Un-MUing an Advanced Consist on Digitrax

[Paul Cutler III]

Folks,
My club has a Digitrax-powered layout. One of our new members is also a member of an NCE-powered club. He routinely MU's his locos at the NCE club, then brings them over to our club, sometimes to run singly. The only trick is neither one of us can figure out how to un-MU his locos on our Digitrax system. Allow me to explain:

Digitrax uses what is called "Universal Consisting" where all MU info is kept on the command station. One selects the "lead" loco address (which doesn't even need to be a real loco) and adds "trailing" units to it. When a command is sent to the "lead" loco, the command station then relays it to all "trailing" locos as if it were the lead. This only applies to speed and direction. Function commands are not relayed to the trailing units. This is simple and easy (one doesn't have to program function outputs to not be on when MU'd unless you want all the horns to blow at once), but limited (one must know the "lead" loco address).

Also related, Digitrax has two forms of addresses: 2-digit and 4-digit. They are kept in different CV's, and CV29 must be set to choose one or the other. 2-digit addresses go from 00 to 128. 4-digit addresses go from 0129 to 9983.

NCE (and Lenz) uses what is called "Advanced Consisting" where all MU info is kept in each mobile decoder. This is done by programming a 2-digit address into each decoder (up to 128 because it's hex) and telling it to respond to that 2-digit number. This "consist address" then becomes the MU number the locos run on. This means that one can select any loco in the MU without knowing the first one and allows individual function control when MU'd (but it can force one to do so).

Also related, NCE (and Lenz) has only one form of addresses: 4-digit. It goes from "0000" to "9999" (AFAIK). NCE does not use 2-digit loco addresses because that's what they use for the MU addresses.

When our new member brings his NCE-MU'd locos over to our club, we can run them with the 2-digit DCC consist address. But when he or I go to un-MU them, we can't get them to. He has to take them back to his other club, un-MU them, then bring them back over.

So does anyone know how to un-MU advanced consists on a Digitrax system? Thanks!

[bnsf971]

Un-MUing is simple.
Call up the address, then using ops mode, set cv19 to 0.
I don't know how many times I've had to do this on my home Digitrax layout after running trains on the club NCE layout.

[Paul Cutler III]

Ah, thanks! I'll have to write this down and tape it to our programming cart at the club.

[grahamline]

Tell us more about this programming cart?

[Paul Cutler III]

The club's programming cart is an old jewelry display glass box (without the glass) mounted on caster wheels. We've mounted a new table top and added shelves and drawers inside holding a computer, plus a DCS200 DCC "brain", a programming track booster, a PR3, a QSI, and a LokSound programmer. We also have an MRC Tech III DC throttlepack. There's a flatscreen monitor on top of the table top along with a length of test track. The test track measures loco drawbar force with a spring scale in 1/4oz. increments. It also checks for wheel gauge, wheel flange depth, width/height of all rolling stock, coupler operation and coupler height (all locos and cars must pass basic standards to be registered on our layout).

Next to the monitor is a selector switch to choose which programming option you want (Run, Prog. via DCS200, PR3, QSI and LokSound) and includes the DC analog option as well.

I looked around on my PC, but all I have are old pics from 7 or more years ago. I know I have better ones around, I just have to find them.

[wsor]

One can also go to the Digitrax programming track and read what the consist address is, CV19. Dial up that number to run the consist on the Digitrax layout. NCE seems to assign random consist address numbers, but their system handles it fine.

I have a number of advanced consists set up, using Digitrax command stations and CV19. The lead unit gets addressed 1-128, and any units that you want to run in the opposite direction (back-to-back units, for example), get consist address plus 128 set in CV19. That sets the decoder to run the other direction. Setting up consists like this helps with slot conservation, and makes it easier for people who aren't tech-savvy. Dial up one number, and the consist goes.

[Paul Cutler III]

wsor,
At our club, we tend to just use "Basic" consisting if someone's running a big set of locos (making them all the same address and using CV29 to reverse direction of travel). All our locos have 3x5" index cards that go with them along with a 2.5x2.5" clear plastic pocket taped to it. When someone makes a Basic consist, they put a note in the pocket saying what address the loco has.

We usually only do this for our Open House, where guys are running long trains for hours at a time. We've had situations where a loco has dropped out of MU. If you're not paying attention, you can easily get flat spots on a dragging loco. Only 1 or 2 guys have experimented with CV19 consisting, AFAIK.

[jonklein611]

What about normal consisting? (At least on Digitrax, Dial up lead loco, dial up other loco, MU, wash rinse repeat)

[wsor]

CV 19 advanced consisting is decoder based, so if the command station gets stupid, the MU that the command station set up can fail, and goofy things happen. CV 19 consists keep working. If you go to other layouts that use a different system, the CV 19 consist will work there as well.

The only time I flattened wheels was when I had 2 P2K GP60s set up in a consist, then added a Atlas Trainman GP39-2 to the middle. Ran it around for a half hour or so, then came to the realization the GP39-2 wasn't responding. Open the hatch on the hood, and then I remembered I had taken the decoder out to place in something else. I was looking at an empty 8-pin plug.

[Paul Cutler III]

wsor,
Ouchie!