# Broadway Limited F7A - How to change default direction (DC)



## davefr (Oct 22, 2020)

I'm looking to buy a Broadway limited F7A/B set and a second F7A to be run ABA. (common F7 3 locomotive consist). However I will want the second A's default direction to be in reverse so they don't create a tug of war. These units are DC, DCC and come with sound. I plan to start with DC only. Will I be able to easily swap a couple wires in the second A unit so it's default direction is reverse?

I know all this can be done via DCC but I want to start with plain old analog DC.


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## Dennis461 (Jan 5, 2018)

DC only.
No need to change anything on newer equipment.
An "A" unit will go left on your track, pick it up turn it around, put it back on the track, and it still goes left.


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## davefr (Oct 22, 2020)

Dennis,
Thanks, so a DCC motor running off of DC will always start in the same direction regardless of it's orientation on the track? That makes it easy.


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## Aard D'Vaark (Aug 1, 2019)

if you -need- to change anything, just reverse the two wires on the motor .. not real quick but pretty easy ..[ for DC]


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## mesenteria (Oct 29, 2015)

DCC is an AC current that the decoder reads. From there, the decoder rectifies the AC current to DC and that is why the DC can motors run so well.

With DC, if you want to reverse the direction of travel, you MUST reverse the polarity. Either to the rails or to the motor. Simply picking up the loco and turning it back-to-front won't make it run the other way. It will still move in the same direction, but this time backwards to how it was facing previously.

If you are consisting two diesels, and want the trailing one to run in reverse so that the two locomotives move in one direction (two A units back-to-back, for example), you'll have to reverse the wires to the motor in the backing unit. If there were decoders installed in each locomotive, you'd simply switch CV29 (if I recall) to a different bit and it would run in reverse.


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