A-B-A install

[uncljoe]

Have Key PA  A-B-A that I would like to install DCC I ,do I keep all the units with the same ID number (as I will be operating as single unit)
What is the correct thing to do ?
Regards
 UJ

[bobthebear]

That's what I do. Don't forget to reverse direction of 2nd A unit!
Bob.

[djconway]

If you are going to wire them all together, make removable jumpers between units.  You never know when you will need to work on one of the units. Even real RRs found that the draw bar connected A-B sets needed to be broken apart from tine to time. 

I have several A-B-A and A-B-B-A sets, each unit has its own decoder (only 0ne of the units "needs" to have sound.  This allow for finer speed matching and I find smoother operation.

[nscalbitz]

Have Key PA  A-B-A that I would like to install DCC I ,do I keep all the units with the same ID number (as I will be operating as single unit)
What is the correct thing to do ?
Regards
 UJ

I'm not sure that's technically the right thing to do.
Every decoder/ unit should be unique; then consist them per prototype practice, which is using the Main A unit number (OR anything for you that is realistic ##) to all- like giving pseudonym to the 'trailing' units.

This way in use you 'address' the consist code- individual decoders keep their internal characteristics as necessary (speed variation/ lights/ direction etc).
d

[peteski]

I recommend reading https://dccwiki.com/MU_consisting and https://tonystrains.com/complete-guide-to-consisting/ .
In the end, it is really up to you to choose the one which works best for you.

The above articles do not cover the "poor-man's consist" (mentioned here) using singe decoder and running all 3 motors from it (I wouldn't recommend it).

[mmyers]

There are several ways to achieve what you want. Peteski has already listed links to explain them. I do recommend a decoder for each unit. You will be much happier with the results. If sound is in the picture there really is no need to have sound in each unit but that's up to you and your budget.

Martin Myers

[uncljoe]

To all who replied ,a BIG Thank you 
Semper Fi
 Joe

[nickelplate759]

That's what I do. Don't forget to reverse direction of 2nd A unit!
Bob.

Me too.  In my case, all 3 units have the same road number anyway, and always run together as a single "locomotive" so why not?   If you plan to mix-and-match units, rather than treat them as a single multi-part locomotive, then consisting is probably a better choice.