DCC Noobie Question: Loco Terminal

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Lazy Daydreamer
Hi all,

Since I'm just getting my toes wet with planning/setting-up DCC, I have a question that may seem a bit "d'uh":

I'm putting a small engine terminal on my layout and want to do some 'hostling' operations, which I never was able to easily do in DC.

According to Tonys Train Exchange website, a 5-amp booster can 'run' between 10 and 15 locos, probably 1/2 that number for sound-equipped. Does every loco parked in an engine terminal constitute a "running" loco if the tracks are powered, even though they aren't moving? (After all, power is being applied to the decoders.)


Fun Lover
Sorta, a parked loco doesn't pull as much current. But I wouldn't worry with your new unit. If a 2.5a Zephyr can pull 10 trains half of which are sound, then you have nothing to worry about with 20 sitting idle.

I double dog dare you to overload that new unit of yours. You just won't do it with your layout. You couldn't if you wanted to.
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Lazy Daydreamer
I sure hope your right Chip! I just remember seeing so many boosters around Jim Brewer's layout that I thought maybe my single unit might not be able to handle it. I remember somebody across the street telling me that I should have a minimum of 5 amps if I want to run sound locos.

(Funny how many urban legends are sprouting up about DCC, ha!)

Steve B

Listen Ken, my friend brought his cheap Bachmann DCC set here a few week's back and we had running round the track these loco's all at once, if the Bachmann unit can do it (the transformer was getting a bit hot though) your new one will Eat more loco's than this no problem
1, BLI C30-7 with sound
2. LL GP20 with sound
3. Bachmann Class 20 with Loksound
4. 2 x LL P2K SD60's no sound
5. Bachmann Class 25 no sound
6. Atlas gold MP15DC with sound


In Training Down Under.
Ken, I have a 5amp Lenz DCC system and have had everything I own running

8 locos all with sound (don't try this on your own!!):D and 8 lighted passenger cars. The system didn't miss a beat, the transformer is an old washing machine power supply;)


grande man

Bonafied Grande Nut
Hi Ken. We run our Super Chief on an old MRC 3.5 amp power supply. I just counted 20 locomotives on the layout, 4 of them sound equipped, and we haven't had any problems. We rarely have over 5 or 6 locos running at any time, most are in staging "waiting their turn". :)
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My Digtrax Zephyr with a Roco 2.67 A power supply is sufficient for running up to 4 P2K SD9's and two SW1200's with loads and 4 SD45T-2's running light. (all at once).
What I can't do, however, is programming Lenz 1025 decoders...
No problem programming Digitrax, Uhlenbrock etc., but the Lenz decoders require more power: only when I borrowed a 5 amp power supply, I could program my Lenz decoders.




Lazy Daydreamer
Thanks for the replies, everyone! Looks like amperage - or should I say the lack thereof - won't be a problem. Now all I gotta do is the 'RTFM' routine.:D

I'm doing all of my testing and learning on a simple, separate loop track so I'll know that everything works properly before I attempt to do this on the layout itself [where a whole different set of problems might be introduced]


Fun Lover
Thanks for the replies, everyone! Looks like amperage - or should I say the lack thereof - won't be a problem. Now all I gotta do is the 'RTFM' routine.:D

I'm doing all of my testing and learning on a simple, separate loop track so I'll know that everything works properly before I attempt to do this on the layout itself [where a whole different set of problems might be introduced]

I dunno....with my Zephyr it was just a matter of taking the two wires off my MRC and connecting them to the Zephyr. You have your DT400 so you should just be able to start running. You can always take the wires back off and hook the DC back.

grande man

Bonafied Grande Nut
Ken, I'm sure you know that most folks run buss wires under the layout and attach feeders from there to the track every few feet. I don't know how your layout is currently wired, but could you just wire buss wires into the current block feed switches for a simple conversion? I bet you could be up and running very quickly and still have the capability to kill power to any block if you needed to (analog loco, etc). For full DCC, just turn all the block switches on. A "quarter trick" test of each block would tell if you needed to add any additional feeders.

If you're already finished with the wiring, scratch all of that...:D


Lazy Daydreamer
Are we having fun yet?

...well, almost!

Chip/Eric - I believe my layout is ready to accommodate DCC; I have 14awg buss wires with feeders every 5-6 feet. But that's really not the issue.

My problem is, I'm still really "wet behind the ears" on using the technology. I want to continue practicing all the regular tasks - programming a decoder, acquiring a loco, operating in radio mode - until I reach the point where I can do it in my sleep. [Currently, whenever I come back to the system after being away for more than an hour, I have to fumble with the settings and glance at the manual to see what I forgot to do. ]

This way, when I finally plug it into the layout, if I have issues then I'll know immediately that the problem is with the layout track/wiring and not the Digitrax hardware.


Coal Shoveler
Locos sitting on the storage tracks will draw some power, especially if their lights are on. You can figure out how much of a draw by counting up all the milliamps of the lit bulbs.

Not sure how much power a sound loco draws; I assume there is some in order for it to make noises while they're idling away....



Ken: I agree with all that the standing locos just aren't a problem. The amount of current they are using is negligible. Lighted passenger cars will draw a good bit, but still not enough to worry about. I have 19 locos and one lit passenger sitting on the layout at all times and all but two locos have sound.

Layouts that have so many boosters are really installed for seperate power districts more so than for additional current supply.

I'm not sure where the current values are coming from that you read on the forums, unless they are based mostly on the open frame or early can motors and are using stall motor values. (Heck, how many locos are going to be stalled at once or how often and how long would you have even one. :rolleyes: ) I have never drawn the amounts that have been posted. I have a Tony's panel meter that measures the total track current and I back its measurement with a digital meter.

Some may frown, but I would bet you will be able to run 8-10 sound units (probably more) and several parked with no problem. As mentioned, you may experience a lot of heat on the heat sinks of the command station when running that many, but a fan out of an old computer blowing on it will take care of that. Don't worry if you should get to many...you won't hurt it if you do draw more than it will provide. It will simply shut-down, cool off, and be ready for reset when you lighten the current load.


Central Indiana & Ohio RR
Bad news. I had 21 engines running on the layout, 2 DB100 boosters (5amp each) and with running about 4 trains at a time (3 engines in most consists), I started having issues with over aperage. I never had the issue before, but when I asked around and my DCC guru all said I needed more AMPS. I only had 2 sound locos too.
My layout is large and I was going to purchase additional boosters now that we are having ops sessions, but this led to a quicker purchase of them. Much sooner then I hoped to.

What is worrysome is I don't have the engine terminal hooked up yet, so I will have an additional load for it. I am assuming I will need a booster just for it too.

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