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  • How do GenSets work in MU?

  • General discussion about locomotives, rolling stock, and equipment
General discussion about locomotives, rolling stock, and equipment

Moderator: John_Perkowski

 #697558  by railfan365
 
I already know that the distinguishing feature of GenSets is that instead of having one big engine that is good for the maximum total horsepower of the locomotive, it has three engines that are each good for up to 1/3. During a run, engines will start and stop as necessary to have one engine working when the power demand is low, two engines working for moderate power demand, and all three for high power demand.

With that background restated for clarity, my question is: When several GenSet locomotives are lashed togethier for MU operation, does each locomotive have at least one engine going at all times, or do all of the engines become one big series with one or more whole locomotives shutting down when peak power is not needed?

Moderator's note: Topic moved to the "General Discussion: Locomotives, Rolling Stock & Equipment" forum. Aa3rt
 #697816  by ex Budd man
 
I would imagine that each would respond to the throttle the same way, so if two or more are coupled each would run on one engine until the throttle was opened to the fifth notch. Once in run five the next gen-set would start, doubling the power and so on. MUing more than two seems silly, dragging extra power around that might not be used.
 #697962  by FCP503
 
railfan365 wrote: When several GenSet locomotives are lashed togethier for MU operation, does each locomotive have at least one engine going at all times, or do all of the engines become one big series with one or more whole locomotives shutting down when peak power is not needed?
Yes, one a genset one engine needs to stay running all the time in order to keep the batteries topped off, to provide power for the air compressor, etc.

it is important to understand that a typical diesel electric locomotive has two seperate electrical systems. The main generator/alternator, traction motors, and if equippped dynamic brake resistors, are all part of the high voltage, (600volt) system. This is a seperate, self contained system for each unit.

The only differnance with a genset is that there are multiple independantly powered alternators on board each unit.

Headlights, MU control, and all the other auxilary electrical devices are part of the low voltage 74volt DC system.

The only point where locomotives are connected electrically is in the curcuits that control engine throttle position, reverser position, dynamic brake control, etc. There is also some limited connection in the headlight circuits as well.