Hi Søren,

When I have had this situation I have walked through all of the CVs that I can access and compared the settings, making them match. I am not 100% sure that just matching the parameters at that level will fix this problem however and the factory decoders are locked and impossible to fix when the base software is not correct.

If you were to replace both decoders, build a project for them, and load that program onto both decoders, you could ensure that they are identical. But short of that I would be interested to hear other options for fixing this from the collective forum wisdom.

Locking the factory decoders was one of the worst decisions I have seen them make. Considering the price of current models they should have the best decoders available, not crippled, unfixable junk. I guess that means ESU and that is not going to happen.

Hi Søren

I may be totally off topic but seems to me the adjustment is not difficult doing so:
- make available a rail loop, free of other locos
- create a double traction
- make sure both locos have the same acceleration curve (linear, standard exponential, exponential,...)
- adjust first the speed of each loco by adjusting CV 5 on one of the locos
- once the speed is the same on both locos (your case), start adjusting the acceleration delay using CV 3
- when finished, adjust the braking delay using CV4

Notes:
- of course, you pick one of the locos as your reference and adjust the other one
- as Jim already said, CVs are dependent on the motor type, on the transmission (gear ratio), on decoder type mSD2, mSD3, etc. A simple duplication won't do in all cases.
- once both locos, when placed at each end of the loop, when subjected to various command using the double traction command behave similarly, you may couple them.
- double or multiple traction are not fit for use with isolated section from signals (risk that one loco stops while the rear loco keeps on pushing and may burn its motor. This is reserved to manual control or train software like Rocrail.

Here is a video on this subject


Rocrail note: there is a possibility to bring multiple locos to form a large multiple traction train and then start using the traction as a single loco and then , uncouple locos and start using them individually. Of course all this in complete automation but only when previously all their CVs have been adjusted as per above

Cheers
Jean

I suspect that these locos originally came with the original msd decoders, and the repaired one now has an msd/3 decoder, which will have different drive characteristics. It shouldn't be impossible to speed match them, just take some time.

Hi Søren


With a CS2, the edition screen is easy to reach
- select the loco
- press the wrench key
- select the tab motor to edit the needed variables
You obtain a screen like this (sorry in German here.
The frames zones show you where to edit the max speed, acceleration delay and braking delay
Don't forget to load into the loco by pressing the key with a downwards arrow to a locomotive




Cheers
Jean

Thank you very much Jean for clarifying this.

Did a quick test and just using the same parameters gave a good initial result. Now I just need to fine tune the parameters a bit more.

With regards to adjusting maximum speed what is the general advice? To max the speed at say 140 or keep it at default (which in this case is 180)?

Cheers
Søren

Hi All

Thank you for your kind help so far. I will test the various parameters over the weekend to further fine tune the two locos thanks to your helpful advice.

Jean, look forward to hearing from you when you have had time to complete your tests.

Søren

Soren, I would let the faster one do the pulling, what I have done with mine, I turn the acceleration and braking delay off, so you don't get the push pull situation with both locos.

John