Skip to main content

I have a friend who wants to run some older locos with AC (series wound) motors on DCC.    Does anyone have a wiring diagram for wiring the motor and what components such as a Bridge rectifier  you might need.

The standard DCC decoder puts out a DC supply to the motor, so wiring the motor for DC would be the same.

Original Post

Replies sorted oldest to newest

It's not necessarily a bad idea, and it's certainly been done before (see attached file.)  But Vernon's points are valid:  You will need to isolate the motor field from chassis ground.  That's probably the hardest part, because on some locos the field coil is really buried in the chassis.  And, you'll need a high-current decoder, I would say 3-4 amp rating at a minimum.  I know they exist in G scale, forget about using anything designed for HO scale.

While you're in there, you might also upgrade to shunted brushes with snubber capacitors.  Excessive sparking from the commutator and the resulting electrical noise might interfere with the DCC signal in the converted locos, and even others that are nearby on the track!  Supposedly that's one reason why back in 1993 Neil Young and Lionel took a different approach to TMCC signal propagation with ground planes, etc., instead of just adopting the then-new DCC protocol which transmitted through the rails.

Before you start, you should know that a 1950s toy train won't run like a scale model just because you convert it to DCC.  However, it sounds like an interesting project.  If you do this mod please post up some pics or video!

Attachments

Last edited by Ted S

Conversion of AC universal motors to DC operation comes up quite often. With the time honored conversion circuit that has been widely discussed,  AC universal motors will run quite nicely with direction determined by DC polarity. The caveats are the grounded to frame issue and the current requirements which tend to be higher than can motors. With a proper motor conversion, almost any control system with an adequate motor power level will operate a converted AC motor. With a large investment in earlier AC powered locos ( which many of us have), this is a reasonable approach to upgraded operation.

My friend says he has 40-50 locos which he wants to run.    

NCE makes a very nice decoder model # D408SR which is rated 4 amps continuous and 10 amps stall.    I have  used a lot of them in my 2 rail locos.    They also have an additional 6 output functions for various lights and stuff.    These are rock solid and hard to kill.

Soundtraxx has a 4400 series Tsunami decoder that is rated at 4 amps I think and has very nice sound and multiple function outputs.

Digitrax has a few rated at 3-6 amps but I don't know about sound on theirs.

@prrjim posted:

My friend says he has 40-50 locos which he wants to run.  

NCE makes a very nice decoder model # D408SR which is rated 4 amps continuous and 10 amps stall.    I have  used a lot of them in my 2 rail locos.    They also have an additional 6 output functions for various lights and stuff.    These are rock solid and hard to kill.

Soundtraxx has a 4400 series Tsunami decoder that is rated at 4 amps I think and has very nice sound and multiple function outputs.

Digitrax has a few rated at 3-6 amps but I don't know about sound on theirs.

Or put another way. What does a handful of TMCC powermasters cost and a CAB1 remote- to a control a layout of already conventional postwar trains? One powermaster per loop or specific section of control?

6-24130 http://www.lionel.com/products...powermaster-6-24130/ original MSRP $78.99 (Trainz has several used from $56)

CAB1 remote- $100 or less depending on deals

using any postwar transformer or power source, or a modern powerhouse brick  up to 180 Watt (10A)

VS

Opening each and every loco, installing decoders, then building out a high amperage capable DCC layout of boosters and power supplies?

A quick google:

nced408sr= $69.95 MSRP

TSU-4400=$205

DG383AR 3 Amp Mobile Decoder=$64

Times 40-50 locos- plus additional labor and supplies to wire up. Using an average price of $70 per loco times 45= $3150

Layout supply side of DCC

Power supply digitrax-ps2012e-20-amp-power-supply-12-to-23-vdc MSRP $236.00

Digitrax EVOX Evolution Express Advanced 5A/8A Starter Set, North American Version $366 to over $500+

Maybe it can be done cheaper or you use different components.

Last edited by Vernon Barry

NCE offers a 10 amp booster, and Digitrax offers 8 amp boosters.    They also offer lower powered ones.

With DCC you need one "command station" and as many boosters as you need to provide the power for your layout.      All the boosters have circuit breakers.    You can also put in circuit breaker boards that are faster acting than the boosters and divide the layout into "districts" which both protects the boosters, and does not shut down the whole layout when someone shorts out something during an op-session.

Why would this any more a bad idea than buying and installing a proprietary system that sometimes does not even offer receivers for locos?    Or a system with only one supplier who might go out of business?

If  you are willing to work on your locos and have some basic skills, you can do this.

Something like this is more for someone who wants to operate their trains and is not worried about collecting them or changing collector value.   

Can the TMCC power master and Cab1 control more than one loco on the same track?    This guy is not building a loop or 2 that are independent to run trains.    He is planning a model railroad and wants to control each loco independently so they can run on the same track with individual control.   Also think in terms of 6-8 people operating trains on the layout at the same time - 6-8 Cab1s.

I don't know anything about the system  you mention, but I did not notice any receivers in the locos.   How do you control them separately?

I'm sorry Vernon, I disagree.  With your suggestion, he would still be controlling the AC voltage to the track. Depending on the track layout and what the OP wants to do, controlling the voltage to the rails, even with a block system and walk-around control, isn't the same thing as truly independent control of each loco.

If your friend doesn't need wireless walk-around control nor independent whistle control, and is content to run no more than two locos at a time on the same main line, then there's an elegant solution that's robust, easy, and very low-cost.  But the description is too long to post here right now.

One more out-of-the-box suggestion: Powermasters are selling for about $60 each.  You can assign a unique ID to each and address up to nine of them with a CAB-1.  So you could buy several Powermasters, gut them(!), and put the circuitry in the tender shell(s)!  In this scenario, 18V would be on the track at all times.  ALL of the track power would flow from the track through the Powermaster circuitry before continuing to the motor, headlight, smoke unit, etc.  In this case, each loco would be individually addressable (but probably not in the way that Lionel intended!)

If you must have on-board whistle, then the Powermaster "guts" could go in a trailing boxcar or baggage car.  This "command receiver car" approach would actually save even more money, because then you wouldn't need one for each loco!  Just a wiring harness (tether) to connect to the boxcar.

There is no one "right" answer.  It depends on how many locos you need to run at once, will they be on the same mainline, how much time and money are you willing to spend, etc.

Last edited by Ted S

The cost works out to different effect for different people's situations. A lot of it depends on how large your locomotive fleet is and how large you expect to grow it, along with layout size. And, increasingly, whether or not you want to utilize a smartphone or tablet as a primary control device, plus interoperability with other systems and on other layouts.

Speaking only for myself, I only have MPC-era Lionel plus a couple of can-motor newer acquisitions, both of which are conventional. I was sidelined for the entire development of TMCC, DCS, and Legacy up until now with the transition from handheld remotes to the changeover to new WiFi+smart device controls. If I want to convert my fleet to command control, I have the possibility of choosing from any of the systems, TMCC probably being the easiest -- especially since there are already ERR systems with the necessary components for connecting to open-frame motors.

But personally, DCC holds more attraction because I can still find a system that uses a handheld remote control. (I work in enterprise-level tech, and I personally want to avoid the problems of limited support lifetimes, degrading battery life, and decreasing battery availability plus limited serviceability of "smart" devices. They're costly throwaways.)  There are few sound decoders that directly interface with 3-rail locomotives, but the continuing influx of small current-limiting and protection components is making it more feasible than ever to adapt and integrate DCC devices like Tsunami/Blunami, ESU Loksound, and others into my fleet. These threads are interesting to me as I look into the possibilities and learn from shared experiments.

@Ted S posted:
One more out-of-the-box suggestion: Powermasters are selling for about $60 each.  You can assign a unique ID to each and address up to nine of them with a CAB-1.  So you could buy several Powermasters, gut them(!), and put the circuitry in the tender shell(s)!  In this scenario,

Well, before Lionel pulled them from the parts listings, you could get LCRU2s for $35 with wiring harness......

And even with that source dried up, the bay has LCRU(2) with Railsounds 2.5 listed for $57!!!!!

LCRU2s by themselves for $60

Just saying- a lot more "tender friendly"

Attachments

Images (1)
  • mceclip0

Add Reply

Post

OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
800-980-OGRR (6477)
www.ogaugerr.com

×
×
×
×
Link copied to your clipboard.
×
×