ACS-64 Heads Up

[jis]

I'm gunna sound a bit stupid but, what exactly is "IGBT power"?? I really don't understand what it is.. TIA.

First of all let me assure you there is no question that is stupid. Asking a question is an admirable quality indicating that one is aware of ones limits of knowledge and is willing to learn.
IGBT (Insulated Gate Bipolar Transistor) is a type of electronic device which can switch the flow of electricity off and on at controlled variable rates. This property together with some additional circuitry makes them highly suitable for use in Inverters that are used to produce AC from DC at variable frequency that can be controlled precisely. They can also handle quite large currents (up to ~1,000Amp) at many thousand volts, thus making them suitable for use in power electronics that is used in the drive systems for AC motors in modern electric engines.

In modern engines the power that is drawn from the catenary is first converted to DC at a suitable intermediate voltage, something around 3,000v which drives a common DC link bus. Then all the power consumers feed off of this bus through inverters to deliver the right form of AC for each specific use. This is what makes versatile power inverters that are compact very important, and IGBT is the enabling technology for such. Of course one of the major consumers are the traction motors that provide the motive power for the engine to move a train (and itself).

A typical module capable of handling over a thousand Amps of current at upto 3300V looks like this:

This particular one is a Mitsubishi module. But there are similar modules in the ACS-64 for driving each traction motor.

As it turns out, even though HEP requires a constant frequency AC, the inverter that is used for HEP is essentially the same as a traction inverter but in the HEP mode of operation is controlled differently. The reason this is done is that in case of a traction inverter failure, the HEP one can be used as replacement and conversely in case of a HEP inverter failure a traction inverter can be used as substitute. The latter of course reduces the traction power output of the engine, but that may be tolerable in many cases in order to keep the passengers from freezing or getting a heat stroke.

You can read up more about it starting from the Wiki article on IGBT which can be found at http://en.wikipedia.org/wiki/Insulated-gate_bipolar_transistor.

Hope that helps clarify more than further confuse.

 

[jis]

George, is there a way to spray sand on the tracks to increase traction? It sounds stupid but I thought that there was a way old Great Northern locomotives could do that, but in retrospect, it sounds odd.

On edit: Google is your friend, Ziv. So they do have sand sprayers on most locos. Will the ACS-64 use sand in rainy conditions when the rail is slick to keep their acceleration close to normal? How often do locos use sand to improve traction? I would like to see it done, or rather, perhaps, hear it done.

They use it whenever necessary.
However, no amount of sand is going to change the basic rail to wheel coefficient of friction by much, and that is what keeps the trains moving. Sand alleviates the reduction in that coefficient due to icing or leaf oil on the rail etc. Other techniques used to mitigate such problems is track washing, applying deicing fluid to rails etc. And engines like the ACS-64 have extremely sophisticated slip control mechanisms built in which enable the engine to run at the edge of traction, which is the most efficient place to be at and provides the most traction. But it can never be more than that governed by the weight on the wheel and the coefficient of friction.

 

[Fan Railer]

George, is there a way to spray sand on the tracks to increase traction? It sounds stupid but I thought that there was a way old Great Northern locomotives could do that, but in retrospect, it sounds odd.

On edit: Google is your friend, Ziv. So they do have sand sprayers on most locos. Will the ACS-64 use sand in rainy conditions when the rail is slick to keep their acceleration close to normal? How often do locos use sand to improve traction? I would like to see it done, or rather, perhaps, hear it done.

At the end of this video I shot at Metropark, if you listen closely enough,the engineer turns the sander on so the ALP-46 can shove its heavy consist out of the station. Metropark is great if you want sanding action:

Start watching at 16:50, and make sure it's in HD.

 

[ACS-64]

600 said to be on the expected 152/159 rotation today.

 

[Ziv]

jis, Fan Railer, thank you both very much for your responses. I just remembered something about the sand traction application from when I was a kid and it is cool to find out I hadn't completely mis-remembered it!

 

[Acela150]

I'm gunna sound a bit stupid but, what exactly is "IGBT power"?? I really don't understand what it is.. TIA.

First of all let me assure you there is no question that is stupid. Asking a question is an admirable quality indicating that one is aware of ones limits of knowledge and is willing to learn.
IGBT (Insulated Gate Bipolar Transistor) is a type of electronic device which can switch the flow of electricity off and on at controlled variable rates. This property together with some additional circuitry makes them highly suitable for use in Inverters that are used to produce AC from DC at variable frequency that can be controlled precisely. They can also handle quite large currents (up to ~1,000Amp) at many thousand volts, thus making them suitable for use in power electronics that is used in the drive systems for AC motors in modern electric engines.

In modern engines the power that is drawn from the catenary is first converted to DC at a suitable intermediate voltage, something around 3,000v which drives a common DC link bus. Then all the power consumers feed off of this bus through inverters to deliver the right form of AC for each specific use. This is what makes versatile power inverters that are compact very important, and IGBT is the enabling technology for such. Of course one of the major consumers are the traction motors that provide the motive power for the engine to move a train (and itself).

A typical module capable of handling over a thousand Amps of current at upto 3300V looks like this:

This particular one is a Mitsubishi module. But there are similar modules in the ACS-64 for driving each traction motor.

As it turns out, even though HEP requires a constant frequency AC, the inverter that is used for HEP is essentially the same as a traction inverter but in the HEP mode of operation is controlled differently. The reason this is done is that in case of a traction inverter failure, the HEP one can be used as replacement and conversely in case of a HEP inverter failure a traction inverter can be used as substitute. The latter of course reduces the traction power output of the engine, but that may be tolerable in many cases in order to keep the passengers from freezing or getting a heat stroke.

You can read up more about it starting from the Wiki article on IGBT which can be found at http://en.wikipedia.org/wiki/Insulated-gate_bipolar_transistor.

Hope that helps clarify more than further confuse.

Thanks for that Jis! It's all a lot clearer now to me.

 

[jis]

#601 will be commissioned tomorrow (Feb 18) with a special train run from WAS to BOS leaving WAS at 8:15am. It will run on a returns special train out of BOS on the 19th at 9:15am all the way to DC. Then it will enter regular service on the 20th.

 

[Acela150]

Jis will 601 run between 2155 and 93 or will it run before the 2?

 

[Guest]

Just saw an ACS64 heading North out of 30th Street Station(Philly). It was only pulling 4 cars. Could this be the special run with 601 in the lead?

 

[jis]

Just saw an ACS64 heading North out of 30th Street Station(Philly). It was only pulling 4 cars. Could this be the special run with 601 in the lead?

Sounds about right, since it is supposed to have departed Washington DC at 8:15am.

 

[Fan Railer]

Word is she departed Washington about 25 min late at 8:40.

 

[Acela150]

605 is sitting in Sunneyside and 606 is at New haven this morning.

Sent from my iPhone using Amtrak Forum

 

[bgiaquin]

607, 608, & 609 are at Siemens ready for delivery. One could be out East by the end of February, but based on the 3 per month delivery schedule, I assume these 3 may be delivered in early, mid and late March, respectively.

 

[Ryan]

If they're all ready to go, why not deliver them at the same time?

 

[bgiaquin]

If they're all ready to go, why not deliver them at the same time?

That would make the most sense. There is some reason as to why one at a time but I do not remember what it is.

 

[Nathanael]

If they're all ready to go, why not deliver them at the same time?

That would make the most sense. There is some reason as to why one at a time but I do not remember what it is.

I'd love to know too. I understand the reason for not delivering, say, two dozen at a time (a heavy and yet delicate load for the train shipping them), but in the transit world it's fairly common to deliver up to 4 EMUs in one shipment, so I don't quite see why you wouldn't ship 2 or 3 locomotives at once. Are they so heavy that the hauling locomotive has trouble handling more than one?

 

[Tracktwentynine]

If they're all ready to go, why not deliver them at the same time?

That would make the most sense. There is some reason as to why one at a time but I do not remember what it is.

I'd love to know too. I understand the reason for not delivering, say, two dozen at a time (a heavy and yet delicate load for the train shipping them), but in the transit world it's fairly common to deliver up to 4 EMUs in one shipment, so I don't quite see why you wouldn't ship 2 or 3 locomotives at once. Are they so heavy that the hauling locomotive has trouble handling more than one?

Let's think about this logically.

Amtrak can only test new ACS64s at a certain rate. Probably with just 1 or 2 going through acceptance on the corridor at any given time. Regardless of how many are at Wilmington, they can only run a few test trains/crews.

So if Siemens delivers them faster than planned, they'll just sit at Wilmington (rather than Sacramento). No big problem.

Now, I know we're all railfans here, and we WANT MOAR LOCOS NOW!, which is all well and good. But just because we want the locomotives to be in Delaware rather than California doesn't mean it makes sense to do so.

Amtrak already has 6 on the East Coast, and has 2 in service (#600 and #601). The other 4 are being tested and accepted.

So, let's say Amtrak wanted to bring all 3 at once.

Normally the ACS is attached to the California Zephyr (and Capitol Limited). That works fine with 1 loco. 2 might be too heavy (remember, it's not adding any tractive power, just dead weight). 3 might make the train too long for platforms in addition to being too heavy.

So bringing all 3 at once would probably mean chartering a special train or having these added to a freight (at some expense to Amtrak).

So basically, Amtrak can spend a bunch of money getting all 3 at once (so all 3 can sit in a rail yard) or it can pay a very small additional amount of fuel and deliver each one on 3 consecutive Zephyrs.

It's basically the same reason you don't get 3 months of groceries on one trip. Getting the locos to Wilmington sooner isn't going to get them accepted any sooner. And it will cost Amtrak a lot more, so why not just bring the three separately?

 

[bgiaquin]

If they're all ready to go, why not deliver them at the same time?

That would make the most sense. There is some reason as to why one at a time but I do not remember what it is.

I'd love to know too. I understand the reason for not delivering, say, two dozen at a time (a heavy and yet delicate load for the train shipping them), but in the transit world it's fairly common to deliver up to 4 EMUs in one shipment, so I don't quite see why you wouldn't ship 2 or 3 locomotives at once. Are they so heavy that the hauling locomotive has trouble handling more than one?

Let's think about this logically.

Amtrak can only test new ACS64s at a certain rate. Probably with just 1 or 2 going through acceptance on the corridor at any given time. Regardless of how many are at Wilmington, they can only run a few test trains/crews.

So if Siemens delivers them faster than planned, they'll just sit at Wilmington (rather than Sacramento). No big problem.

Now, I know we're all railfans here, and we WANT MOAR LOCOS NOW!, which is all well and good. But just because we want the locomotives to be in Delaware rather than California doesn't mean it makes sense to do so.

Amtrak already has 6 on the East Coast, and has 2 in service (#600 and #601). The other 4 are being tested and accepted.

So, let's say Amtrak wanted to bring all 3 at once.

Normally the ACS is attached to the California Zephyr (and Capitol Limited). That works fine with 1 loco. 2 might be too heavy (remember, it's not adding any tractive power, just dead weight). 3 might make the train too long for platforms in addition to being too heavy.

So bringing all 3 at once would probably mean chartering a special train or having these added to a freight (at some expense to Amtrak).

So basically, Amtrak can spend a bunch of money getting all 3 at once (so all 3 can sit in a rail yard) or it can pay a very small additional amount of fuel and deliver each one on 3 consecutive Zephyrs.

It's basically the same reason you don't get 3 months of groceries on one trip. Getting the locos to Wilmington sooner isn't going to get them accepted any sooner. And it will cost Amtrak a lot more, so why not just bring the three separately?

Just to clarify, Amtrak has 7 units on the east coast, 600-606.

 

[Ryan]

I wasn't necessarily meaning at the exact same time, and once things settle into a routine I can see them being sent east as they're ready one every 10 days or so.

But since they're sitting there ready to roll, no reason to spread them out over the month, send them 3 consecutive days, or during the same week, unless bgiaquin has some inside info that they are going to be spread out.

 

[NE933]

Spreading out deliveries is also for insurance, to spread out risk. If a train with three ACS-64 derails that's gonna put a dent in things, which we don't need.

 

[bgiaquin]

I wasn't necessarily meaning at the exact same time, and once things settle into a routine I can see them being sent east as they're ready one every 10 days or so.

But since they're sitting there ready to roll, no reason to spread them out over the month, send them 3 consecutive days, or during the same week, unless bgiaquin has some inside info that they are going to be spread out.

Nope, no inside info for me. I was just making a guess. They may send them out 3 days in a row or 3 weeks in a row. We have to wait and see. I was putting that out there as a "maybe x, y, and z".

 

[ACS-64]

Any word if 601 entered revenue service today? If so what trains?

600 was on the usual 184/129 turn.

 

[afigg]

So, let's say Amtrak wanted to bring all 3 at once.

Normally the ACS is attached to the California Zephyr (and Capitol Limited). That works fine with 1 loco. 2 might be too heavy (remember, it's not adding any tractive power, just dead weight). 3 might make the train too long for platforms in addition to being too heavy.

So bringing all 3 at once would probably mean chartering a special train or having these added to a freight (at some expense to Amtrak).

So basically, Amtrak can spend a bunch of money getting all 3 at once (so all 3 can sit in a rail yard) or it can pay a very small additional amount of fuel and deliver each one on 3 consecutive Zephyrs.

It's basically the same reason you don't get 3 months of groceries on one trip. Getting the locos to Wilmington sooner isn't going to get them accepted any sooner. And it will cost Amtrak a lot more, so why not just bring the three separately?

Remember, the earlier ACS-64s were delivered sandwiched between two P-42s all the way to WAS. So the consists were extended by 3 locomotives, but the platform length is not relevant because the lead locomotive(s) don't need to access the platform.
Perhaps Amtrak will sandwich two ACS-64s between two P-42s to get 2 units to the east coast at once to catch up on the delivery schedule. However, the past 5-6 weeks have been brutal on the P-42 fleet with many units reportedly out for repair, so it is possible that Amtrak is tight on available diesel locos to bring the ACS-64s east. We will see what happens over the next few weeks.

Amtrak has good reasons to get the new ACS-64s to the east coast and through the check-out process to get them into service. The sooner they can get a batch of ACS-64s in revenue service, the sooner they can retire the most troublesome and least reliable AEM-7DC and HHP-8 units.

 

[jis]

Remember, the earlier ACS-64s were delivered sandwiched between two P-42s all the way to WAS. So the consists were extended by 3 locomotives, but the platform length is not relevant because the lead locomotive(s) don't need to access the platform.

I do not think that was the case in general. Don't know about the others, but the first one was delivered by Capitol Ltd. sandwiched between two of its regular P42s. So the consist had only one extra unit and that was the ACS-64. I know because I was on that train traveling SOB to WAS. Saw the train roll into SOB with the ACS-64 between the two P42s.
In general I don't think they need any additional diesel locos to ferry ACS-64s. There was one that had its own pair because it had to be taken to Hornell, and it traveled by the LSL to Albany and thence to Hornell. I saw that operation too since I happened to be in Albany the day it arrived there. The next day and Empire Service train brought the two diesels back to Albany, and then they headed back to Chicago via LSL as far as I recall.

 

[Fan Railer]

601 did not enter service today.