I have two Bowser Execuline F7As that I speed-matched for consist use. Both top out at 41 scale mph going forward, but one goes 49 scale mph in reverse, making it a challenge to pair them back-to-back as they were operated on the prototype. Is there a CV/JMRI setting that could be causing this problem? If not, what are the other possible causes that I should chase down? The decoders are both Soundtraxx (same type in both locos), and my system is NCE. Any suggestions greatly appreciated!
Hello All,
If you plan on running these two (2) locomotives back-to-back I suggest speed-matching them in that configuration individually before consisting.
Have you done a break-in running of the locomotives in the direction you plan on running them?
On the unit you plan on running in "reverse" set the direction in JMRI under the "Basic" tab.
Before speed-matching any units, I allow them to run a minimum of 45-minutes in the direction they will be running.
When I switched DCC systems to NCE I found there was an overall speed difference between the Advanced Consisted locos and running them individually.
The decoders were all Digitrax DH166 series.
I contacted NCE and they advised me to set CV57=102 on all the decoders.
Since you are using Soundtraxx decoders I don't know if this is applicable.
If you are still having trouble with speed matching I suggest contacting the great folks at NCE and see if there is an issue with the way they handle consisting and Soundtraxx decoders.
Hope this helps.
"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"
Hello,
Although I've never had to resort to it, most decoders have a "reverse trim" option that allows modification of speed curves in relationship to direction.
CV 95 on a Tsunami2 decoder:
D0-D7: Reverse Trim Scalar 0 = Disabled 1 = Voltage ÷ 0.008 . . . 127 = Voltage ÷ 0.99 128 = Disabled 129 = Voltage × 1.09 . . . 255 = Voltage × 1.99
Additional Information Values from 0 to 255 may be entered into CV 95 to determine the scaling factor for the reverse drive voltage. Entering a value of 0 or 128 will disable the reverse trim scalar. Entering a value from 1 to 127 will decrease the reverse drive voltage by 0.008-0.99.
Entering a value from 129 to 255 will increase the reverse drive voltage by 1.09-1.99. Note: Bit 4 (STE) of CV 29 (Configuration Data 1) must be set to 1 to enable the reverse trim scaling factor in CV 95. Also, CV 25 cannot be set to either 1 or 0.
More here, page 27:
https://soundtraxx.com/content/Reference/Manuals/Tsunami2/tsu2_diesel_usersguide.pdf
Good Luck, Ed
My layout is strictly DC, not DCC, but I have found that if a train is fairly long (and heavy) multiple locos may be needed to move it up long grades, and have learned that most of those locomotives (usually regardless of type or size) will co-operate surprisingly well with one another.
If you're using multiple DC powered locos just for the sake of showing-off, with little need of power to pull a short train, you might find that some locos won't co-operate very well at all.
Wayne
Thank you, all. I will try the break-in run first; they have both been operated for short periods of time but never for a single time period of 45 minutes are more. After that I'll dig into the reverse trim settings, as it sounds like what I may need.
Just to close this out as "problem solved": the break-in run did the trick for one set of locos, and I did adjust the reverse trim on another set that was not resolved by doing a break-in run. Many thanks to those who responded!