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Load testing Milwaukee Road E9 32A

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Load testing Milwaukee Road E9 32A
Posted by CMStPnP on Sunday, August 15, 2021 8:12 PM

Looks like they load test the engines individually, #1 followed by #2.

https://www.youtube.com/watch?v=4wKgUs6WU8o

 

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Posted by MidlandMike on Sunday, August 15, 2021 9:28 PM

I wonder if each engine/generator powers a separate truck?

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Posted by BaltACD on Sunday, August 15, 2021 10:31 PM

MidlandMike
I wonder if each engine/generator powers a separate truck?

Yes.

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Posted by Lithonia Operator on Monday, August 16, 2021 2:08 AM

The loco is held stationary by only the independent brake and hand brakes?

Still in training.


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Posted by SD70Dude on Monday, August 16, 2021 3:33 AM

Lithonia Operator

The loco is held stationary by only the independent brake and hand brakes? 

No.  Doing so would burn up the traction motors, and at high throttle it would overcome the brakes and start moving anyway.  

During a load test the main generator's output is sent to a large resistor instead of the traction motors.  Most locomotives equipped with dynamic braking are able to use their own DB grid as the resistor, which seems to be the case here (I don't see any cables running out of the locomotive).  

Greetings from Alberta

-an Articulate Malcontent

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Posted by Lithonia Operator on Monday, August 16, 2021 12:42 PM

Aha. That makes more sense!

Thanks, Dude.

Still in training.


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Posted by Overmod on Monday, August 16, 2021 12:59 PM

We've had a number of threads, including at least two in detail with Randy Stahl, that cover loadboxing and load-testing measurement.

Many modern locomotives carry this out simply with special routines in the onboard computers.

I do not remember E units as having one engine devoted to each truck.  The locomotive I remember built that way was the Baldwin Essl locomotive, which was intended to have each 750hp genset drive the axle under it -- to get the drive to 'scale' easily to the number of modular engines actually fired up.  That was not a very good idea and to my knowledge other Baldwins with multiple engines (the Centipedes and BP-20s) used all the TMs all the time.

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Posted by timz on Monday, August 16, 2021 4:22 PM

There's a question -- did any twin-engine locomotive not power each truck by its own engine?

Don't recall whether Baldwin and Lima center-cabs had transition -- if they did, they'd have to go from 3S to 3P, unless they did power each truck with two generators.

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