DCC amps question

I am about to take my first plunge into DCC on my own N scale layout (I have operated with DCC on several other layouts, but never installed it myself).I am considering purchasing MRC’s new Prodigy Advance. I am reading everything I can find on the system. Tony’s says that while the system is rated at 3.5 amp the system as it comes will crank out 2.0 - 2.5 amp max, and to achieve the rated 3.5 amp one will need to buy an alternate power supply. My layout has an 85’ main, just under 300’ total trackage, right now is running 5 total locos on tha layout at a time, but the eventuality is to be 10-12 loco’s on the layout at a time with a max of 7 actually operating at any given times. Here are my questions. 1) will the 2.0-2.5 amps run my needs (4-5 locos) now? 2) Will the 2.0-2.5 amps handlw my eventual needs (12 total max, 7 max running)? 3) Will the upgrade of 3.5 amps run my eventual needs? 4) Can one use multiple power packs in power districts with this system to generate more toal amps and use the one operating systems? Some of you DCC geniuses help me out here. This is not my forte, though I am finding it quite interesting to learn. Thanx

Ron

Ron,

It seems to me that with your current investment in your layout and the size (amount of track) you should “spring” for a 5amp system like NCE, Lenz or Digitrax. I don’t know much about the NEW Prodigy but I know the other systems mentioned would handle your needs for many years to come.

With the number of locomotives you hope to eventually be running at once, start with a better and more powerful system than the Prodigy. As jwmurrayjr wrote, consider an NCE, Lenz, or Digitrax 5 Amp system. Spend a little extra money now so you don’t have to just throw away your cheap system and purchase a totally new one later.

I agree. With the size of your layout and the number of locos you plan to run, a 5 amp system from Digitrax, Lenz or NCE seems like the way to go. Your intial investment would be a bit more but it would serve you better in the long run.
Have Fun,
Tom Watkins

I had planned on the jDigitrax Super Empire Builder before the Prodigy Advance came along. I had thought I might save $50 if the MRC system would suit my needs, but that is why I am gathering all the info I can first. Sounds here like I had better go back to my Digitrax plan.

Ron

Although you might be able to get by with one power booster, for better short management you will probably want to divide you layout up into at least two power districts, each with their own power booster.

For this reason, I recommend the smaller 3 - 3.5 amp power supplies because they are cheaper, and the more amps you put through the rails, the more potential damage (melted ties or loco parts) can occur with a bad short.

I do agree with the recommendation to go with a more robust system than MRC, but if you can save money on boosters do so.

The basic guideline I recommended in my DCC clinic at the Seattle National last July (from 11 years of experience using DCC) is to prefer more low amp power districts to a few high amp ones. 5 amps (HO and N) is overkill, and if you have 8-10 amps per district, IMO you’re crazy.


FWIW, you can get a copy of my DCC Clinic on video at:

http://model-trains-video.com

Agree with Jim, you will definatly need a 5 amp supply system.

Here is a followup question to your response. Someone on here told me that with Digitrax (and maybe other systems too) one could use one 5 amp power source and use a Digitrax accessory (I don’t remember the exact name or part #) to insulate and divide the layout into power districts for short management. If I remember correctly, when I looked into this I believed I could divide my 80’ main into 4 districts easily with the same 5 amp supply. Is this correct, or am I dreaming?

Ron

You can do that with ANY system. Digitrax makes the item, so does NCE, and Tony’s, among others. They are electronic circuit breakers. But you don;t get 5 amps multiplied times the power districts, not from a single 5 amp booster. What you DO get by dividing your layout up is short circuit protection. Boosters already do that, but if there is a short and only 1 booster, your whole railroad comes to a stop. Now, if your operation includes operting helpers pushing live coal loads up steep grades and the power just got off like that, you’ll have a nice mess to clean up.
You cna also set these electronic circuit breakers to trip at lower current levels. If each section you have one connected to can handle at most 3 or 4 locomotives, you can set the trip current way down for extra protection.
Others have scoffed at me for this, but I have seen the pictures posted that show the damage caused by a RESISTIVE short, 5 or 8 amps at 14 volts is a LOT of power. Sure, adequate bus wires and making sure the ‘quarter test’ works is great, and SHOULD be enough, since you aren’t supposed to press the quarter down, just set it on the rails, but I still won;t run a straight 8 amp booster to my rails without dividing it up into power districts with electronic breakers set at somethign less than the full 8 amps.
Which brings up another point - if you can find a proper transformer, 8 amp boosters are usually only a few dollars more than the 5 amp versions, a good bargain for 50% more capacity. Maybe 5 amps isn’t enough, but 10 amps is overkill, so get an 8 amp booster and use electronic circuit breakers and make multiple power districts. One 8 amp booster and a breaker will probably cost less than two 5 amp boosters.

–Randy

Thanks for the input, Randy, I’ll take all of this into consideration as I progress.

Ron

if you take a short amout of time to draw your layout with some measurements and operating wishes you could send it in to Digitrax and they will give you a detailed list of items needed to fulfill your dreams.

I recently purchased a MRC Prodigy Advance from Tony’s, and I am extremely happy with it. I bought the additional power supply as well so that I can power it to the full 3.5 amps. It has been very easy to set up and use. I have read that this is not the system to use for a large layout, but other than the cost for additional boosters and accessories is there any reason for all of the negative press. I know that the original Prodigy DCC system was not very good, but this one seems to correct most of the previous versions issues. What am I missing?

Also, I am interested in knowing if the 3.5 amps will power 12 locos with a max of 7 running, since I already have purchased it.

You don’t say what scale. That’s .5 amp per running loco, in N that should be plenty. In HO - if some of them are newer Stewarts and Proto2K with nice low current draw, then yeah, it should be enough. But if you are loading up on the sound-equipped stuff, no, 3.5 amps won’t be enough to run 7 at a time. You’ll need an additional booster at some point. MRC has an 8-amp one that will work fine with the Prodigy Advance.

–Randy

I don’t have DCC yet on my layout, and am trying to get as much information as I can.
This discussion has been that if you spend big bucks on a super system, it solves all your problems. Mr Fugate has 11 years experience with DCC and says go with several small systems and everybody else want people to use power right from the wall, something is really wrong here. I think Mr.Fugates experience should mean something and everyone else wants to make plastic toast.

You will note that I agree with Mr. Fugate in the need for protection, not just feeding a gazillion amps into the track. I just prefer to go about it using electronic circuit breakers such as the ones sold by Tony’s Train Exchange insteadof light bulbs.
You will also not that I have been nothign but a proponent of starting small and expanding as your layout grows (unless you ALREADY have a huge layout and just want to convert to DCC). This is EXACTLY the route I am taking, and why I am such a strong proponent of Digitrax. I currently have a Zephyr, and until a month or so ago I had nothign but a loop of Bachmann EZ Track to test my equipment on. I am now in the midst of constructing an 8 x12 HO layout that will later become a part of a lager layout running around the walls of my basement. The more I grow, the greater the opportunity for additional operators,a nd the need for more power capacity to operate the expected number of locos, and as I reach the each milestone I will add the additional boosters and circuit protection needed to support the expected level of operation. I envision the ‘completed’ layout supporting 6-8 operators, with double- and triple-headed locos, ranging from the latest Stewart to stock-motored blue box Athearn. And some sound-equipped units as well. Definitely something that will require more than 5 amps total power. But do I need that today? Nope, but I can easily add it when I do.

–Randy

I have a 14’ x 17’ layout that operates on DC right now and am thinking of switching to DCC , the most engines that can run on it are 5 or 6. I think an MRC system would handle me for now. And I can’t expand until 2008 when my youngest goes to college. I can then get another room that is 16’x22’.

While using Tony’s circuit breakers is certainly one option to DCC short management, they are pricey compared to the 1156 tail light bulbs. Tony’s solution is about $30 per train block, but the bulbs cost about $1 each per train block.

On my Siskiyou Line, I have about 30 train blocks (360 feet of main, so that’s an average of one train block every 12 feet), which would be $900 using a Tony’s solution, but a mere $30 using the bulbs.

Granted the bulbs are not quite as fancy as the electronic circuit protection, but the bulbs perform their function quite well in my experience. I’ve been using the bulbs since 2000 on the Siskiyou Line, and they are marvelous! You can see a demo of the bulbs in action if you go to this URL:


http://mymemoirs.net/preview.php

Watch the second video clip down, the one on the short management demonstration.

While the bulbs may not be as sophisticated, they are more than adequate for the needs of most DCC layouts, so do not write them off just because they are simpler. Sometimes, simpler is more elegant!