Digitrax

[adari]

What type of power pack do you need to power the digitrx super chief 8 amp radio equipped model.
thank you

[richG]

http://www.digitrax.com/prd_re_sc_set.php

More info.
http://www.google.com/search?hl=en&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=digitrax+super+chief+8+amp+radio+equipped&spell=1

Rich

[Frisco]

Unles you are using G scale I would recomend the 5 amp instead.

[Jim Banner]

Digitrax specifies 12 to 28 volts dc or 12 to 20 volts (RMS) ac.  For full output from a DCS200, the supply must be rated to supply at least 8 amps.

Most people choose to use a transformer and let the DCS200 convert the power to dc internally.  What the specifications mean, in terms of a transformer, is that it must produce at least 12 volts ac when you are drawing 8 amps from it and must not exceed 20 volts ac when you are drawing no current from it.  (Remember that transformer voltage goes down as current supplied by it goes up.)  Usually a 15 or 16 volt transformer rated at 8 amps or more will work just fine.

I highly recommend that you use a fuse between the transformer or dc power supply and your DCS200.  Then an internal fault in the DCS200 will be limited to 8 amps and not the full short circuit current of the transformer.

The DCS200 can produce enough power for a large scale or 0-scale layout.  But you will need some form of power management to limit the current at the rails to less than 8 amps, if your layout is smaller than 0-scale.  A Digitrax PM42, for example, will allow you to divide your layout into four sections, called "power subdistricts," each of which can be adjusted for a maximum of 3.5 amps (N-scale) or 5 amps (H0-scale.)  With such a power manager, a short circuit can shut down one subdistrict without affecting operation in the other subdistricts.  A power manager can also limit the current at any point on the layout to a safe level that will not damage your trains while still providing lots of power to run many trains.

If your layout is of a size that could be run on 5 amps, choosing an 8 amp booster is still a good idea.  The extra capacity  (60% more available current) means your booster is loping along rather than straining at full output.  It also means you have room for expansion.

You will also need a small 12 to 15 volt transformer ("wall wart") to power your radio/IR receiver but I believe that comes with the set.  Do NOT attempt to power the receiver by connecting it to the transformer or supply powering the DCS200.  Your walk around throttle will need a 9 volt rectangular battery to use it in the wireless mode.

[adari]

Do you need the UR91?

[Jim Banner]

You only need the UR91 if you want to operate your trains using the DT400R wireless capabilities.  The UR91 is the receiver which can work with both radio and Infra Red throttles. 

An alternate receiver, the UR90, also allows wireless operation but with Infra Red only.  The DT400R throttle can operate both radio and IR receivers, or both at once.  The DT400 throttle can operate only IR in the wireless mode.  Both throttles can also operate in tethered (wired) mode.

Indoors, radio wireless has a slight advantage over IR wireless - it goes through walls and around corners.  But radio wireless is more expensive than IR wireless, even if you have to use multiple receivers to cover all the IR dead spots.  And the extra cost applies to each additional throttle as well.

Outdoors, there is no choice.  That big IR emitter up in the sky wipes out the throttles' puny IR outputs, making radio wireless the only practical solution.