SRI, KSHCO, Friends of the 261 and more. There are even groups converting locomotives to burn oil over coal, or even biofuel like that one ATSF locomotive. You also seem to forget that a locomotive already HAS been greatly changed from its original fabric and yet it attracts millions annually (UP 4014). Operating a steam locomotive with modern regs is exactly the same as operating an electric in terms of historic fabric. Last I checked, every operable steam locomotive has had some amount of boiler and running gear work done. A GG1 would be different practice, yes, but the same idea.

> Because all this talk about altering an actual preserved locomotive to run it under modern conditions is just that.


Is it any different than replacing an original riveted boiler on a steam locomotive and replacing it with a new, modern, all welded boiler? In the case of a steam locomotive, in end all you did was strip off a significant chunk of its historic fabric just “to have a large toy train" to use your words. I really see no difference between replacing a boiler and replacing some portion of the electrical equipment within a GG1.

J.R.