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How many DCC boosters are needed for HO scale layout?

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Posted by Tophias on Monday, July 29, 2024 7:26 PM

Nile, thnx for the follow up. Many posters never get around to giving a final solution to their problem. Many of us here appreciate your final comments.

Regards, Chris 

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Posted by NILE on Monday, July 29, 2024 4:52 PM

I have replaced the DB150 with a new DCS 210+ Command Station, and so far.  I have had no problems.  The other day I ran three trains with eight engines (at least 2 of them with sound) and everything worked great.  Maybe the DB150 was getting old or maybe it was never made to handle that much at one time, either way things are work now.

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Posted by ALEXANDER WOOD on Sunday, July 7, 2024 12:34 PM

NILE
Well I've been using the layout a lot more and still having the same problems.  I tried to buy a DSC210 but apperently bought the wrong one, and that stalled my power booster and district efforts for a while.  Is it possible the DB150 is just getting old?  Should I get a new command station?  Or is just a combination of volts and amps, and I'm pushing to demand for to many amps.

There's a couple of different issues here. One is the command station, then the boosters. The DB150 is designed as a booster, but has limited command station functionality (no programming track and only 22 slots).

Unless you have abnormally power hungry HO scale locomotives, you shouldn't need more than 3A for 3 operators each running a two-unit consist. The size of the layout doesn't matter, you can run DCC power over 100' if you have heavy enough wiring, idle current can add up if you have a lot of idling sound locomotives or resistor wheelsets for signals.

You could get a RRampMeter, which might help you figure out if you have locomotives that are drawing a lot of current, either due to an older design, or maintenance problems that can be fixed, or if your system can't put out enough current.

Considering that most Digitrax systems are 5-8A, a single command station/booster should be more than adequate for what you are doing with some PSXX breakers to create power districts for short management.

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Posted by YoHo1975 on Thursday, July 4, 2024 6:53 PM

Well, he likely doesn't need a 5 amp booster. He might need a second booster, but I suspect 5 is overkill. But you really can't buy smaller anymore.That's just what is available now. I think the fact that by post 3 circuit breakers had been brought up and that the op eventually came back and said that hadn't occured to him is key. The fact that he'd have 10 amps available is irrelevant. But having a proper safe layout that won't melt engines is key. And that is true even if he just had a 5 amp booster and nothing else.

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Posted by richhotrain on Thursday, July 4, 2024 5:43 PM

This thread is coming up on 3 years old, but let's recall the OP's layout design and his original question.

He has a fairly large layout with the main portion in one room and a large staging area in a second room. His question is whether it makes sense to install a second 5 amp booster.

Now, in the various replies, no one suggested adding a second 5 amp booster to provide 10 amps on a single bus. The predominant suggestion has been to add a second booster and create two separate booster districts, one in the main layout room and the other in the staging area room, each on its own separate bus.

Rich

 

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Posted by MisterBeasley on Thursday, July 4, 2024 1:47 PM

reasearchhound

This thread has boggled my mind on two levels;1) the complexity of some of the replies and 2) the depth of knowledge many of you have on this subject.
Couldn't anyone just say; "Put in two 5amp boosters and you'll be golden."?

Golden, as in the color of toast?

We are trying to provide the advice necessary to have higher powered layout without danger.  I started DCC with a 5 amp Lenz system powered with an old train transformer of about an amp and a half.  It was fine for running one or two locomotives, but it ran out of power when I added a couple of old incandescent passenger coaches.  I replaced the old transformer with a modern 5 amp supply and my power problems were solved.

My additions since then have involved splitting the layout with breakers.  I've kept the original 5 amps and it's been fine.  I have 4 of the PSX breakers plus two older auto-reverse sections, which also function as breakers.

And feeders.  We haven't even discussed feeders.  Mine are every 2 or 3 feet.  A good bus-and-feeder system is imperative to maintaining power in a larger layout.  Even soldering every rail joint isn't as good as a good cover bus with lots of feeders.

It takes an iron man to play with a toy iron horse. 

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Posted by YoHo1975 on Thursday, July 4, 2024 1:23 PM

2 5 amp boosters with no circuit breakers is asking to melt your locomotives any time they short. In general, you should never be able to pull more than about 2amps before a circuit breaker trips on an HO layout. If you are running Southern PAcific style consists with 7 locomotives, then maybe you have to risk higher current. But I would increase the trip current as minimal as I could. Say in .25 amp increments. 

 

I'm not sure about the poster discussing the rules around throttle to base station lengths. I've used NCE, MRC and TCS and the lengths you need to run before the throttle bus gets wonky are incredibly long. 

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Posted by richhotrain on Thursday, July 4, 2024 1:23 PM

reasearchhound

Couldn't anyone just say; "Put in two 5amp boosters and you'll be golden."?

It's been said - - long ago.
 
October 16, 2021 to be exact.
 
Rich

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Posted by reasearchhound on Thursday, July 4, 2024 11:30 AM

This thread has boggled my mind on two levels;1) the complexity of some of the replies and 2) the depth of knowledge many of you have on this subject.
Couldn't anyone just say; "Put in two 5amp boosters and you'll be golden."?

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Posted by YoHo1975 on Thursday, July 4, 2024 2:06 AM

I agree, I wouldn't choose a 10 amp booster.

At my club, we're using TCS the base station is a built in 5 amp booster and then we have a B-106 6 amp booster. Our layout is roughly twice the size of the OP's and honestly. If we were only running trains on the mains, we could probably work all but the busiest run days on the 6 amp booster. With both, we can regularly handle half a dozen engineers and then another 8 or so locomotives idling about the layout. We use 4 PSX boards for the mains and another 7 for various yards, the roundhouse, a seperate loop called the "shortline" And then a single auto-reverser for the reversing loop.

All PSXs are set to 2 amps. On our previous layout we didn't use Circuit breakers. The gentlemen that built it didn't know about them or didn't care to use them and just had many boosters. Those were old MRC 3.5Amp boosters which is still too much in my opinion and once MRC went to 5 amp boosters we started melting locomotives that decided to short. So, to me Circuit Breakers are an absolute must. 

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Posted by richhotrain on Monday, July 1, 2024 4:19 PM

know2go

Hi,

The need for boosters should not be defined by the size of the layout, but by what will be happening on it.

For a similar size layout I use a single NCE 10 Amp Power Booster, and it will easily satisfy 100 locos plus thousands of accessories. No need to make it more complex. One time investment will ease multiple upcomng years of additions and upgrades without worry.

Hope this helps!

 

 

It's been difficult to get the OP to manage this thread.

As for the current suggestion to install a 10 amp booster on an HO scale layout, that seems a bit scary to me. Plus, he may by now have purchased a 5 amp system, so why not just add a second 5 amp booster?

Rich

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Posted by know2go on Monday, July 1, 2024 4:01 PM

Hi,

The need for boosters should not be defined by the size of the layout, but by what will be happening on it.

For a similar size layout I use a single NCE 10 Amp Power Booster, and it will easily satisfy 100 locos plus thousands of accessories. No need to make it more complex. One time investment will ease multiple upcomng years of additions and upgrades without worry.

Hope this helps!

 

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Posted by richhotrain on Wednesday, May 15, 2024 5:44 PM

NILE, I am an NCE user, so I know very little about Digitrax products.

Did you ever purchase a second booster?

What is your current setup regarding booster districts, power districts, circuit breakers and auto-reversers? Please bring us up-to-date on your electronics and wiring protocols. Still have the two room setup?

You ought to consider purchasing a DCC Specialties RRampMeter to measure voltage and amps across your layout.

Rich

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Posted by MisterBeasley on Wednesday, May 15, 2024 1:37 PM

If you're still running the layout with just the original 5-amp base station, have you subdivided the track sections and wiring for power districts, but kept them wired together?  I didn't do that, and ended up regretting it.  If you prepare everything for power districts, it becomes easy to add breakers to subdivide everything later, or even do that piecemeal by adding one breaker-protected district at a time.

I too have the DCC Specialties quad circuit breaker board.  I found that once I bought it, the job of splitting up the layout into power districts only took an afternoon, because the layout was a already divided appropriately and all I needed was the breakers.

It takes an iron man to play with a toy iron horse. 

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Posted by gregc on Wednesday, May 15, 2024 7:02 AM

NILE
I have a log of engines and a good number of them have sound.  I have noticed that these engines draw more power and on my last layout I was limited to five engines at a time.  Bascially two trains, one with two engines and one with three.  If I ran any more than that the DCC system would short out.

NILE
Those layouts had around 30 feet of main line double track main line. My goal is to get enough power to the rails so 1-3 operators can run 2 multi engine trains.

NILE
Well I've been using the layout a lot more and still having the same problems.

if each engine draws ~1/3 amp, 3 operators running 2 2 engine trains is 12 engines and ~4 amps.  the DB150 is rated at 5 amp.   perhaps the unused engines with sound are exceeding the limit.

our club has 2 (~7 scale mile) mainlines and often has opens houses with 3 multiple engine trains running on each.   the club has three 8 amp boosters.   the mainlines run roughly parallel to one another and are divided into 3 sections each with a booster.

you might just need a booster that powers half your layout, i believe the club has DB210 Boosters

greg - Philadelphia & Reading / Reading

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Posted by NILE on Tuesday, May 14, 2024 7:48 PM

Well I've been using the layout a lot more and still having the same problems.  I tried to buy a DSC210 but apperently bought the wrong one, and that stalled my power booster and district efforts for a while.  Is it possible the DB150 is just getting old?  Should I get a new command station?  Or is just a combination of volts and amps, and I'm pushing to demand for to many amps.

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Posted by richhotrain on Thursday, November 11, 2021 2:40 PM

gmpullman
 

Booster District is dictated by the power requirements for a given number of current-consuming locomotives and rolling stock.

A Power District would further divide the output of that booster to particular segments of track primarily determined by "If I have a short here, do I want the inconvenience of the trains stopping over there".

Imagine if your house only had one main breaker, for everything. By dividing up the circuits if you plug in an old, faulty toaster in the kitchen the lights upstairs in the bedroom don't go out.

I used to have my power districts grouped by areas on the layout. After a while I found this to be rather inconvenient as a derailment on a yard track would shut down all the track in that area.

Now I have just that yard on one breaker and each of the main line tracks passing through are on their own breakers. Now when that yard engine runs a switch or a car derails, both the main line tracks can continue running.

I believe that Ed makes an important distinction here between a "booster district" and a "power district". 

A booster district monitors the amount of current draw (amps) from all of the running locomotives in that district even if a booster district is further subdivided into power districts. Amps in excess of the booster's capacity will shut down the booster to protect itself from damage.

A power district protects the district that it directly controls by shutting down the district if a short circuit occurs within that district.

Early on in this thread, I suggested that the fact that the layout will be set up in two different rooms may be reason enough to divide the layout into two booster districts, one booster in each room. That will give NILE better control over the layout. I stand by that suggestion. The second booster is to assure better control over two physically separate areas. Then, he can add however many power districts he wants within each booster district.

Rich

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Posted by John-NYBW on Thursday, November 11, 2021 1:54 PM

Take into account how many engines are going to be in each district at one time. I divided my mainline into two roughly equal power districts but after looking at it, I realized the second district will not have nearly as many locos sitting idle as the first district which has the main yard, engine terminal, roundhouse, and five track passenger station. I rerouted the wiring for the roundhouse to the second district to balance the load but I also have an on/off switch to the roundhouse so it's not drawing power except when engines are being moved in and out. 

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Posted by riogrande5761 on Thursday, November 11, 2021 6:42 AM

The length of a power district can be limited by how long a run can be without significant loss of power of that length/distance from the booster.  I assume you will be running a power bus with feeders to the rails along the way.  If using 14 AWG bus wire, for example, the longest run would need to be limited to 50 feet.

https://dccwiki.com/Wire_Sizes_and_Spacing

From the wiki:

According the Big Book of DCC by Digitrax, runs up to 100 feet are possible with 12AWG wire, and 50 feet with 14AWG. This is for one leg; in theory it is possible to have a 100-foot run (14AWG) with the booster in the middle (50 feet on each side). Don't skimp on wiring, plan for future power needs.

For the layout represented in the track plan, I plan to start with 1 Command Station/booster and employ 4 PSX1 breakers/power districts.  I can add a 2nd booster if needed later.  One for each yard, one for the mainline and one for the branchline.

Rio Grande.  The Action Road  - Focus 1977-1983

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Posted by gmpullman on Thursday, November 11, 2021 12:00 AM

NILE
How long should a power district be for a double main line? I had thought you needed a different booster for each district, I see that is not the case.

Booster District is dictated by the power requirements for a given number of current-consuming locomotives and rolling stock.

A Power District would further divide the output of that booster to particular segments of track primarily determined by "If I have a short here, do I want the inconvenience of the trains stopping over there".

Imagine if your house only had one main breaker, for everything. By dividing up the circuits if you plug in an old, faulty toaster in the kitchen the lights upstairs in the bedroom don't go out.

I used to have my power districts grouped by areas on the layout. After a while I found this to be rather inconvenient as a derailment on a yard track would shut down all the track in that area.

Now I have just that yard on one breaker and each of the main line tracks passing through are on their own breakers. Now when that yard engine runs a switch or a car derails, both the main line tracks can continue running.

NILE
How long should a power district be for a double main line?

My double track main is probably 140 feet or so. Each track is divided into roughly half that length so there is a total of four breakers, track one east, track one west — track two east, track two west. 

The length of the track in each power district is only limited by the robustness of your supply feeders and power bus, up to a point. Most of us won't reach that point as voltage and signal loss won't degrade very much until you get into those huge modular setups found at some shows and such.

Good Luck, Ed

 

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Posted by NILE on Wednesday, November 10, 2021 8:54 PM

Duplicate post

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Posted by NILE on Wednesday, November 10, 2021 8:43 PM
Thanks for all the comments and suggestions, honestly it has been a lot to digest. As for not engaging as much, my apologies but life is busy. How long should a power district be for a double main line? I had thought you needed a different booster for each district, I see that is not the case. I have built three DCC layouts prior to this house, and I never used power districts before. I didn’t think a one room layout needed it. Those layouts had around 30 feet of main line double track main line. My goal is to get enough power to the rails so 1-3 operators can run 2 multi engine trains.
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Posted by richhotrain on Sunday, October 24, 2021 3:49 PM

Dave N

Rich,

This might be over his head...lots of different aswers. I'm having a hard time keeping it straight myself!!!

Dave 

You raise a good point, Dave. I'd like to see NILE reply even if it is only to ask questions about the replies from others to his initial question. I always like to see an OP "manage" his own thread so that there is a better dialog than just a bunch of replies going all over the place.

Rich

 

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Posted by Dave N on Sunday, October 24, 2021 3:41 PM

Rich,

This might be over his head...lots of different aswers. I'm having a hard time keeping it straight myself!!!

Dave

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Posted by richhotrain on Sunday, October 24, 2021 3:07 PM

I'm surprised that the OP has not responded since his initial post.

Rich

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Posted by jjdamnit on Sunday, October 24, 2021 2:50 PM

Hello All,

NILE
How many DCC boosters are needed for HO scale layout?

To answer your question there are three (3) things to consider:

  1. The number of locomotives and cars drawing power; sound cars, lighted cars etc. which translates into Amperage, which relates to the number of boosters.
  2. Signal transmission- -This relates to the size of the layout and the number of cabs (throttles) in use, which also includes wireless control via "radio" or WiFi.
  3. Power management- -Simply hooking up five (5) 10 Amp boosters to power the entire pike with 50 Amps can be potentially dangerous.
      • Consider the breaker panel in your house. The panel might be receiving 100 Amps but circuit breakers divide this into 15- or 20-Amp breakers (circuits).

Now, a little math...

NILE
I have a log (lot?) of engines and a good number of them have sound.
I have noticed that these engines draw more power and on my last layout I was limited to five engines at a time.
Bascially (SIC) two trains, one with two engines and one with three. If I ran any more than that the DCC system would short out.
(Paragraph breaks added for clarity.)

To determine how many boosters (power sources) you require, you need to calculate the Maximum Amperage Draw required (with approximately 10% to 20% "Headroom").

NILE
I also have a couple of big steam engines, with sound and smoke. Those seem to draw even more power.

With sound-equipped motive power there is also a "start-up" spike in amperage.

Think of it this way...

When your refrigerator "starts" there is a brief moment, in its power cycle, when the amperage "spikes" over what the running amperage is rated at. This "spike" can be accommodated within the calculated "Headroom".

Now for the big math...

Let's presume that each locomotive draws 1 amp. If you have a 10 amp system you can simultaneously run 10 individual locomotives- -minus any other "powered" cars. (A consist draws the amperage of the total number of units in the consist.)

OK, so now we've calculated the approximate total amperage draw of the number of locomotives being used, this gives an approximation of power sources "boosters" needed.

Now let's look at the physical size of the layout and the signal path or "signal run" from the cabs (throttles) to the command station/boosters. 

For many, not familiar with electronics and signal flow, the concept of the output of the command station/power source (booster) to the bus wire or track, contains both electronic signals- -power source and signal packets

That's what those "jumper" wires do to connect the two separate units in the same enclosure to provide the DCC signal to the bus/track.

For traditional, tethered cabs (throttles) the placement of powered UTPs are required to maintain the strength of the signal to the command station/power source (booster).

Each manufacturer has its own Recommended Practices on placement.

Wireless; Radio and/or WiFi systems should be factored into the signal load.

As I mentioned above, yes...you can power the entire pike with one 50 amp booster (power source), but that would be unsafe.

Even with a 5 amp system power management or "Districts" are recommended.

NILE
...so the booster would also be the auto reverser.

If you dedicate a booster as an ARU, it only powers/protects that individual reversed section. If this is a small loop perhaps a single standalone ARU, downstream of the booster, could be a possible solution.

Take a look at your track plan, consider which "blocks" or "districts" would benefit from circuit protection.

On my 4' X 8' pike there are five (5) power districts protected by four (4) single circuit breakers and a single standalone ARU and ECB combination.

There is a myriad of possibilities/solutions given your particular situation.

Understanding the challenges of the components will hopefully help you achieve your goal.

We can only suggest.

Ultimately, it's up to you to find a solution to your goal.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by MisterBeasley on Sunday, October 17, 2021 11:13 AM

Please don't hook up a big booster directly to the track.  That puts a lot of available power which could concentrate in one spot and do some damage.  Instead, heed the advice to use individual circuit breakers to protect smaller power districts.

Think about this early on so you can isolate layout sections with insulators or gaps.

My layout was in a 24x24 foot room and I was working on the trackage on the third wall.  I had a lot of track and about a hundred square feet of layout.  I have about 20 powered engines, mostly with sound, but I typically only ran about 3 at a time.  I have a 5-amp Lenz system, which seems to handle all the DCC with no trouble.

It takes an iron man to play with a toy iron horse. 

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Posted by gregc on Sunday, October 17, 2021 7:53 AM

hopefully summarizing

it's not the number of boosters but the current capacity of the boosters.   one 10A booster instead of 2 5A boosters

the density of trains in a section of the layout determines the # and sizes of the power districts.   if a circuit breaker is set to 2A, the power district should be sized to handle some # of trains such that there total current is < 2A.

and finally, you could have 6 or 7 power districts all supplied by a single 10A booster.   they are not all likely to draw 2A at the same time (e.g. 14A).

if you have a command-station/booster rated at 5A you may need to add a 5A booster.   3 power districts connected to one and 4 less heavily used power districts connected to the other

greg - Philadelphia & Reading / Reading

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Posted by gmpullman on Saturday, October 16, 2021 8:25 PM

NILE
I would like to hear anyone's oppinion on this?

Hello,

I didn't see it mentioned what the output capacity is of your present command station/booster. It seems you already know that it overloads when you are running five + locomotives so there certainly looks like there is at least one additional booster in your future.

Dedication another booster just for a reverse "loop" (or wye) seems wasteful to me especially when you can get an auto reverser that will also act as an electronic circuit breaker would suffice. Plus, a staging yard wouldn't normally see all that much current draw unless you have lighted passenger cars plus idling locomotives.

Kill switches aren't a bad idea for a staging/storage yard for the little cost/effort it is to install them.

Probably more importantly is to have your layout divided into segments protected by circuit breakers. One PSX quad could be wired as two pairs and you can divide the main line into two power districts then feed other sidings and yards off the other two and the wye on its own reverser/breaker.

If you're switching or placing locomotives on the track in a yard or engine terminal you don't want the main line shutting down becase of a brief short or running through a closed switch.

I, too, have many sound locomotives and lots of lighted passenger cars. I have three Digitrax boosters (8 amp!) each divided into four power districts. Still, with four trains running, sometimes a total of 12 to 15 engines, and several tracks full of idling locomotives each booster never sees more than about 2 - 3 amps of current draw.

I'd say get one booster, one auto reverser and one quad breaker and see if that takes care of your needs. You can always add another booster at a later date.

https://dccwiki.com/Power_District

 

Lastspikemike
For DCC you just wire all the power districts together, effectively bypassing the insulated blocks.

Not sure I'm following this. A booster doesn't define a "power district" but a circuit breaker protecting a length of track, defined by the location of an insulated joint on each rail, does. One booster may feed any practical number of breakers. The breakers will help avoid the unnecessary shutting down of trains running in other areas of the layout.

Good Luck, Ed

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