Traction Motors?

Patrick Jun 12, 2000

  1. Patrick

    Patrick Guest

    0
    0
    0
    Are the drive motors called traction motors because the traction for the engine is developed through the motors? Also, how do you tell if an engine has dymamic brakes and how do they work? I know, elementary questions, but I'm learning, I think [​IMG].

    ------------------
    Residing in BNSF's St. Croix Subdivision near Trempealeau, WI
     
  2. DRGWEngr

    DRGWEngr TrainBoard Member

    135
    0
    20
    Patrick, Traction motors are motors on the axles of the loco. Electrical current from the main Altenator is fed into the traction motor thru cables. This turns the motor which has a small gear attached on one side. this gear meshes with a large gear on the inside of the wheel.

    Dynamic brakes turn the traction motors into generators. The resistence tries to keep the wheels from turning thus slowing the train down or helping maintain speed on downhill grades. The resistence can be adjusted by using the dynamic brake handle on the control stand. More resistence more braking power. All of the electicity generated by the traction motors goes back thru the cables to the Dynamic brake grids and disipated as heat. On EMD's until the SD50 the grids are on the center of the long hood above the diesel engine. On SD50-70 the grids are right behind the cab. SD90 has them at the very end of the long hood behind the radiators. On older GE u-boats the grids were in the rear under the radiators using the smaller front intake grills. The newer GE's they are the 2-3 grills behind the cab, intake on the engineers side venting out the firemans side.
    All the other designs intake from the sides and vent out the top. Also on EMD's GP's have one dynamic brake fan either 36" or 48" F's thru GP9's, 48" on the rest. SD's have to fans 36" on SD7,9 and 24's, 48" on the rest.

    I hope this helps, maybe some one can give you an idea such as magazines or books to help you even more.

    Don't be afraid to aks questions, we were all there once.

    Mike
    Windsor,CO
     
  3. Alan

    Alan Staff Member TrainBoard Supporter

    10,798
    460
    127
  4. Patrick

    Patrick Guest

    0
    0
    0
    Thanks very much for the great explanation Mike [​IMG]. I'm going to copy your post and add it to my collection of information that I keep in a Trains & Things notebook I started for proto type and model railroading. Your response is an another example of why this Train Board is my favorite site.

    ------------------
    Residing in BNSF's St. Croix Subdivision near Trempealeau, WI
     
  5. DRGWEngr

    DRGWEngr TrainBoard Member

    135
    0
    20
    Patrick and Alan,
    I tried to explain it as simpley as I could with out writing a novel.

    There's got to be some magazine articles or books or something that you could get your hands on to explain things more clearly yet more detailed.

    Try finding a book called "The railroad,what it is,What it does." Simmons-Bordman? Goes indepth about railroading from the basic roadbed to marketing and managment.

    Take care

    Mike
    Windsor,CO
     
  6. Alan

    Alan Staff Member TrainBoard Supporter

    10,798
    460
    127
  7. Patrick

    Patrick Guest

    0
    0
    0
    <BLOCKQUOTE>quote:</font><HR>Originally posted by DRGWEngr:

    Try finding a book called "The railroad,what it is,What it does."
    <HR></BLOCKQUOTE>

    Hi Mike,

    Thanks for the pointer to the book [​IMG]. I'll check out the library and/or Amazon to see if I can get my hands on a copy. It sounds like it will be a big help to me.

    Another question came up yesterday as I was reading my copy of CTC Board for June during lunch. An article about some former SP DASH 9-44CWs being assigned to the I-5 Corridor because they are not CCS capable leaders. Something to do with cab signals [​IMG]?

    Anyway, thanks again Mike for the great explanation and pointing out the book.

    Patrick

    ------------------
    Residing in BNSF's St. Croix Subdivision near Trempealeau, WI



    [This message has been edited by Patrick (edited 15 June 2000).]
     
  8. DRGWEngr

    DRGWEngr TrainBoard Member

    135
    0
    20
    <BLOCKQUOTE>quote:</font><HR>Originally posted by Patrick:
    Another question came up yesterday as I was reading my copy of CTC Board for June during lunch. An article about some former SP DASH 9-44CWs being assigned to the I-5 Corridor because they are not CCS capable leaders. Something to do with cab signals [​IMG]?

    Patrick

    <HR></BLOCKQUOTE>

    None of the SP locomotives had cab signals so they can't be leaders in cab signal territory. I don't know if UP is going to equip them with ccs or not,haven't see any yet. I'm not familiar with how cab signals work or why they're only used on certain lines.

    Mike
     
  9. DaveCN5710

    DaveCN5710 Profile Locked

    446
    0
    19
    <BLOCKQUOTE>quote:</font><HR>Originally posted by DRGWEngr:
    Patrick, Traction motors are motors on the axles of the loco. Electrical current from the main Altenator is fed into the traction motor thru cables. This turns the motor which has a small gear attached on one side. this gear meshes with a large gear on the inside of the wheel.

    Dynamic brakes turn the traction motors into generators. The resistence tries to keep the wheels from turning thus slowing the train down or helping maintain speed on downhill grades. The resistence can be adjusted by using the dynamic brake handle on the control stand. More resistence more braking power. All of the electicity generated by the traction motors goes back thru the cables to the Dynamic brake grids and disipated as heat. On EMD's until the SD50 the grids are on the center of the long hood above the diesel engine. On SD50-70 the grids are right behind the cab. SD90 has them at the very end of the long hood behind the radiators. On older GE u-boats the grids were in the rear under the radiators using the smaller front intake grills. The newer GE's they are the 2-3 grills behind the cab, intake on the engineers side venting out the firemans side.
    All the other designs intake from the sides and vent out the top. Also on EMD's GP's have one dynamic brake fan either 36" or 48" F's thru GP9's, 48" on the rest. SD's have to fans 36" on SD7,9 and 24's, 48" on the rest.

    I hope this helps, maybe some one can give you an idea such as magazines or books to help you even more.

    Don't be afraid to aks questions, we were all there once.

    Mike
    Windsor,CO

    <HR></BLOCKQUOTE>DRGW saved me alot of typing , he is correct

    :D
     
  10. Gregg Mahlkov

    Gregg Mahlkov Guest

    0
    0
    0
    The reason they are called "traction" motors goes back to the 19th century and the trolley car. Actually, what we refer to as Diesel locomotives are Diesel-electric locomotives and are basically an electic locomotive that carries its own generating station. Trolley cars were powered by electric "traction" and opposed to the regular railroad, which were powered by steam "traction". Electric railways became known as "Traction Companies" and the electric motors that moved them down the track became known as "traction motors". Until the advent of AC power, even the voltage of the Diesel-electric locomotive was the same as the old trolley cars - 600 volts DC. Thought you'd like to know how the name originated as well as what it does. ;)
     

Share This Page