(If this looks familiar, it’s because I also have it posted over in the “Layouts” forum.)
Hi Everyone!
I was wondering if you could help me out with a question. I just purchased a Stewart VO-660 switcher with a Digitrax DN143IP(?) installed into it. Is it fairly normal for Digitrax decoders to need the CV’s tweaked. It seems that there is no momentum and the speed increments are set at “14”. Even with the dial on the command station set at 50%, the VO-660 is still whippin’ around the track.
I also have a P2K S1 switcher that I installed a Lenz decoder in and it absolutely crawled from the getgo - no tweeking required. Is this just how Digitrax decoders are? Since I have a Bachmann EZC, I’ll have to find someone with a “programmable” DCC systerm in order to change the momentum and speed limits for achieve slow switching. No complaints. I was just curious if this was the case.
It depends on how the installer set the Digitrax decoder. Generally Digitrax DH140 series decoders come with reasonable speed setting values, but back EMF may be off.
The other thing is if the command station and the decoder are out of sync on speed steps, you can get the jerkey speed changes you mention. Just make sure the decoder and command station are both at 28 speed steps. Don’t know if you can change these settings with the Bachmann system, but this is what I would do on another system when I see this kind of behavoir.
Tom, it sounds like the decoder has been programmed already by the previous owner. It will probably be quicker to reset the thing back to factory default settings. Here is a link to the manual for the decoder that tells you how to do this.
Thanks, Joe. The Bachmann EZ Command is very limited what it can do and changing CVs is not one of them. I did inquire to the guy, who installed the decoder in the VO-660 for me, and did get a response back from him. He told me:
“I set CV54 so that you would have “yard Mode” available. If you activate Function 6 it will cut your speed in half.”
I should be able to do that on the Bachmann. I know that F10 turns the headlights on and off so I’ll see whether F6 helps out with the speed. According to the decoder info sheet, the momentum of the DN143IP is factory set at 000/x00. That would explain why it starts out so suddenly.
Standard settings for most decoders has no momentum. Isn’t the Bachmann system supposed to have some for of momentum built in to the throttle, since you can’t program the decoders for individual momentum?
Yes, you should be able to activate the switch speed mode. F6 is accessible from the Bachmann system. Although - I find with my DS4-4-1000 I don’t need it, it runs so well at the low end I can creep into a standng string of cars and couple up without moving any of them.
The only problem I’ve had with Digitrax decoders is that the torque compensation/back-emf defaults are not right for anythign I’ve installed them in so far (mostly Proto 2000, maybe the defaults work better with a BB Athearn) and I’ve had to tweak each and every one to get totally smooth operation. Unfortuately you have no way to adjust this stuff. Is there anyone near you who has a different system that can directly program CV’s? It’s sort of a trial and error process - Ops Mode programming comes in REALLY handy for this kind of thing.
I was able to cut my speed in 1/2 by pressing F6 on the command station, as the installer suggested. (It was even in the decoder info sheet, had I bothered to look.) My VO-660 now runs (crawls) like a REAL switcher, rather than a forumula one race car. Unfortunately, like the lights, I’ll have to re-engage F6 everytime I turn the command station back on to run the layout. Oh, well…one of the drawbacks of the Bachmann EZ Command system. But…a miniscule annoyance compared to a lot of things.