Selecting a DCC "Set"
Compare Various DCC Set Categories:
The
selection of DCC set is probably the most important choice you need
to make.
While command stations and throttles are not interchangeable between manufacturers,
the NMRA standards assure that conforming products are compatible at the track.
In other words, you may run any conforming manufacturer’s products with
any other’s. However, once you have selected a set, you need
to work within that manufacturer’s product line or those designed to work
with that product line - frequently these products are identified by the “throttle
network” or
“cab bus” identifier, such as Digitrax’ LocoNet or
Lenz’
XpressNET. So, let’s get started selecting a set for
you. The first question is:
How Many Amps do I Need?
While this may be confusing, I’ll try to take some of the mystery
out of it. The length of your track is not important in this selection,
assuming it is properly wired. What matters is how much power you will be
USING on the layout at once. I’ll go through an exercise for HO to
show you how to get there. For N or Z, just halve the numbers. For S or
O, I’d double them. For G, you’ll need at least 10 amps, so
start there!
One side note, the term BOOSTER sometimes confuses folks. They do NOT make the
power travel further, as CB radio boosters do. Think of them as power packs from
the DC days. The term comes from the architecture of DCC systems. While frequently
they are now integrated with the command station,previously, they were sold as
a separate box. What they do is take power from the transformer and use it to
BOOST the computer level data coming from the command station to an adequate
level to power the track. If you need more power, you can split your layout into
districts (think about this when you are designing) and put one booster’s
output on one district and another’s on the other.
Calculate Your Power Needs
In HO, I budget 1/2 amp for every loco you plan to have running at the
same time. Budget 1 amp for every Broadway Limited loco. The budget for
lighted cars is 1/10 amp. Each turnout which will be operated from the DCC
power logs in at 1/100 amp. So, if you plan to operate 4 locos simultaneously
with 10 lighted cars and 8 turnouts, then your power needs are:
When sizing a system, I like to allow 50% to 100% for future expansion, so the
above layout would fit nicely into a 5 amp system for HO. In N, it could work
with a 2-1/2 amp system, but S or larger would be into the 10 amp range.
Why not just get the biggest, baddest system to start and be done with it? Good idea, but . . . there is a hitch. Too much power on the track and you run the risk of SERIOUS damage to your rolling stock and track work. Here’s an example: If you have a 10 amp system on your N-scale layout and you derail a wheel on a turnout, the system will be putting about 150 watts into that little wheel and the rail it is bridging. If the system doesn’t shut down, a lot of heat will be generated - think of how hot a 150 watt bulb gets even though much of its energy is going out as light. Concentrate all that heat into a small wheel and the adjacent track and you have melted parts and, perhaps, a welded wheel! However, there is an answer. Break your layout into power districts - three or four are good - and use a power manager (PM42 or OG-CB) to limit the current in any one district to 3 or 4 amps. You have the added benefit of isolation - if one train derails in one section, the others keep running.
Okay, now I know what size system I am looking for.
Selecting the Best Set?
Each
manufacturer has its high points and low points.
I’ve compiled tables to allow you to compare their features side by side.
If you have questions, I’m available by eMail or phone to answer them.
One of the best ways is to run them side by side. However, that is rarely possible.
I do attend shows and bring all sets, so you can do so there. Also, if you are
in the area, you may make arrangements to try them side by side, again, just
eMail or phone to make arrangements.
If you are in a club or have a collection of friends with a specific brand, you
might want to select the same one, as they might be better able to help you get
started. However, just because your friend likes brand X, you may not.