# Power help



## JonScott (May 12, 2010)

Hello everyone,

I am in the process of building my first garden railway and over the course of the last month I have learned quite a bit but I'm still a little lost on what I should do for powering both my locomotive and rail. I have the Bachman spectrum 2-8-0 along with about 90' of Aristo-craft USA track, running in a 12'x40' area. From what I understand I can run DC, DCC or battery.


I understand DC but what I don't get is some folks say they run multible trains on one transformer, How exactly does this work? 

DCC seems to be the most appealing to me but my first year budget is fast becoming depleted! I'm also not sure what I would need to have say 3 loco's running?


Battery seems pretty appealing but I have no idea where to even start or if my loco will even accept a battery.

I really would appriciate any help or links to get me going!

Thanks,
John


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## chuck n (Jan 2, 2008)

John:

As a beginner, I would suggest that you get up an running with straight DC track power. Get your train running and once you have been running for a while and realize how much fun this hobby is, there will be time to decide on your ultimate power.

They all have their advantages and disadvantages. I have been running, inside and out (since 1983) since about 1980 on straight DC track power. I like it for my purposes. I have one battery/RC engine that I can take to other layouts that do not have track power. I'm about to convert another to battery/RC for the same reason. With both DC and DCC you have to keep the rails clean. My mainline is about 90' long. It is too short to run more than one train at a time. So, I don't worry about controlling more than one train at a time. I do have 2 passing sidings so I can have three trains out and switch off running them.


Another suggestion is to visit other garden railroads in you area and talk to the owners about the whys and wherefores of their power choices. I also suggest that you join a local garden railway club. They are a very good source for local information. If you tell us what part of the country you call home, someone will most likely provide you with local contacts. 


Chuck


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## toddalin (Jan 4, 2008)

Posted By JonScott on 12 May 2010 11:58 AM 
Hello everyone,



I understand DC but what I don't get is some folks say they run multible trains on one transformer, How exactly does this work? 

I really would appriciate any help or links to get me going!

Thanks,
John 



Even though the trains may be on the same or different loops of track, they are essentially traveling on the same track, electrically. When you control one, you control them all simultaneously. You can add electrial switches to the track sections (e.g., between two turn-outs) to turn those sections off, or give their control to a separate power pack, so you can park trains or control them independantly simultaneously.

If you want to control two trains, you really need a minimum of 3 amps. An MRC 6200 is about the minimum you would want to use, and this assumes relatively small trains without lighted coaches. If you get 10 amps, you're good for ~4 engines depending on if you want lighted coaches, etc.


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## jimtyp (Jan 2, 2008)

John, Welcome to MLS! 

Your question is the same one I faced and others too. To get started with: 
- DC - you need a power source and controller (dial of some sort that applies power to track) - these can be two components or one (controller is built in to power supply). You can run multiple trains on one transformer but they'd all run with the same power, and if they don't have the exact same motor, etc. one will eventually run into the slower one.
- DCC - you need a power source, and DCC system. Then a motor decoder for each locomotive. A lot of experts on MLS, for detailed info look at and post questions in the DCC forum here on MLS. To run multiple locos you switch between them, using the decoder address in each locomotive, with your DCC hand controller. You can apply power to each locomotive individually that way.
- Battery - there a lot of battery experts here on MLS - if you don't get the answers you are looking for post a question on the Battery Forum here on MLS. I'm not a battery guy but I believe you will need a wireless controller, battery pack (one or more), charger, then a decoder for each locomotive. There are advantages to battery, including not having to clean track, switches, and reverse loops.


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## JonScott (May 12, 2010)

Thanks for the quick replies and welcomes! Looks like DC is best for my budget. From poking around here I'm thinking at least 10 amps. Let me ask this, can I still use this if I move too DCC for say lighting or switches...etc? 

I am located in Westminster Colorado, dangerously close to Mizell!


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## chuck n (Jan 2, 2008)

10 amps will be fine for either straight DC or DCC. It will be overkill if you go for battery and R/C and only use it for lights and switches.


Make contact with the Denver Garden Railway Society. It was a great group when I lived in Denver (we moved to Virginia in 1993). The folks at Mizell or Caboose should be able to give you contact information. 


Unless you live is an open space with no plants there will always be track cleaning. With battery you just have to sweep it, Track power regardless of how it is used needs clean rails for good electrical contact. Stainless steel rails does require much less cleaning than does brass.

Chuck


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## jimtyp (Jan 2, 2008)

John, If you buy a separate power supply and controller (two components) you can re-use the power supply for DCC in the future, that is exactly what I did. It costs a little more up front but you save in the long run. 24volt with 10 amps is what I have for a power supply and I can run 3 trains at the same time, but keep in mind the amps used are dependent upon your locomotive. 

Yes, Mitzell is a dangerous place and so is Caboose Hobbies ;-) I know Caboose has all the major DCC manufacturers set up (for HO but concepts are identical to G) to show you how they work. I would bet Mitzell would have something also. DCC is a standard but then manufacturers have some different features to try and distinguish themselves, such as ease of use, how many functions you can control, etc.


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## lownote (Jan 3, 2008)

I started exactly like you a few years ago. I wanted to be able to run more than one train. I was very interested in doing it cheaply. I was never interested in battery power, for a variety of reasons, but don't worry, the battery guys will be along momentarily to tell you its the best way to go.


So I progressed like this 

1. Conventional DC. I started with some star set power packs, which kept quitting on me. So I got a meanwell 24 volt 10 amp power supply and an aristocraft ten amp throttle. To run multiple trains, I set up a passing siding and used LGB switch motors with the "EPL accessory switch" to cut power to the siding. That way I could park a train on the siding while another train ran by This is a very simple version of what's called "block control," where you divide the track into blocks and cut power to individual regions of track as you go along. 2. DC Power, with remote control. As I got a few more locos, I built a shed that the trains could be stored in and just roll right onto the track. To make that work, I bought some of Aristocraft's 75 mhz Train engineers receivers and a transmitter. I installed the decoders in the locos. By setting the 10 amp throttle to near full, I could put a constant 21 volts on the track, and control up to five locos individually. Fun!
2a. Then I wanted sound, so I went to QSI decoders and the "Airwire" throttle. It works a lot like the 75 mhz TE, except sound is built in and it was cheaper and you can do more with it. Why? Because it's DCC, except the signals are sent over the air. 
3. I figured out that if I went with DCC on the rails it would be cheaper overall, and maybe work better, and again I could do more. So I bit the bullet and bought a 10 amp DCC rig, which I have not regretted one bitIt would have been cheaper to go with DCC from the start, but it's hard to know that starting out. I still use the meanwell power supply, and the QSI decoders, and some of the 75 mhz decoders. So you could use DC power and block control, but wiring is a bit of a pain. You could use DC power and remote control, with either the aristo “revolution” system or the QSI/Gwire system, or Airwire.
Or you could use DCC. A cheaper way to get into DCC would be to buy a 5 amp system initially, and then upgrade to ten by adding a booster


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## JonScott (May 12, 2010)

Okay I'm still lost! I talked with Caboose hobbies and they recommended a Crest PS http://www.caboosehobbies.com/catalog/product_info.php?manufacturers_id=&products_id=14187 for DC use. Not quite 24v, but they do have a pretty limited selection. Could someone lay out exactly which brand PS and controller is best? If I do decide to go DCC straight off is there one package that has everything I need, Power Supply, decoder, etc... 
The selections seem so overwhelming, I can not for the life of me get my head around this! and I'm in the lighting business ... lol


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## Greg Elmassian (Jan 3, 2008)

Before I jump in, you really want to make a decision if you are going DC or DCC... 

Don't use anything lower than 24 volts for DCC, you lose about 6 volts from the transformer to the actual motor... and you will have top speed issues with some locos if your power supply is 22 volts. 

You mentioned budget... if you worry about budget, you need to consider whether you mean long term or short term. 

I'd do some more reading and decide where your future lies... 

Read the FAQs on my site and the power section... you have not mentioned battery power yet, which should also be considered. 

By the way, I run DCC... 

Regards, Greg


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## lownote (Jan 3, 2008)

Greg is right--if you want a lot of speed from you trains--for example, passenger runs at real-life speeds--then you want 24 volts. If you are less concerned with that, you might be able to get away with less.

I used this same MeanWell power supply, the S-320-24, when I was running both DC power and now with a DCC setup. It provides 24 volts and 12.5amps. 


Power Supply 

You can find them for less, sometimes under another brand name.

The Crest power supply is fine; as Greg mentioned, if your priority is running at higher speeds, 24 volts is better than 22 on a DCC rig. Voltage controls speed, but amperage determines how much current you can put on the track.


What do you imagine for this RR? If you imagine running mostly one train at a time, and modest lengths of 3-12 freight cars, at slower speed, you don't need a lot of amps or volts. If you imagine running, say, really long trains of lighted passenger cars up steep grades at crack express speeds, then you need more amperage and higher voltage. 


DC power is simple at the start, and cheap. For example you could just buy this unit rather than the crest:


MRC ten amp 


It has controller and power in one unit, and ten amps--perfect for DC, and you might never need more than that. If you decide to go with DCC later, you can still use the MRC power supply--just set it to full power and leave it that way. If I wanted to run DC, that's what I'd buy.


If you imagine running want to run multiple trains at once, and you want a high level of control over how the trains run, then you want DCC. If you decide to go with DCC, you could use this, the NCE five amp system, and if it turns out to be not enough amperage, upgrade to 10 amps by adding a "booster:" 


NCE 5 amp 

With the NCE system I just listed, you still need a power supply. Either the meanwell I listed or the MRC I just listed would be fine as a power supply with the NCE system. If you went with DCC, you would need to install a decoder in each loco.


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## Chucks_Trains (Jan 2, 2008)

Don't use anything lower than 24 volts for DCC, you lose about 6 volts from the transformer to the actual motor... and you will have top speed issues with some locos if your power supply is 22 volts. 


WOW!! So with DCC you have a 25% power drop? Where does all that power go?


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## Greg Elmassian (Jan 3, 2008)

Chuck, I was being conservative... often it's just 2 diode drops, so maybe 2 volts each time.. 

In DCC, the "booster" converts raw power (AC or DC) and a low voltage DCC signal into a full voltage DCC signal... since this is basically a big amplifier, so the "output transistors" give you a voltage drop from the input to the output. In NCE systems, fed DC as an input, the RMS DCC voltage output is 3 volts lower than the DC inputs. 

Now, in your loco, your maximum voltage to your motor is again from the output of the "output transistors", and furthermore, since DCC is not sensitive to the polarity of the rails, there is a full wave bridge rectifier on the track inputs. The combined voltage drops are usually between 1.5 and 3 volts, depending on the types of transistors used in the output stage, and what kind of "diodes" are used in the full wave bridge on the input. 

EVERY "decoder" has some voltage drop from the input to the motor, since the power goes through transistors somewhere. FETs can have lower drop. 

Have you ever measured the difference in voltage from the input on the rails to the motor output (you need a scope) on DCS? It's there too. 

This is why many people who go from DC to some sort of remote control often say "my trains run slower".... I have my system tuned to put 24 volts on the rails, and then I get no less than 21 volts at the motor.... even then certain locos run slower than prototype, like my Aristo E8's which cannot achieve passenger train top speeds (because they use the same gearing as the Aristo road diesels). 

Regards, Greg


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## George Schreyer (Jan 16, 2009)

DCC boosters regulate their own output, part of the drop is the regulator working at lighter loads. The booster drops about 4 volts, most can accept AC or DC input so that 1.5 volts of that is the internal bridge rectifier that is there to deal with AC. DC follows the same path and suffers the rectifier drop too. The rest is in the output switches. Once the DCC signal is applied to the track, it is delivered to the loco with some voltage drop in the rail/wiring. Then the decoder has to rectify it AGAIN, another 1.5 volts, and then there is some voltage drop in the motor driver switches. Decoder voltage drops are generally about 2 volts. 

It's not a big deal, you just have to budget for it. 

BTW, 24 volts is only necessary if you like to highball. A narrow gauge railway gets along just fine with 16 volts on the rails. I limit my outdoor railway to 22 volts to keep the maximum speeds down so that I don't fly off the track in the turns. I limit the track voltage on the indoor railway to 16 volts to maintain NG speeds.

see links for more info on the ups and downs of most power sources.. 

http://www.girr.org/girr/tips/tips5/power_tips.html 
http://www.girr.org/girr/tips/tips6/prime_power_tips.html


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## East Broad Top (Dec 29, 2007)

If you're running a 2-8-0 (which is a narrow gauge loco), then you needn't worry about concerns with top speeds. I run 14.8 volts worth of batteries in mine, and with a mere 12 volts going to the motor, it's "flying" around the railroad at around 30 scale mph--about twice that typical of narrow gauge locos. A 20 - 24-volt power supply will provide plenty of speed for your locos. Given your other space requirements and total track at the moment, you don't want to have your trains running very fast anyway, because they'll be looping the railroad every 20 seconds or so at high speeds. 

As for "which is best," that's a question for which there cannot be an answer. You mention running multiple trains, but one would assume you're going to be expanding your track in order to do so. 90' of track isn't going to build you a very large railroad at all. So, more track would be a must for multiple trains. Are you going to run them on separate loops, or are they going to be all on the same mainline? If they're on separate loops, that lends itself to "regular" DC operation quite well. You can get a power supply like Bridgewerks or some other brand that has multiple throttles, and run the output of each throttle to each separate loop. Aristo's trackside "Train Engineer" system would work well in that case, too. (Note, this is their "older" Train Engineer, as opposed to the "Revolution" Train Engineer that was just released last year.) 

Something like that will get you up and running the quickest, with the least amount of fuss. 

When you go DCC, R/C, or any of the "advanced" control systems, you open yourself up to a whole new world. Each locomotive you purchase must be modified with your chosen control system. How "easy" this is depends on a few things. First, the system you're installing; second, the locomotive you're installing it in; third, your comfort level when it comes to messing with electronics inside your locomotive. The trade-off is the increased functionality you get above what "standard" DC offers you. Independent control of the locomotives regardless of the track, sounds, lights, as many extra features as your chosen system allows. 

If I were to offer you advice, I'd recommend starting out with "standard" DC to get up and running. Buy the Crest power supply and a "trackside" Train Engineer controller. That'll get you going without having to rewire any locomotives. That one power supply should handle two separate loops without any trouble. (You would need a second trackside Train Engineer unit for the second loop.) It also gives you handheld remote control. (One remote will control both trackside units independently.) Then, I'd search out others in your area to see what they're running and how they're running it. That'll give you a chance to test-drive the various systems to see if you really have any need to use the higher functions, and if so, which one suits you the best. You can read volumes and volumes, but you really can't fully relate to it until you actually sit down and drive. Once you do that, you'll have a bit of better perspective from which to figure out what--specifically--you actually want to do. 

Later, 

K


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## Greg Elmassian (Jan 3, 2008)

I agree with what Kevin said, but don't buy the 22v crest supply. Buy something else if you think you want to go to DCC and don't want the possibility of buying a different supply. Also do not buy the Crest "Everest" supply, the 15 amp one, it has problems with premature shutdown on DCC and other systems. 

The meanwell has worked well for many people and is less expensive, and fan cooled with a better fan. 

Regards, Greg


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## JonScott (May 12, 2010)

Thanks again guys, I'm beginning to come round! 
With the amount of work I have left in the yard it seems best to go with DC and the MRC ten amp, the price is right and at this early stage it seems to be the least hassle. I have plenty of room to expand in the future and will look into more advanced power and control systems at that point. I have a feeling I will never really be finished ;-) 

John


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## lownote (Jan 3, 2008)

That sees like a good decision to me--that or as Kevin Strong suggested, the meanwell and the aristo trackside te would be good too. 

I really like the DCC setup a lot, but a lot of the time I'm just talking to friends and neighbors while a train goes around. DC is fine for a lot of what anyone wants from a train in the garden


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