Interesting Zimo decoder feature ........

DCESharkman Jan 12, 2019

  1. DCESharkman

    DCESharkman TrainBoard Member

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    Well hello everyone. First of all, I am not trying to start a decoder war. I just wanted to share something that may have been missed. Zimo has a second level of trim control.

    upload_2019-1-12_7-27-1.png

    You can add or subtract trim from the initial settings
    upload_2019-1-12_7-28-58.png

    The application I see with this may or may not be of interest. But for those modelers that want to run distributed power like the prototype, here is a way to do that.

    First, you need to make sure all your locomotives are closely speed matched. This is both at full throttle and at a slow throttles setting like 10. This is so you can match the initial kick start of the locomotives, you do not want the mid-train helpers to jump out faster than the lead locomotives.

    With that in play, it becomes a little bit of trial and error to sync the locomotive motion for all of the locomotives.

    First all of your lead locomotives have no adjustment in the trim.

    You add additional trim to the mid-train helpers, this must be proportional to the slack time of the number of cars between the locomotives sets. Note this will change as the car counts change between the locomotive sets. I will give an example if this shortly. If you want to add pushers on the end of the train you just repeat the process and if the car counts are the same between the mid-train helpers and the pushers you would just double the trim addition on those locomotives.

    When you want to decelerate, you just go backwards on the train adding trim. Leave as set on the pushers, increase the deceleration trim on the helpers and then following the pattern double that on the lead locomotives.

    Here is what I did. Since I do not have a long enough layout for say 100 cars handy right now, I assigned a value of 3 seconds of delay to represent 50 cars

    On the Head End Locomotives I leave acceleration setting as is
    On the Helpers I set additional acceleration trim to 3
    On the Pushers I set additional acceleration trim to 6

    Realizing that the back of the train needs to slow down faster than the front, I reverse the settings:

    On the Head End Locomotives I set decceleration trim to 6
    On the Helpers I set additional decceleration trim to 3
    On the Pushers I leave acceleration setting as is

    My test track is a long oval the length of 2 HCD's laid end to end.

    I verify that all of the locomotives are properly speed matched over 5 laps around the track making just small adjustments here and there.

    Next I lash up the head end units, the Helpers and the Pushers and set them all in the same consist.

    Next I take a 12 inch ruler between the Head End and the Helpers and a 12 inch ruler between the Helpers and the Pushers

    Next I go and let them go forward at an initial throttle setting of 20, then 50 then 80 percent throttle and it looks good, Helpers started moving right almost right on 3 seconds and the Pushers at very close to 6 seconds using my cell phone stopwatch.

    So far things are reasonable good and I let them circle the track 10 times before I lower the throttle to 50 percent and a lap later to 20 percent and a lap later to 0 percent.

    Time for the measurements:

    I lay the 12 inch ruler between the Head End and the Helpers and the distance is 11.75 inches
    I lay the 12 inch ruler between the Helpers and the Pushers and I get 11.825 inches

    So I am pretty close for a first try.

    Took me a little bit to see that the Helpers slowed a tad too fast. And the Pushers sped up just a tad too fast.

    Here are the final results:

    On the Head End Locomotives I leave acceleration setting as is
    On the Helpers I set additional acceleration trim to 3
    On the Pushers I set additional acceleration trim to 7

    Realizing that the back of the train needs to slow down faster than the front, I reverse the settings:

    On the Head End Locomotives I set decceleration trim to 6
    On the Helpers I set additional decceleration trim to 4
    On the Pushers I leave acceleration setting as is

    Ran the same test at 20, 50 and 80 percent of the throttle and the ten laps.

    When I deccelerated to 0 and measured again the 12 inch ruler rested on the couplers between the Head End unit and the Helpers, and the Helpers and the Pushers.

    I still need to figure a time versus car relationship, but from a DCC perspective the distributed power is potentially solved.

    All locomotives used in the testing were Fox Valley Models Gevo's with Zimo MX621N Version 31 decoders.
    They all had the same speed tables and were all sped matched before the testing. The maximum scale speed for the test was 75 smph verified with the Accutrak Speedometer.

    Up next is figuring out the Car/Time question.
     
    Dogwood likes this.
  2. Dogwood

    Dogwood TrainBoard Member

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    Everything ok and plausible. But, the only manufacturer where that works is in my opinion Kato. All others have too many differences at the factory. Especially at Atlas N. Kato with ESU decoder runs very well.

    Simple but expensive is this software:
    http://www.freiwaldsoftware.de/pages/traincontroller_gold.htm
    I've been thinking too long to invest in it. I have 82 locos, that's worth it .....
     
  3. DCESharkman

    DCESharkman TrainBoard Member

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    I did this using FVM locomotives that I have found to be quite reliable. I do not have any Zimo decoders in any of my Kato locomotives. I have all my Kato and FVM locomotives speed matched so they run fine together. But it is the trim on the momentum settings that make the process work. It is possible that I could inter-mix the Kato and FVM with the Kato all on the Head End and modify the decelleration momentum to get it close.

    I do agree to a point on the Atlas locomotives like the SD60 and SD60M locomotives, they are a mixed jar of nuts. I can only get them to work under head end power only. Again no Zimo decoders are made for the Atlas locomotives and ESU for what I can see doe not off this capability. They are great decoders too.
     
  4. jdcolombo

    jdcolombo TrainBoard Member

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    Zimo's decoders are probably the best out there from the standpoint of motor control capability. I sat down with the manual once and realized there was WAY more stuff you could do to fine tune Zimo's operation than I could absorb. You've hit on one example, but you can also almost infinitely tune the BEMF parameters, too.

    If it wasn't for wanting to go with ESU's sound decoders and then wanting all my non-sound decoders to match, I'd use Zimo.

    John C.
     
  5. DCESharkman

    DCESharkman TrainBoard Member

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    Hi John,

    Well I agree with you on standardizing on ESU for many reasons. I used Zimo before I knew about ESU and had started using the MX621 when the FVM locomotives started rolling out. It was a few few years later when ESU really landed with the sound decoders. But I have heard that there is a major push at Zimo to add more US sound profiles for their sound decoders, which still have these same features in my post today.

    And to be quite honest, this dawned on me not long ago due to the barrage of speed matching locomotives I went through. After I got through the Digitrax decoders I still have installed, I started on the FVM GEVO's. I just decided to look on some of the panels in JMRI when I stumbled on this solution.

    I have Zimo decoders in all my FVM locomotives at this time. So I can do the same with the GP60's and the SD70ACe locomotives from FVM. I just do not have enough of the latter to do a distributed power configuration.

    I just saw the JMRI tab and read it closely. I never knew that feature was there until recently.
     
  6. DCESharkman

    DCESharkman TrainBoard Member

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    Well it is time for an update - Not much was unexpected. It is simple enough to place Kato locomotives with Digitrax or TCS decoders as the lead engines with asymmetrical momentum and then connect Zimo locomotives in the mid-train slot and the rear pusher slot. It takes some time to adjust the Zimo decoders. But the results are pretty good. This tells me that different decoder consists can be able to work by adjusting the Zimo decoders to work with the non-Zimo decoders.

    That said, it did take a long time to match the Zimo to the Kato locomotives with either Digitrax or TCS decoders. That added about 3 hours to the process.
    With that said, I think I will be replacing Digitrax and TCS decoders with Zimo decoders for all distributed power lashups.

    I have nothing against Digitrax, Lenz, NCE or TCS decoders, I still have many locomotives that have these assorted decoders. It is more the time element that makes this decision.
     
  7. Keith Ledbetter

    Keith Ledbetter TrainBoard Member

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    Yes you hit the nail on the head. The reality is for most sticking with one brand helps save massive amounts of time due to consistancy as well as the learning curve of all that they do and they all do it differently. ZIMO is a great brand and I agree probably actually the best as far as motor control and tweaking wise but that is no knock on the others. I generally stick with ESU unle1ss there is an easy drop in for another that I dont care about sound on.
     
  8. jdcolombo

    jdcolombo TrainBoard Member

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    I decided about three years ago that trying to program different decoders to get them to run well with each other was doable, but just too much trouble. So I tore out all the TCS and Lenz decoders I had, and replaced them all with ESU (LokPilot for motor-only; LokSound for sound). I'm having the same issues now helping a friend with his large HO layout and engines that have decoders from QSI, Soundtraxx, NCE, ESU and BLI (Paragon). Getting them to run together is doable but difficult. Some of them don't use a 3-point speed table (Soundtraxx Tsunami I); every manufacturer implements momentum on a different "scale" - so a setting of 20 in one decoder isn't even close to 20 in another. So I've convinced him to switch everything (gradually - since we're talking about 100 locos) to ESU. Throwing out perfectly good older decoders may not be economically efficient, but from a time perspective it just makes everything light-years easier.

    John C.
     
  9. Point353

    Point353 TrainBoard Member

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    Does your test layout have any grades?
    Are your loco decoder settings always valid regardless of whether the slack is fully in, completely stretched out - or anywhere in between?
     
  10. DCESharkman

    DCESharkman TrainBoard Member

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    Indeed John! Time is a very valuable commodity. That is why I am not going to spend the extra time forcing a square head into a round hole, ie making Zimo play with other decoders.

    Unfortunately, the volume of decoders I have already installed makes that extremely cost prohibitive, the number far and away exceed 100 locomotives. So I will just be grouping like locomotives with like decoders. Upon replacement, I will look at moving the locomotive to either ESU or Zimo depending on how they will be used. I have spent the better part of a week trying to get my ESU locomotives to track like Zimo units for distributed power, and so far it has been a dismal failure. I am not that big a fan of sound on the locomotives so that is not my deciding factor. For sound on the distributed power, I may just go with sound cars around the locomotives and stay with the Zimo motion decoders. I will continue to use ESU for all sound decoders. They can be speed matched really well with non sound ESU decoders for head end consists.

    And lastly, there is one last consideration, the amount of work to the amount of enjoyment running, that is priceless!
     
  11. DCESharkman

    DCESharkman TrainBoard Member

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    Hello, my test track has a mild 1% grade (slope of the garage floor).

    I did run a set of locomotives on my full layout which has up to 2.5% grades and there were no issues either going up or down hill. The cars were never really stretched out or fully in, they were happy somewhere in between. This was with 130 cars between the head end and the mit-train helpers and then another 120 cars between the helpers and the rear pushers. I only had a few hours to run but I saw no issues going at speed for 2 hours going through crossovers, around curves and up and down grades. There were no derailments and no disconnects.
     

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