# Recommended voltages for locomotives



## Spruslayer (Dec 13, 2020)

Howdy to every one on this fine frigid Christmas nite.
Once again in my newby way i have been looking at locomotives to run on my Kato unitrack N layout
I have a BLI SD40-2 and i have successfully set up an oval of track and ran the train pulling one boxcar.
However ,after reading the online owner manual it states the loco will start the light and sounds at about 7 volts and will be at full power at 16 volts.
The standard sx power pac that came with the Kato M2 measured only 13.3 on my volt meter with the throttle wide open.
I'm not concerned about that other than the train may not go as fast as it can. That got me wondering about other brand of locos so i went to the Kato website to read about their offerings' discovered that Kato recommends 12 volts as the maximum operating voltage which means i wouldn't want to run their locos on their track with their power pac on full power?Bachman info that i could find talked about not letting the track voltage exceed 21 volts due to the sound decoder in the loco.
My question is will ti damage a loco to run it at a higher voltage the recomended.


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## DonR (Oct 18, 2012)

N and HO scale model locos run on a 0 to 12 or so volts DC. Some power packs may
put out a few more volts or a few less...it really is not a concern. You simply raise
the control to a loco speed you find comfortable. The specifications you have read are
there to warn against using an unapproved power source. Any such specified for
N or HO trains will be safe to use. 

With a DCC control system the track carries a constant approx. 14 Volt modified AC.
Each loco has an onboard decoder that rectifies the AC to DC and feeds the motor
according to digital instructions sent by the DCC controller. 

Don


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## wvgca (Jan 21, 2013)

running your loco at full power from the transformer is usually not recommended .. the loco doesn't look realistic, and the chance of it coming off the track and crashing is quite a bit higher, lol


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## mesenteria (Oct 29, 2015)

Spruslayer said:


> Howdy to every one on this fine frigid Christmas nite.
> Once again in my newby way i have been looking at locomotives to run on my Kato unitrack N layout
> I have a BLI SD40-2 and i have successfully set up an oval of track and ran the train pulling one boxcar.
> However ,after reading the online owner manual it states the loco will start the light and sounds at about 7 volts and will be at full power at 16 volts.
> ...


Probably not, but if you're talking running an N scale decoder on O Gauge setting for voltage on your DCC-powered rails, it might be expensive in the end.

I mistakenly flipped my scale toggle on my Digitrax system once, but didn't notice until at least a week had passed. I had run one or two HO locomotives that week, and none of them seems to have been damaged. So, if you're in N scale, and run it on HO settings for track voltage, I don't foresee much of a problem. After all, the damage comes in the way of heat, and heat is a product of the amperage the motor draws. The motor draws amperage based on the throttle setting assigned by the decoder, and the decoder gets its marching orders from......you. If you, like I do, never run your locos as full speed, you're not likely to draw much amperage. If you run them with a lot of trailing cars, and up grades, you may be demanding your drive system inside the locomotive to draw well over one amp, maybe even two if it's also producing sound at any volume. Hot electronics and motors don't last long.

What I'm saying is, even if you're set for HO scale in voltage, with DCC you tell the decoder how to acquire and to meter out power to its hosted components. If you keep train speeds, and the loads they drag around, to a modest value, you'll never have to worry much about excess voltage.


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## Spruslayer (Dec 13, 2020)

Thank you all for the help. The BLI SD40 a runs at a scale speed Fairley fast But watching from my prototype eyes it appears not to be moving fast enough to through it of the rails at top speed. In my foggy memories as a 10 year old which was the last time i had a train i could run it too fast and throw it off the track. I think it was a Tyco HO scale. Today i have the bench work far enough along that i can lay track by the plan i did in SCARM so far it has worked perfect even negotiates threw two turnouts to a double curve.So for now my voltage worries are gone.After the layout is complete i will start to wire it For DCC to use with a NCE Power Cab.
🚂🚂🚂


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## Shdwdrgn (Dec 23, 2014)

DonR said:


> N and HO scale model locos run on a 0 to 12 or so volts DC.


HO scale loco motors can be anywhere from 12 to 18 volts, so it pays to pay attention to what you have. My DCC power pack puts out 16.4V which works fine with the various Digitrax and Soundtraxx decoders I use. I've even run 12V motors on this setup without an issue (of course I don't run them at full speed except for a short period to test them).


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