State of the Art switching in N scale?

[ednadolski]

The ESU decoders have an auto-adjustment routine.  I start with that.  Then I set CV53 (the reference voltage) to 130 if the auto-tune routine changed it.  If I'm happy with the slow speed performance, I stop there.  Usually, however, I do some more fiddling with CV's 51 and 52, which control slow-speed response (and sometimes 54 and 55, which are more overall adjustments).  This is trial and error.  I'll put the engine on the track, crack the throttle open to speed step 1/128, and then use programming on the main to increase/decrease the values in CV51 and 52.  I start with large swings (e.g., adding/subtracting 25) to see the effect I get, and then narrow the range down via iteration.  The ESU LokSound 5 manual has some suggestions for various motors, and over the 100 locos that I've added ESU decoders to, I've figured out some likely values for the various manufacturers I run into (primarily Atlas & Kato).  Once I hit on a combination that works for a specific engine, I save those values via my LokProgrammer and JMRI software for future reference.  I find that those values usually work in similar engines.

John C.

@jdcolombo  any chance you might have some CV values that you use for a Kato loco like an SD40-2 (mid-production) or similar, with a LokSound V5?    I'm trying to see if I can get mine to run around 1 scale mph in speed step 1 of 128.   Currently it does 2.5 smph (measured with the Accu-Track speedometer, which I am not 100% sure of its absolute accuracy) and that is after doing the auto tune.

FWIW here are the CV values that my loco read after doing the auto-tune:

CV51: 032
CV52: 017
CV53: 076
CV54: 044
CV55: 069

Also, I manually program CV3: 0, CV4: 0, CV5: 32, and CV6: 16.

I'm not thinking to actually run much at 1 smph, but I would like to see if I can get it to transition/accelerate from a stop to the first speed step a bit more smoothly.  It's not actually running rough or jerking or such, in fact it runs pretty smooth even at that step 1, it's just that it sort of switches on from a standstill to that first step without any acceleration (even with momentum turned all the way up).  Looking closely at your vid of the RS-3 a few pages back it seems that you've got it starting very smoothly.

TIA,
Ed

[NtheBasement]

I switched to DCC to get better slow speed control for the flood loader.  But when I tried to set speed tables to optimize crawling, locos would crawl for a while then suddenly speed up.  That silliness stopped when I turned off the BEMF.  Could be a bug is in the DZ126 decoder's code.

Fiddling with any pulse width settings is useful.  Also helpful: take off the loco's body and put felt tip marks on a flywheel so you can see it turn.  I was amazed to see my Atlas and Kato motors do <1 RPM; leave em sit for an hour and the loco moves a few inches down the track.  Snail mode.

[Sokramiketes]

Ed-

This video may be helpful. 

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Grant Eastman cares a lot about smooth operation, including effortless slow starts and train dynamics.  He tuned a couple locomotives on the Modutrak layout, in the method laid out in the video, and they are still some of my smoothest. 

Now, it's Digitrax based.  But I think the basics of turning off all back-emf and fiddling with the speed tables would apply.  Its really a video about how best to control Kato motors and mechanisms. 

[Wolf N Works]

I will 2nd Mike’s posting.  Grant has some of the smoothest and nicest running for operations that I have seen

[peteski]

Using momentum (acceleration and deceleration > 0) also greatly aids in improving realism of model locos.