Power District & DCC

Ok, I got the full scoop about DCC works and how to wire it all up. Amoung my readings and research I have only one question the remains. Please read the following scenerio so you’ll understand when I ask my question.

I get a 5amp DCC system for my 13X8 layout and say each DCC equipped loco that also has sound takes 1 amp each to run. That would make the max amount of loco’s I can run on my layout 4-5.

My question is, can I add another booster for my whole layout to have a total of 10amps, or do I have to section off my layout into power districts where one half is powered by a 5amp booster and the other half is powered by a 5amp booster???

If that’s the case and I have 2 trains with 3 engines each, doesn’t that mean that those two trains can never occupy the same half side of the layout cause all six engines on the same side would be pulling more amps than the booster can handle???

My basic question is, can I have more than one booster powering my whole layout and if so, what gage wire then do I run for my main power bus and feeder wires???

Thanks.

that’s correct , although your assumption of 1 amp per loco is probably high if you’re running recently made models

you have to make districts

to avoid this you divide the layout into a larger number of ‘blocks’ and use something like a digitrax pm42 to split the power output from the booster .

yes , and you want pretty hefty wire for the bus 12 or 14 awg , and smaller for the feeders i think around 18-20

My $.02, after purchasing a PM-42 I would look at Tonys Train Exchange. this is an easier system to use.
I am using 4 boosters with 4 districts off each plus 4 auto reverse sections. Your caoncept is fine our Canadian friend has it nailed. The other thing is to MAKE SURE the only thing running off your boosters are trains. Ran a 2nd bus for turnouts and one foe accessory wires (lights, signlas etc.)

My starting layout is going to be no bigger than 14X8 with room in the center for two people to stand in. I’m going to have two main lines so me and another person can operate at least two trains at once, 4-5 track wide railyard, the layout is a decent size but not that big. Is it really going to be necessary for me with that kind of layout to have at least 2 power districts which requires 2 boosters and then additional boosters on top of that if to run accessory items like switch, lights, etc???

And why can’t you have two boosters supplying a total of 10 amps to your whole layout?? Your engine is only going to pull the amount of ampage it needs to run it anyway, right??
The increase in ampage from 5 to 10 using two boosters I wouldn’t think would be any different than using a 5 OR an 8 amp booster, no??

I thought DCC and these boosters were more powerful than that. Seems like you have to have all this expensive hardware and wiring just to run a small-medium size layout and only have 4-5 engines running at the same between time for just two people, and power your turnouts and other accessories…???
Those boosters aren’t cheap at 2-300 bucks a pop.

If I’m averaging too high that one DCC equipped engine with sound pulls 1 amp, then how much ampage does todays DCC equipped with sound engines pull??

That’s a very good question. I had 3 sound plus 3 non-sounds locos running all at the same time on my 2.5 amp Zephyr. In the latest MR they reviewed the Proto2000 sound-equipped SW-8 and stalled it onl dew 0.43 amp. That’s about 0.25 amp higher than I measured on my P2K S-1, which should have a similar motor in it. My Stewart DS4-4-1000 only draws 0.15 amps (non-sound) so I’d guess it would also be under 0.5 amps with a sound decoder in it.
You can’t just add the amps, they have to be insulated power disctricts. This is why you need to put some thougth into the division. FOr example. I have a 2-track main. I would make each main a different power dostrict - it is unlikely that every running train would be on the same main going the same way, rather some trains will be on the East main and some on the West main.

–Randy

I have an Atlas system (2.5 amps) and I can run 3 to 4 trains without any problem (HO). I do use a separate power supply for all accessories. The Commander only powers the trains. No power districts of course (wouldn’t be a bad idea - 2 or 3.)

If you get a 5 amp system you’ll probably have enough power unless your planning a pretty large layout. Or you could get an 8 or 10 amp system and add power districts.

I hear ya rrinker. Claycts’s basically uses a booster for running trains and a booster for switches accessories, wired seperately. Does that mean you always have to use two seperate throttles…one for the trains and one for switches/accessories??? Everyone operating on the layout has to use two throttles to control each??? That don’t seem very user friendly and ease of use.

I’m willing to use my DCC system to only power and operate the trains, having a seperate power source for the switches/accessories using toggle switches you manualy switch by hand, but I’m sure they all don’t require another 5amp booster costing 2-300 bucks just to power them. How many amps does a turnout switch pull to operate??? Like .10 or something??? What can I use as a power source for switches and accessories if it’s not recommended to use the same booster you run your trains with??

I’ve got a Lenz 100 system with 5-amp capacity. I’ve had 5 or 6 locomotives all running at once, and I don’t think I’m close to running out of juice. The value called “stall current” is the most the locomotive can draw, if you’re sitting there holding its wheels so it can’t turn them. Typically, the real current draw is less than half that.

I only run trains on the DCC system. Turnouts are all powered separately, and I run them from toggle switches on a control panel. I also run my turntable, signals and accessory lighting from separate power supplies. The ability to control your turnouts from the throttle is nice if you are far from your control panel area, but I find it hard enough to keep two trains running on the same track without having to go off and address turnouts, throw them and then return to my locomotives. Other modellers really want to flip their turnouts from the DCC hand-held, but that’s a matter of personal preference.

The only non-locomotive things that will be drawing DCC power are my passenger car and caboose interior lights, and the occasionally-on mini video camera in the front of the subway train.

For your purposes, 5 amps will go a long, long way.

Ok MisterBeasley, then what do you use as your other power source for your turnouts, signals, turntable, etc???

I have an old transformer from Lionel. It is older than anything I remember as a kid, so I really and truly think it was probably build in the late 40’s or early 50’s, in the Truman administration. That’s the power supply for my DCC system, and for the incandescent lights on AC. I’ve still got my original cheapo train power-pack from the early 60’s (Kennedy administration) that I use to power the signal and subway illumination LEDs (DC), the turntable (DC) and the turnouts (AC, but converted to DC by the capacitive discharge circuit.)

No, they are all tied together. There can only be one command station, the rest are all boosters which slave off the signle command station and simply provide power to each district. If you are goign to run turnouts with stationary decoders, it’s always a good idea to have them run off a seperate power district (at the very least) or a different booster - if they simply run off local track power and you run into a switch witht he points set wrong and cause a short - well, if the stationary decoder draws local track power, it won’t have any power and you won’t be able to throw the switch to clear the short - Catch-22!
How much power depends on the kinf of switch machines you use. Tortoise only draw about 15 ma, that’s 0.015 amp! 100 of them is only 1.5 amps. The stationary decoders themselves draw a bit of power, but even so, a full 5 amp booster could easily run several hundred. I’m thinking of possibly adding a booster to my Zephyr and using the 2.5 amps of the Zephyr to run stationary decoders - although my latest idea using the R

My post is as Randy stated. They are all tied into Loconet and handel 850 ft of track so needed the punch to carry that big an area. The object of the districts is to keep from taking down the whole thing at one time with a short. Also you can find the problem vis isolation.
After buting a PM42 as the district breaker I recommend Tonys PSfour and PS rev they are much better. We orderd all we needed today along with edge connectors for the totrise machine so we do not have to solder anything.
When runnig the secodary bus you DO NOT need #12 awg, #14 or #16 is plenty. ALSO do not forget a ground bus to tie all the distrcis together with the booster. I am using #10 awg Solid for that job. Could have used #12 but the larger wire, less resistance, better trip on the breaker.
Take Care
George P.

something i just thought of…

when using a power manager like the digitrax pm42 (or tony’s etc) if you have a 5 amp booster and divide it into 4 sections , does each section only get 1.25 amps , or does it get as much of the 5 amps as it needs as long as the total doesn’t exceed 5 amps ?

I use a PM42 and it seems to me that each district gets what it needs with the “overload/short circuit” protection taking care of that business.
BTW, so far I’m very happy with the PM42.

Each section gets as many amps as you configure th PM42 for, so long as the total does not exceed 5 amps.

–Randy

If you like to tinker you can make a nice power source from an old (or new…they don’t cost much) PC power supply. It will supply plenty of power at 3, 5 & 12 VDC.

http://www.trainweb.org/silversanjuan/Page3/Page16.html

If you’re interested be sure to check ot the “original link” on the lower right of the page.

I use a Toy’s Trains Volt/Amp meter on my layout.
I usually run 3 Mountain F7s, 2 Stewart S-8’s and a Bachman 0-6-0 switcher concurrently. I also have 18 Tortise wired to the track via switch-It’s.
I have never seen this entire group pull in excess of 1.2 Amps.
I am using a 5 amp DCC system and 4 power disctricts protected by a Tony’s 4-breaker .

Sounds very similar to my layout, except mine’s 11x14 and has a short, 7-track yard. Otherwise, almost exactly the same.

I use a Digitrax Super Chief with no additional boosters, but I do have a PM42 to divide the Chief’s output into four power districts:

  1. Main #1 and all it’s spurs/sidings
  2. Main #2 and all it’s spurs/sidings
  3. Yard
  4. DS54’s/Tortoises for the entire layout

Having these four power districts is probably overkill, but considering the overall cost and complexity of building the entire layout, it wasn’t more than a nit.

That would be a question for an Electrical Engineer, which I am not. But I’ve always been under the impression that connecting the outputs of two power sources together is generally a Bad Thing.

[quote]
QUOTE: Originally posted by Lord_Beelzebub
I thought DCC and these boosters were more powerful than that. Seems like you have to have all this expensive hardware and

Thank you everyone for your replies and thank you Stevert for breaking it down for me and compairing it to yours so i understand things better.

I saw above turnout motors hardly draw any power to operate and I’m pretty sure my layout isn’t going to have no more than about 15 of them, I don’t plan on doing much lighting cause I’m not going to be running my layout in the dark or near dark situations. The most loco’s I’d have on the track would be 5 or 6 readily accessible for operation, but they all won’t be running at the same time. 3 or 4 would, but most likely be if I had them in a ‘consist’.

So it seems a 5amp booster will be more than enough for my layout, I just should be wise and make power districts using a PM42 which seperates the power of my booster amoung the districts to ensure a more relyable layout.

That’s what it seems you all are telling me, and if that’s correct, I’m all clear and I fully understand how to wire it all up.

Thanks everyone !

One last question, if I use the PM42 and wire for 4 sub districts, I have two operators and 2 trains end up on the same track, can the PM42 tell that more power is being consumed from that one track because of the two trains being on it at the same time and devert more power to that sub district to compensate so there is enough power???

No, there is no way to dynamically allocate power. When you configure each section of the PM42 for trip current, that’s it.
I don’t think you’ll have problems, unless you are running all old Athearns and so forth - meaning back before the gold-sided motor. I’ve had 8 locos running on my 2.5 amp Zephyr and could have had more going except with only 1 throttle it was tough keeping them from colliding. I had 6 going with 4 of them having sound. So if you set each PM42 section for 2-2.5 amps, each district should be fine. If you power the stationary decoders and urnouts from one of the PM42 sections, that one only needs to be at 1 amp or so (1.5 might be the lowest setting, I didn’t look in the manual).

–Randy