You should do some speed matching with the engines coupled together and with a train behind them. That will be different from just the two engines. I would imagine the lead engine will always appear to run faster, and if uncoupled from the second engine, will just run away because the second engine is pulling a train.
Also, remember that if you have a fleet of identical engines, the DCC settings won't all be the same.
It takes an iron man to play with a toy iron horse.
John,
If you want to really fine-tune the speed curve for each locomotive you can always implement speed tables - i.e. CV67-CV94. That said, if you get "close enough" with just adjusting CVs 2, 5 & 6 - that should be good enough.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Well, after further testing, I now have the following settings for CV3, CV4, CV5 and CV6: 25, 20,160,48, for the Genesis Unit. Bowser unit is still 20,20,255,88.
Very different speed curve for the Genesis unit relative to Bowser. Not bad, just different. I like speed and the Genesis 2.0 units will roll a freight train.
The engines are matched very well on the low end between speed steps 4 (of 28) and 9 or 10. At 14 they are close but the Bowser starts to pull away slightly, and at 28 the Genesis unit seems almost even.
Since most of the time I will be operating between speed step 10 and 22 or so, I may try a couple more minor adjustments but they are actually getting close now. I just don't want them fighting too much and prematurely wearing wheel plating off--especially in any kind of emergency stop when cat jumps on layout. Also, I want them smoothly accelerating and decelerating together. After setting the CV 3 and 4 to 25 and 20 respectively, the 25 helps to slow the fast start of the Genesis unit just a bit till the Bowser gets rolling, and the 20 helps the Genesis unit to slow to a complete stop in about the same time as the Bowser.
It has taken me almost 4 hours of adjusting and testing to get them running as closely together as they are.
If there is a better way or if adjusting PWM will help, someone please let me know. Thank you.
John
PS It seemed that at any minimum voltage setting at or above 1 that the Genesis units were starting just too fast.
If I can get them dialed in correctly, these power sets could operate together for years.
I'm new to trying to speed match diesels in dcc, using just the 28 speed steps, on an NCE Powercab system:
My son has two of the Genesis SD90MAC-H engines, and I will have a larger fleet of Bowser SD40-2's once they are all here (most -2's on hand are plain dc right now but some do have dcc/sound). We now have some longer freight trains that will actually require two diesels to work together, so it makes sense to speed match the Genesis (Tsunami) units with the Bowser (Loksound 5) units.
To complicate matters, Athearn does NOT state dcc default settings in the manual, because it is written for more than one engine. The Bowser settings for Loksound 5 are CV2 (min voltage)=1, CV3 (acceleration time)=20, CV4 (deceleration time)=20, CV5 max voltage = 255, CV6 (medium voltage) = 88.
The Bowser units run extremely well at slow speed, run slower at most speed steps, and are slower at the top end, with nice smooth accel/decel, too. The Genesis units are racehorses by comparison, and clearly have NO accel/decel time, so I set them to match the Bowser at 20 (after playing with other settings). I lowered min voltage on the Athearn units to 0 because they move at speed step 1 and the Bower doesn't move till speed step 2 (which I apparently cannot find any adjustment that will start them moving at 1). I lowered (Athearn) max voltage to 190 and medium voltage to 60. This all was after 2 hours of playing around with them trying to get them to match.
So after 2 hours I have adjusted the Athearn settings to max voltage 190, medium voltage 60, accel/decel time 20 each, and min voltage 0. They will run together now, but I think I can still make some minor adjustments. As speed is increased to step 28 the Bowser unit starts to pull away slightly, but at slow speed the Genesis may still be a little faster.
I'm trying to get them to match as evenly as possible at all speed steps.
Is there something I am missing? If I adjust PWM will that make a difference in speed? Does it sound to you folks like I'm on the right track?
Also, the newest Loksound 5 Bowser units are just slightly different from the earlier Loksound units, and dcc settings are different. They DO run together, but not quite as well as I'd like. I would really like to get the Loksound 5 units moving at speed step 1, but have been unable to accomplish that. If I could, they would better match the earlier Loksound Bowser versions (and the Genesis units too)--all of which actually start creeping at speed step 1.
Thank you all.