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GE ET44 (Tier 4 GEVOs) - Air Compressor?

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Posted by SD70Dude on Tuesday, January 1, 2019 7:04 PM

I also wouldn't be surprised if the different railroads have programmed their locomotives to operate differently, just like having different operating instructions.

The older stuff is way better to switch with anyway!

Greetings from Alberta

-an Articulate Malcontent

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Posted by zugmann on Tuesday, January 1, 2019 7:01 PM

I'll take your word for it.  Been a while since I ran newer crap.

Our rebuilt SD60s automatically notch up to about 3 or so when charging, so there really isn't much to do. 

It's been fun.  But it isn't much fun anymore.   Signing off for now. 


  

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Posted by SD70Dude on Tuesday, January 1, 2019 6:53 PM

zugmann
SD70Dude
The GE control stand bears a notice stating "this locomotive is fitted with a motor-driven air compressor. Optimum train charging is achieved in notch 1".

Don't you mean EMD?  And isn't it usually notch 2?

Nope, GE.  I've seen it on Dash-8's, Dash-9's and GEVO's.  

EMD compressors (except perhaps on the SD70ACe-T4) are directly driven by the crankshaft, so the faster the engine revs, the more air you pump.  Our operating manual says to keep it to notch 4 or lower when in neutral, but on a lot of the SD60's and older units you need more, especially with only one unit pumping up long cuts.  

Starting with the SD70's the computer automatically revs it up to what sounds like notch 6 to pump air.  SD60's do that too but only up to notch 3 or 4, and anything older just idles away while your MR pressure drops, waiting for you to rev it up.

Greetings from Alberta

-an Articulate Malcontent

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Posted by zugmann on Tuesday, January 1, 2019 5:46 PM

SD70Dude
The GE control stand bears a notice stating "this locomotive is fitted with a motor-driven air compressor. Optimum train charging is achieved in notch 1".

Don't you mean EMD?  And isn't it usually notch 2?

It's been fun.  But it isn't much fun anymore.   Signing off for now. 


  

The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any

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Posted by SD70Dude on Tuesday, January 1, 2019 5:16 PM

The GE compressor is indeed electrically driven.  When much air is demanded (such as when charging a train) the engine May rev up a couple notches, I suspect to ensure that the auxiliary generator is able to supply the power demanded of it.

The GE control stand bears a notice stating "this locomotive is fitted with a motor-driven air compressor.  Optimum train charging is achieved in notch 1".

Greetings from Alberta

-an Articulate Malcontent

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Posted by IAFarmer on Monday, December 31, 2018 9:31 AM

That sound is indeed the air compressor.  not sure what the tier 4s have but Im pretty sure its electric drive. 

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Posted by Metro Red Line on Saturday, December 1, 2018 10:23 PM

M636C

The only Australian locomotives which gave the "whoop" sound were the 120 Cv40-9i units. None of the subsequent C44ACi units (more than 200 units) had this sound. All of the Cv40-9i units have been rebuilt with new electronics. Although they kept the original compressor, the distinctive sound disappeared. I was told that the sound was due to the particular starting arrangements, not a feature of the compressor itself.

So it seems unlikely that new GE locomotives would have the sound, since they would use the new starting arrangements.

Peter

 



Thanks for the insight. Would like to hear confirmation about this on the North American GE ET44 locos though. I have a model ET44 with DCC sound and on the MR forums, a few of us were wondering about the "Whoop" since the sound decoder doesn't make that sound. If indeed the prototype lacks it, then we can rest easy knowing that it wasn't a feature of the prototype in the first place. 

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Posted by M636C on Friday, November 30, 2018 5:10 AM

Metro Red Line

Does anyone know what kind of air compressor does the ET44s have? Is it the standard "Whoop" compressor that GE uses on their locos, or a different type?

 

The only Australian locomotives which gave the "whoop" sound were the 120 Cv40-9i units. None of the subsequent C44ACi units (more than 200 units) had this sound. All of the Cv40-9i units have been rebuilt with new electronics. Although they kept the original compressor, the distinctive sound disappeared. I was told that the sound was due to the particular starting arrangements, not a feature of the compressor itself.

So it seems unlikely that new GE locomotives would have the sound, since they would use the new starting arrangements.

Peter

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Posted by NorthWest on Thursday, November 29, 2018 8:34 PM

I've been told that the whoop is actually the radiator fan kicking in, rather than the air compressor.

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GE ET44 (Tier 4 GEVOs) - Air Compressor?
Posted by Metro Red Line on Thursday, November 29, 2018 4:57 PM

Does anyone know what kind of air compressor does the ET44s have? Is it the standard "Whoop" compressor that GE uses on their locos, or a different type?

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