Bachmann Online Forum

Discussion Boards => Large => Topic started by: AVM on March 16, 2007, 08:07:20 PM

Title: DCC Conversion
Post by: AVM on March 16, 2007, 08:07:20 PM
Can a Bachmann Anniversary 4-6-0 Steam Loco be Converted to DCC
Title: Re: DCC Conversion
Post by: the Bach-man on March 16, 2007, 10:41:04 PM
Dear AVM,
Yes, as can any locomotive. You must isolate the motor and attach it only to the decoder. Make sure you get a Large Scale decoder.
Have fun!
the Bach-man
Title: Re: DCC Conversion
Post by: Jim Banner on March 16, 2007, 10:47:29 PM
Yes.

But it is more than just a plug-n-play job.  You will have to trace the wiring to be sure which leads come from the power pickups, which come from the motor, which from the lights and so on.  Not as hard as it sounds, but it does require opening up the locomotive.  If you make notes and keep track of the screws, reassembly will be relatively easy.  The bottom of an egg carton can be used to keep the screws in groups and can be labelled with a ball point pen.

I feel it is a good idea to measure the current draw of YOUR locomotive before selecting a decoder for it.  One way is to place your locomotive on a piece of tack and put a brick or two in front of it.  Connect your track, your dc power pack and your ammeter all in series then slowly turn up the pack and watch the current.  The maximum current, just before the wheels slip, is an indication of the maximum operating current.  (If the locomotive moves the bricks, add more bricks.)

After taking the locomotive apart, you can measure the motor stall current.  Set your power pack to about 18 volts (or whatever track voltage you plan to use) then measure the current as above except hold the motor from turning.  Many decoders have two current ratings, the smaller one is for operating current and the larger one for stall current.  If the decoder of your choice does not list stall current, you can estimate it as 50% higher than operating current.  Make sure you have an adequate rating for both currents.  If the operating current rating is inadequate, your locomotive may stop from time to time to cool off.  This is most likely to happen if you run it with heavy loads or up steep grades or on hot days.  If the stall current rating is inadequate, then the decoder will fail sooner or later.

If all of that sounds too complicated, talk to your supplier for a recommendation.  He will be happy to sell you a decoder with lots of excess capacity.  It will cost a bit more than one more closely rated to your actual load, but you can consider it cheap insurance.

Decoders normally come with instructions for installation.  If you need more help, there are a number of us who regularly read this board and are willing to help.
Title: Re: DCC Conversion
Post by: AVM on March 16, 2007, 11:38:53 PM
Thanks Bach-man and Jim, that was very helpful!
I think I'll have a DCC specialist in Oregon do it for me.  But at least I know its possible before I talk to him about it.

Thanks again,

AVM