GEVO Locomotives-What's the difference?

Next, why would you want an eight wheel truck, but only six of them actually have traction motors?  What's the point of the two floating wheels?  This would be my C4 model question.

Usually that is for spreading the weight over more wheels, so that the loco can run on lighter gauge track, such as branch lines.

Yardmaster96,

There are books written about this subject.  You should probably Google your questions or buy one of the books.  Here are some basics:

1.  To my knowledge, none of the major diesel manufacturers are making diesels with 8 wheel trucks.  All mainline diesels currently being made have 6 wheel trucks.   This means each truck has 3 axels.  

2.  DC traction motors are less expensive to make and buy than AC traction motors.  AC traction motors, however, can handle more current which makes them more suitable for heavy haul duty such as unit coal trains.  Also, AC motors cost less to maintain than DC motors.  

3.  A six wheel diesel truck with all axels powered is called a C truck.  Most modern diesels have a C-C truck arrangement.  This means that both trucks have all three axels powered.

 A truck with an unpowered axel is called an A-1-A truck.  This means that the first axel is powered, the second does not have a motor, and the third is powered.  There are two powered axels per truck.  This is also called the C4 arrangement by GE.  It means that only 4 of the six axels on the diesel are powered.  

 Sometimes a railroad does not need to have all the axels of its diesels powered for a particular service.  The railroad saves on maintenance and initial cost by buying only the number of motors that are needed.

4.  Most mainline diesels today have 4,000 to 4,400 horsepower engines.  Railroads have found that this is the best HP range per diesel engine to build multiple power units to get a particular train over the road.   More or less horsepower per diesel is less economic.  

I hope this helps.  NH Joe

New Haven Joe posted:

Yardmaster96,

There are books written about this subject.  You should probably Google your questions or buy one of the books.  Here are some basics:

1.  To my knowledge, none of the major diesel manufacturers are making diesels with 8 wheel trucks.  All mainline diesels currently being made have 6 wheel trucks.   This means each truck has 3 axels.  

2.  DC traction motors are less expensive to make and buy than AC traction motors.  AC traction motors, however, can handle more current which makes them more suitable for heavy haul duty such as unit coal trains.  Also, AC motors cost less to maintain than DC motors.  

 

To be correct, "current" has nothing do with the superior power capabilities of the three phase induction motor, used in AC traction diesel locomotives. You might want to Google THAT.

 

 

Get a copy of "GE EVOLUTION LOCOMOTIVES" by Sean Graham-White it will answer most of your  GEVO questions. 

Thanks Paul.  And thanks to all the other replies.  I had no idea there was a book on them.  That's why I come here first. 

New Haven Joe posted:

Yardmaster96,

There are books written about this subject.  You should probably Google your questions or buy one of the books.  Here are some basics:

1.  To my knowledge, none of the major diesel manufacturers are making diesels with 8 wheel trucks.  All mainline diesels currently being made have 6 wheel trucks.   This means each truck has 3 axels.  

 

 

Added for trivia:

EMD made some SD45 variants in the 1970's with these trucks for the meter narrow-gauge railroads in Brazil. While not quite the same idea, GE also made some export units with BB-BB wheel arrangements for the same market, and (supposedly) they've floated a proposal to dust off this solution for White Pass & Yukon, who's new management is looking for motive power to haul longer tourist trains on their 3' gauge trackage (the available traction motors that would fit a 3' gauge wheelset cannot handle the power output of modern diesels in a C-C configuration, but a D-D or BB-BB would work).

---PCJ

PCJ

Thanks for the education.  I found the book by Sean Graham White on ebay for $40.  I plan to buy that one.  But any and all information as to the reasoning behind different models is a great interest of mine.  I'm the kind of person who when someone comes to me and says, I saw a turbo version of a two wheeled skateboard.  I don't ask, "why turbo", I ask, "who the heck wants a two wheeled skateboard when you can buy the four wheeled version and have more stability?"  Then someone tells me there is a movement in the skateboard industry to make it more challenging using two wheels instead of four, it's catching on in vegas.  That's when I say, "did not know that.  Thanks for the education."  So hopefully I didn't come across as downing the DC versions or thinking a floating wheel on truck set was dumb.  I just had no idea why someone would want to do that.  Now I know.