# dcc on FA/ B units



## domer94 (May 4, 2015)

this may be a dumb question , but when running an aristo FA/B together, do both have to have a separate decoder? or can the B unit piggyback off the A.

thanks


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## Treeman (Jan 6, 2008)

It is possible to run both units from one decoder, if it has enough current capability. It is however generally recommended to install a decoder in each.


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## Dan Pierce (Jan 2, 2008)

Look at the specs of the decoder and remember the max current is for motor, lights, and smoke units added together. Use leds for the lights (place dual lights in series like the ones on the FA fake motor) and use track power for the smoke to lesson the current draw of these items.


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## Treeman (Jan 6, 2008)

Dan, What are you using to turn smoke on and off direct from track?


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## Greg Elmassian (Jan 3, 2008)

Zimo and QSI and others have high current outputs for operation of smoke. They can be controlled like other function outputs.

Greg


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## Treeman (Jan 6, 2008)

I have 3 USA diesels to do,I planed 8A NCE decoders, they have 1/2 amp outputs. The locos already have Phoenix.


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## Greg Elmassian (Jan 3, 2008)

If you want to use those decoders to run smoke units over 1/2 amp add a relay. 

Also, although all 8 outputs are rated at 1/2 amp each, it might not be able to run all at the same time at max current.

Did you look into the D408 decoder? They have lower motor current, but they have 2 outputs that can handle 1 amp each. They are cheaper, so maybe one per loco if you have smoke units that want to run 1 amp.

Greg


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## Dan Pierce (Jan 2, 2008)

Zimo does have a non sound decoder which has the heater and smoke motor controls with a 6 amp total current rating.


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## Treeman (Jan 6, 2008)

Greg, I do have some relays with a 12VDC coil, that I considered. Was afraid of the 4A NCE because if the high motor current, did not realize that the other outputs had a higher rating.

Dan, is that 6A is total? What is each output rated?


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## Greg Elmassian (Jan 3, 2008)

It is relatively new, if you go to the NCE website, they indicate the D408 manual needs updating, and it identifies the two 1 amp function outputs.

You would want one decoder per loco, but that makes more sense, they are cheap, and then you can consist the locos properly or run them independently.

Greg


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## Treeman (Jan 6, 2008)

Yes, I always install a decoder in each loco.


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## Greg Elmassian (Jan 3, 2008)

I like the way you think Mike 

Greg


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## Dan Pierce (Jan 2, 2008)

The Zimo 6 amp rating is total current, but will handle a 10 amp surge.
Also note Zimo specs voltage at 30 volts but 50 volt surge on many decoders.


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