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  • SC-44 Siemens Charger Locomotives

  • 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

 #1455639  by DutchRailnut
 
they don't,
they have blended brakes it uses dynamics as part of total brake system, there is no separate dynamic brake.
 #1455647  by ApproachMedium
 
All wrong. They have dynamic brake. The throttle is the same as the ACS 64 where one way is power and one way is electric brake. It does not have a setup time like the older diesels did where you had to wait for it to change from one to the other. You can go directly from powering to braking, but you would not want to with a passenger train as that makes for harsh train handling. There is a blended braking feature on the pneumatic air brake system that will use the dynamic and air combined, but that feature has been around for quite a while with modern passenger locomotives.
 #1455650  by F-line to Dudley via Park
 
The latest generation of energy recapture tech for regenerative braking works better with a hybridized mix of blended + dynamic brakes in order to recoup the maximum amount of braking energy as recirculated electricity for traction and/or HEP (with all the associated fuel/emissions savings that entails). So you don't see much 'pure' dynamic braking on the state-of-the-art current generation of loco families. Siemens Charger + Sprinter, EMD F125, Bombardier ALP-46A & 45DP, MPI HSP-46, the latest GE Evolution freight makes like the Tier 4 ET44AC + scores of older ES44AC's being rebuilt to newer-spec, tons and tons of newer Euro power, and on and on...they all go with some optimized-to-task mixture of dynamic, blended, regen, and electropneumatic braking systems. It's simply how 21st century power gets built.
 #1455779  by dowlingm
 
ApproachMedium wrote:You only like them because you dont have to deal with running them, fixing them, or the damage and destruction they do to the tracks after they pound over them.
Switching to 60Hz across NJT and transformer core replacement would make them a smidge lighter tho

( /me gets coat, runs away fast )
 #1455782  by Backshophoss
 
Believe any chance to covert the PRR/Amtrak grid to 60hz power has sailed for now,you need to change too many substations and generating stations
from 25 hz,and trying to get SEPTA to upgrade is a lost cause $$$$$$$ wise.
 #1455803  by BandA
 
Is there a phase break between every substation feed? If so, then you theoretically could switch from 60hz-25hz-60hz-25hz-60hz etc.
 #1455804  by ApproachMedium
 
BandA wrote:Is there a phase break between every substation feed? If so, then you theoretically could switch from 60hz-25hz-60hz-25hz-60hz etc.
No, the entire corridor from Gate interlocking to harrisburg and DC is fully phase synchronized. There is only one section break down by Perryville but it is always hot and does not require any action from the engineer unless the north and south half of the railroad go out of phase sync. Otherwise, they stay completely the same. The level of complications involved in breaking down the NEC would be massive and expensive and frankly if we had that money to spend we have bridges ready to fall in the water and a tunnel that needs to be built. Theres nothing wrong with the current power delivery system, it works.
 #1455815  by east point
 
Backshophoss wrote:Believe any chance to covert the PRR/Amtrak grid to 60hz power has sailed for now,you need to change too many substations and generating stations
from 25 hz,and trying to get SEPTA to upgrade is a lost cause $$$$$$$ wise.
Actually all transformers that are now being replaced are dual frequency transformers. As the 25 hZ equipment becomes obsolete or more likely not financially repairable that equipment is replaced with dual frequency equipment. However do not get up your hopes very high. Most of the PRR equipment was overbuilt and is very reliable. Also some early Amtrak replacements were 25 hZ only. Expect that it will take 40 -50 years for everything to become 60 hZ compatible. Much switch gear is still only 25 hZ. A small advantage when finally going to 60 hZ is the 500 nominal increase in CAT voltage. Nominal would be 12.5 kV +/- 10%.

As for generating stations --------- all the rotary converters and solid state frequency converters could just be switched off and bypassed. As a section is converted we probably can expect any converters that have life moved to replace equipment that is obsolete. Safe harbor generating station is slightly different but since Amtrak has first call for its power Safe Harbor would just cut back on their 60 hZ to commercial customers until their single phase generators could be replaced. Safe Harbor does have both 25 and 60 hZ generators.
 #1456178  by gokeefe
 
An interesting question came up in the Auto Train thread which to my knowledge has not been answered here regarding the Chargers.

Will/Are they able to run with multiple units providing synced HEP?
 #1456217  by F-line to Dudley via Park
 
gokeefe wrote:An interesting question came up in the Auto Train thread which to my knowledge has not been answered here regarding the Chargers.

Will/Are they able to run with multiple units providing synced HEP?
I'm pretty sure existing units don't, and the national options won't because the only major hardware differentiator is larger fuel tank.
 #1456223  by DutchRailnut
 
no need to synchronise hep, the HEP is rated at one megawatt which is the maximum for HEP cable system .
 #1457393  by Fan Railer
 
DutchRailnut wrote:no need to synchronise hep, the HEP is rated at one megawatt which is the maximum for HEP cable system .
While the 1000 kW HEP capacity is an option, the corridor spec'd locomotives only come rated for 660 kW HEP.

In other news, MARC ran their Charger test train today on the NEC between WAS and PHL. It will run again tomorrow:
https://youtu.be/xFS_MeWWNds" onclick="window.open(this.href);return false;
 #1457419  by ApproachMedium
 
I saw the two units in DC this evening. They are very quiet at idle, even with the HEP on the lead unit it was still very easy to talk over. These things are still ugly.
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