Volts and DCC

[wally]

Does a Bachmann Spectrum 2-8-0 use more voltage with the decoder installed for forward motion, then without the decoder installed?Thanks Wally

[richg]

The loco uses whatever voltage you send to it with the controller.

Rich

[Jim Banner]

Under what circumstances?  What decoder?  Installed by whom?  Voltage measured where? 

No matter what system you are using, you will need the same amount of voltage applied to the motor to make the train go the same speed with the same load behind it.  When you use DCC to operate a locomotive with a decoder installed, the voltage on the track stays constant but the voltage fed to the motor varies as you speed it  up or slow it down.  This is true when the decoder is set for forward motion and is also true when it is set for reverse motion.

If you are talking about running the train using dc on the track, then it may take more dc voltage measured at the track to run a locomotive at a particular speed when it has a decoder installed than it would take to run the same locomotive at the same speed without the decoder installed.  This again assumes the same load behind the locomotive.  You cannot install a decoder for just forward motion or for just reverse motion.  So if it takes a higher dc voltage on the track to run a decoder equipped locomotive in the forward direction, it will also take a higher dc voltage on the track to run that same decoder equipped locomotive in the reverse direction.  I believe this applies to all Bachmann 2-8-0's that were sold with DCC on board, both Spectrum and Standard, with both motion only decoders and with motion plus sound decoders.  There are decoders where no extra dc voltage is required on the track if the decoder is present or not present, so if someone had installed one of these into a Bachmann Spectrum 2-8-0 after purchase, that 2-8-0 would not require more dc voltage on the track after installation of the decoder than before the installation.

Sorry about the long, complicated answer but without the specific circumstances in the question, I tried to cover all the circumstances in the answer.

Jim 

[Doneldon]

All other factors being equal (probably impossible to accomplish) a decoder-equipped loco will require marginally more power than a non-decoder loco due to the "overhead" of the decoder itself.  As a practical matter, the difference should be so small as to be nearly inconsequential.

          --D

[wally]

Thanks for the help. Wally