Lokprogrammer ... CV54 & BEMF

peteyPab Aug 30, 2021

  1. peteyPab

    peteyPab TrainBoard Member

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    Anyone have any advice on resetting the defaults or smoothing out the motor settings? After trying to utilize autotune CV54 numerous times and adjusting a few other values on my lokprogrammer I now have two GP diesels out of commission. I'm not sure what else I can do in order to fix them. They are stuttering and making odd sounds. One is a loksound select micro and the other is a loksound 5.

    I should have never tweaked with any other adjustments.... I was originally trying to increase the voltage reference after the autotune cv54 because they were running much too slow and the engine was notching too many times before getting to a decent speed.
     
  2. tehachapifan

    tehachapifan TrainBoard Member

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    Aside from the speed issue after the CV54 auto adjustment, were they running smooth (before you tried adjusting the voltage reference separately)?
     
  3. RBrodzinsky

    RBrodzinsky November 18, 2022 Staff Member TrainBoard Supporter In Memoriam

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    Even if you do not have the LokProgrammer hardware, you can always download the LP software (if you are running Windows or a Windows emulator) and then open the sound project from the ESU website. This will show you the "default" values (which are simply generic and not tuned for anything), and you can reset them.

    I'm assuming from your post that you are not using a LokProgrammer. If so, then the other way to reset to the initial settings is to simply write 8 to CV8 and then remove power to reset the decoder.
     
  4. freddy_fo

    freddy_fo TrainBoard Member

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    CV 54 ("K") default setting is usually 50 and CV55 ("I") normally defaults to 100. CV53 (reference voltage) should be at 130. Depending on the type of motor and whether or not it uses a flywheel will determine the best settings for that particular loco. First I'd try the reset per RBrodzinsky then check the cv values for those two CVs. If you are running again after the reset and the loco doesn't run like you want then make small adjustments (by 5) on each cv one at a time and test on the 1st speed step. CV 54 if adjusted for jerky movements as the engine is "cruising" at low speed. If there is no flywheel and or the motor is coreless and it runs unevenly then adjust down.

    On some of my setups with flywheels I will adjust in both directions to see where I start seeing improvement. Mostly though I wind up adjusting down.

    CV55 determines how the motor responds to speed input changes. If it is jerky or surges then start adjusting that down in increments of 5. Typically motors with flywheels or heavy rotors are less susceptible to surging using default settings.

    The most recent lokpilot manual on the ESU website explains all this in great detail starting on page 52 section 11.1.2.
     
    Sumner and mtntrainman like this.
  5. peteyPab

    peteyPab TrainBoard Member

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    I do have a lokpgrammer which makes my life easier. The engines are both Atlas and have flywheels. I tried using the default values from the loksound file download and tried doing a few adjustments; however, I can't seem to get the jerky operation out of it. Besides the CV53 AND CV55 would there be any other adjustments I could make? Do I even touch the slow speed settings?
     
  6. RBrodzinsky

    RBrodzinsky November 18, 2022 Staff Member TrainBoard Supporter In Memoriam

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    If you have the LP, then I would reset all the motor tuning settings back to the sound project’s default. Then perform autotune, again. Make sure sound is off and all other functions are off.

    After the CV54=0 / F1 autotune, read the motor function values. The only one I would adjust at this point is reference voltage. I have found a value around 100 (10V) is typically sufficient for most N locos, 130 (13V) for HO. You should have smooth operations on both units, EXCEPT possibly at the slowest crawl. That is where you need to start adjusting K slow upwards. I find values in the low to mid 20s sufficient to give nice smooth slow crawl.
     
  7. freddy_fo

    freddy_fo TrainBoard Member

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    Is it jerky when just starting out or while moving at speed step 1? The I and K adjustments are for slow speed settings and are meant for adjustment/tuning at speed step 1.

    The programmer has a bunch of default motor settings you can select from. It's a link called "use load control values from preset motor types" near the bottom in the motor settings just under the back emf settings section. I usually will try and see if any of those presets work or get me close then adjust manually from there. The back emf settings are for finer tuning but I'd stay away from there until you have got most of the slow speed performance tuned as close as you can get it to your liking.

    I have a few atlas locos with the lokpilot. My GP35 (old kato chassis) uses the following settings:

    Regulation reference: 112
    Reg parameter "k": 80
    Reg parameter "I": 50
     
  8. Carl Sowell

    Carl Sowell TrainBoard Supporter

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    petey,

    I am, by no means, an expert at DCC and I would not doubt what the 2 posters above have suggested. I know Rick is quite learned about, especially ESU, decoders and f_f seems to know what he is talking about, but I have a question for you.

    You mentioned they seemed to be way too slow. Have you looked at or adjusted cv's 2, 5, & 6 along with 3 & 4 ?
    I have never had a problem that you are experiencing with a diesel and I use ESU's.

    Just my 2 cents worth.

    Be well,
    Carl
     
  9. peteyPab

    peteyPab TrainBoard Member

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    Appreciate all the advice. I did find one problem I was doing. After performing the autotune CV54 = 0, I tried performing autotune several more times in hopes to help refine the smoothness. I noticed it deteriorates the performance significantly. I'm assuming it's a one-and-done use... then make refinements elsewhere and avoid using the CV54 again. I was able to go back as Rick had advised to load the default sound decoder values from ESU. My GP39-2 factory direct loksound seems to be working great again. I didn't even adjust any other setting. Thank you.

    My remaining issue is the aftermarket loksound 5 micro in my GP30. It seems to still jerk at low speeds and at higher speeds. Pretty badly. I cleaned out the trucks, gears, contacts and wheels the prior evening to ensure there were no broken teeth, excess lube or foreign debris. I also double checked to make sure no wires from the motor, speaker or board are making accidental contact.

    I currently have it set to the 3 speed default. Below are my current basic and slow settings. Not sure what else I might be missing. Sometimes it seems to work very smoothing at mid speeds, but it has been inconsistent.

    upload_2021-8-30_22-3-58.png

    upload_2021-8-30_21-59-42.png


    upload_2021-8-30_22-5-9.png
     

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