ALP-45-DP Usage/Service Patterns

[baldwr]

The problem isnt' so much the roof line or where the pan sits when its lowered, but rather how close the pan is to the wire when its lowered. There isn't enough clearance to guarantee that you won't arc from the wire to the pan when its in its lowered position, thats why they don't want it dropped in Hoboken Terminal or any other low catenary clearance locations

JT - Thanks for the follow-up. I have been away from all of this for a bit. I understand the point that the clearances are tight within the station. The closer the wire is to the top of the pan is that much less distance you have when trying to break the circuit. If you do not get enough distance, the arc will last longer since the gap resistance is less. That can cause significant damage to electrical equipment (Catenary and / or pantograph). I would not expect the surrounding shrouding to play a role. The arch would travel to most direct path from the catenary to the top of the pantograph.

NS3010 mentioned a few posts back that special instruction requires the ALP46(A) to reverse its pantograph when ever it is going through a direction change:

What about electric locomotives that operate and turn in Hoboken? Per special instruction, electric locomotives must operate with the trailing pantograph up. Additionally, the SI on "Changing Pantographs" states that the engineer mush change pans when the direction of the locomotive will change (except when it will be moved into a yard) and "This applies to all locations including yards." No mention of an exception for the Hoboken trainshed

If the ALP-46's can switch pans in Hoboken, why is there that rule for the 45's? Is there a difference between the lowered pan heights of the 45's and 46's?

Following that, Dutch mentioned that, based on the stats, the 45's pantograph is 3 inches lower than the 46(A)'s:

height of ALP-46 is Height over pantographs 4 489 mm / 173.73”

http://www.br146.de/revisionen_daten/AL ... t08_en.pdf" onclick="window.open(this.href);return false;

Height of ALP45DP is Height over pantograph 14’ 41⁄8” / 4 400 mm

http://www.br146.de/revisionen_daten/Du ... t08_en.pdf" onclick="window.open(this.href);return false;

Making the ALP46/46a about 3 inches higher than the Dual power.

I know the simple answer is they do not allow the mode change. I apologize for the length and detail of the following questions. My intention is to better understand the operations - something I am not familiar with.

1) ALP-45 DP Mode Changes - When they switch modes with the 45-DP, it is always stationary so it should be drawing transformer magnetization, the HEP load and other "on board systems" - i.e. controls, blowers, etc.). When going from E-Mode to D-Mode, do they first shut down all HEP loads and then lower the pantograph prior to starting the gens (i.e open transition - break transfer); or are the gens started first and brought on in "parallel" (via the DC Bus I would assume) with the pantograph input, then the pantograph lowered (i.e closed transition - no break transfer)? Is there a circuit breaker between the pantograph and the transformer that is operated during the mode change (i.e opened when lowering, closed once raised), or is the pantograph treated like a giant air break switch (i.e the pantograph breaks the circuit)?

2) ALP-46(A) Operations in Hoboken Terminal - Do they do the panto switch in Hoboken Terminal with the ALP-46(A)s? If so, I do not see how the risk of an arc being any less with the 46(A)s vs. 45s. The 46's have 3 in less clearance - the main issue. Assuming that the direction switch is "Closed Transition" (i.e. raise the pantograph to be used then lower the other), an arc still could be drawn by the lowering pantograph since it is carrying some though not all current.

[Fan Railer]

I know the simple answer is they do not allow the mode change. I apologize for the length and detail of the following questions. My intention is to better understand the operations - something I am not familiar with.

1) ALP-45 DP Mode Changes - When they switch modes with the 45-DP, it is always stationary so it should be drawing transformer magnetization, the HEP load and other "on board systems" - i.e. controls, blowers, etc.). When going from E-Mode to D-Mode, do they first shut down all HEP loads and then lower the pantograph prior to starting the gens (i.e open transition - break transfer); or are the gens started first and brought on in "parallel" (via the DC Bus I would assume) with the pantograph input, then the pantograph lowered (i.e closed transition - no break transfer)? Is there a circuit breaker between the pantograph and the transformer that is operated during the mode change (i.e opened when lowering, closed once raised), or is the pantograph treated like a giant air break switch (i.e the pantograph breaks the circuit)?

2) ALP-46(A) Operations in Hoboken Terminal - Do they do the panto switch in Hoboken Terminal with the ALP-46(A)s? If so, I do not see how the risk of an arc being any less with the 46(A)s vs. 45s. The 46's have 3 in less clearance - the main issue. Assuming that the direction switch is "Closed Transition" (i.e. raise the pantograph to be used then lower the other), an arc still could be drawn by the lowering pantograph since it is carrying some though not all current.

1. The mode changes are made without breaks to HEP. As for your circuit question, there appear to be several circuit breakers in the ALP-45's electrical setup as seen in the two circuit diagrams here (I'm not indicating anything towards how they operate during mode changes): http://documents.epfl.ch/users/a/al/all ... ch1109.pdf" onclick="window.open(this.href);return false;

2. This was addressed a couple posts back, but to make it plain and simple, NJT could probably care less about arching on the ALP-46(A)s while switching pantographs because there are no diesel fumes to ignite. If you take this answer in context to the previous answer (that the pans are raised AND lowered during mode changes with the diesels on), then it makes more sense.

[DutchRailnut]

you and your diesel fumes, with engine running there would not be diesel fumes in fact exhaust has inert gas consistency.
as for tanks they are vented at track level.

[Fan Railer]

you and your diesel fumes, with engine running there would not be diesel fumes in fact exhaust has inert gas consistency.
as for tanks they are vented at track level.

Despite being relatively less flammable than regular gas engine exhaust, diesel exhaust is still flammable (http://safety.cat.com/cda/files/836622/ ... 1010.1.pdf" onclick="window.open(this.href);return false;). And judging by the way these locomotives idle while providing HEP lends to the fact that there is still plenty of exhaust that would be in the general area of a potential low clearance arching event. So I'm not really sure what kind of point you're trying to make here.

[DutchRailnut]

point is, there is no problem with diesel fumes, and never was, other than in your mind.
LIRR, MNCR and NJT run diesels under wire on daily basis and despite heavy arching on trains next to them never had any problems.

[Don31]

Despite being relatively less flammable than regular gas engine exhaust, diesel exhaust is still flammable (http://safety.cat.com/cda/files/836622/ ... 1010.1.pdf" onclick="window.open(this.href);return false;). And judging by the way these locomotives idle while providing HEP lends to the fact that there is still plenty of exhaust that would be in the general area of a potential low clearance arching event. So I'm not really sure what kind of point you're trying to make here.

I think you're confused. Diesel fumes are flammable, NOT diesel exhaust. Read the link you posted. Exhaust has already gone thru the combustion process, it can't burn a second time.....

[sixty-six]

you and your diesel fumes, with engine running there would not be diesel fumes in fact exhaust has inert gas consistency.
as for tanks they are vented at track level.

From what I understand, the 45's have no venting, which is why they can't be filled 100%. (Warning stickers by the fuel fillers state this). Also with the ALP46 pan change, from what I've been told (Jt I believe you told me this) both pans are live as long as one is up, so there's no arcing when changing pans.

[trollyFoamer]

Do they raise one pantograph, then lower the other? In that case there'd be no arc, which is not an option when moving an ALP-45-DP's single pantograph, even if it's the same height as other straight electric locomotives.

Maybe you heard it from the mouth of babes on the previous page. No, I will not provide photos to prove I'm a babe, I just mean I only have around 50 posts. Wadda ya godda do round here to get credubulity?

[DutchRailnut]

They have to have venting or you get imploding tank car type of behavior.
most likely the ALP45DP has multiple fuel tanks and can only be filled at 80% due to spill control.
Just like Genesis, it has 4 x 550 gallon fuel tank but can only be filled to 2000 gallons .

[Jtgshu]

Yes, 66, both pans are live at all times (as far as I know - must assume they are anyway) Its just that one is in contact with the wire, the other isn't. There is no chance of arc'ing with a '46 because the way to change pantographs is to raise the one that was down, so they are both up, once that one makes contact, the one that was up before and will be lowered, so there is actually no time when there isnt' a pantograph on the wire. a 45 only has one, so when that is lowered, contact with the wire is lost, and a chance for an arc happens. there are also special instructions about where a "Routine 6" - aka locomotive reset on an ALP can be done, as when that is done, ALL pantographs are lowered and removed from the wire (and the battery opened up, to make the loco completely dead for a little bit and then its livened back up) so there is also a risk for an Arc in some places when a routine 6 is done.

The MandE has (or had) signs all though the roseville cut that say "Low Clearance - Pantographs not to be lowered at this location" or something like that for this very reason. They were under the overhead bridges.

[ns3010]

What is the traction HP when the ALP is supplying HEP? It is listed as having 4200 HP in diesel mode, but it is not clear if that is total or traction only.

The PL42's is listed as having 3620 HP, which is for traction only after the HEP draw. However, the P40's are listed as having 4250 HP, which is total before HEP draw. The differences between the P40 and PL42 listing are the cause for the confusion over which number the ALP's 4200 HP is quoted for.

Sorry if that's confusing, so basically what I'm asking is, do the ALP-45's have 4200 HP of traction, or is it somewhere around the upper/mid 3000's like the P40's and PL42's traction rating?

[kilroy]

Exhaust has already gone thru the combustion process, it can't burn a second time.....

Are you sure about that?

http://pro2am.rrpicturearchives.net/sho ... x?id=67023

[25Hz]

What is the traction HP when the ALP is supplying HEP? It is listed as having 4200 HP in diesel mode, but it is not clear if that is total or traction only.

The PL42's is listed as having 3620 HP, which is for traction only after the HEP draw. However, the P40's are listed as having 4250 HP, which is total before HEP draw. The differences between the P40 and PL42 listing are the cause for the confusion over which number the ALP's 4200 HP is quoted for.

Sorry if that's confusing, so basically what I'm asking is, do the ALP-45's have 4200 HP of traction, or is it somewhere around the upper/mid 3000's like the P40's and PL42's traction rating?

The P40's were re-configured to provide P42 HP rating. It is my understanding that there are some differences in their trucks, and in the engine compartment and some other small things that will remain regardless of HP rating increases.


The ALP-45 in E mode puts out about 5300 HP to the rail head (not sure if that is HEP on or off), in D mode it drops to around 3400 HP as far as what i've read.

[Jtgshu]

This is where things get a little confusing.....

I can only speak for the PLs as thats what im familiar with right now, but on the various computer screens its shows real time ratings of horsepower from the engine/traction alternator. It also shows real time "traction horsepower" -

Im going to give rough numbers, and some of you brainiacs can figure it out, im just going to put out there what the thing says

Max power from diesel engine - 2828MW
With 6 MLs, average HEP consumption is about 300kw, sometimes higher sometimes lower, depending on temperature, if AC or heat is on, number of open cars, etc
Often shows "traction horsepower" of around 4050HP on average (it fluctuates).

IIRC, there are 5 inverter banks, 4 for traction (one for each axle) and 1 for HEP. I do not know if that 4050HP number is the actual amount of power going into the 5 inverter banks, THEN the HEP power comes out of it, or if the reduction in power to 4050 is the power after the HEP is taken out and thats what remains for traction power. Put another way, I don't know if the reduction to 4050HP are the various loads on the engine (blowers, water pumps, AC compressor, etc) sucking power from the engine while its running, or if that number is the actual amount of horsepower being delivered to the wheels, without HEP draw or with HEP draw.

There is also a traction gauge, which again, on average shows around 85 percent of power of the loco going to traction (less if more cars and more HEP load, less if less cars or HEP mode), but doesn't show it as a number in horsepower, but just a percentage. Some locos are better than others, I had one last night that was at 90 percent to traction power, and it was quicker than some others. Why? I have no idea.

[baldwr]

JT / 66 - thanks for the follow-up on the ALP-46 direction change. In my original question, I was only thinking about the lowering pantograph breaking a current carrying circuit which it is. Since the other pantograph is up, however, the voltage differential between the lowering pan and the overhead are the same. Two things are needed to generate the arc - 1) Interrupting current and 2) a voltage difference between the two contact points.

FanRailer - I appreciate your response with regard to the circuit diagram. This answers another question I had... It looks like there is not a circuit breaker between the pan and the primary side of the transformer. If this were the case, you could open the primary breaker and de-energize the transformer. This would allow you to lower the pan (assuming this can be done with battery power) without risk of an arc since there would be no load. But its not the case... Oh well.

I agree with both Dutch and Don31 regarding the flammability of Diesel Exhaust... That should be a non issue. I work on plenty of 2MW and 3MW diesel generators with on-board circuit breakers right in the alternator on the skid. When they trip due to overcurrent (time delay or instantaneous), a healthy arch can be drawn. This equipment is designed to contain the arch, but you are still in close proximity to your on-board fuel store, the fuel fill point, and the prime mover. In NYC, there are plenty of places where the exhaust from a stand-by generator is 10-15 feet above sidewalk level. You do not see No Smoking signs in these areas because it is a non-issue... Don't be fooled by the photo a few posts back. That is of a locomotive with a failed turbo. The point of the turbo is to recover the un-combusted gasses and burn them off. If the turbo is failed, there are still combustible gasses in the exhaust, and the resulting fire happens.