Testing locomotives with a battery

[6axlepwr]

I know it is OK to test HO scale locomotives with a 9v battery. Is it OK also to test N-Scale with the same 9v battery?

I do not have a transformer and I do not have decoders yet to put in the models. Just want to make sure they run properly after I reassemble them from clean up and custom painting.

Thanks.

Brian

[davefoxx]

I know it is OK to test HO scale locomotives with a 9v battery. Is it OK also to test N-Scale with the same 9v battery?

I do not have a transformer and I do not have decoders yet to put in the models. Just want to make sure they run properly after I reassemble them from clean up and custom painting.

Thanks.

Brian

Not the same battery.  You'll give the N scale locomotive HO scale cooties. 

Seriously, you should have no problem, because most N scale locomotives can safely handle up to 12 volts (at least that's what the N scale setting on my Digitrax booster is supposed to be putting out as a maximum safe voltage).

Hope this helps,
DFF

[TiVoPrince]

Realistically
most hobby shops have used 'train set' transformers that can truly test over a range of voltage for pennies over the cost of a few 9volt batteries.  Throttle circuits have been published here that use repurposed wall transformers and a couple of components that would make fine bench throttles and give a more realistic demonstration of overall performance...

[Scottl]

9V batteries sit on n-scale track nicely.  No issues at all.

[fredmoehrle]

And you can test the battery by licking the posts.
A new one hurts a little bit.

[djconway]

Always bring a new 9v battery to the RR shows and swap meets.  Has saved me $$$ more than once.  Runs like a what?

[mmyers]

Always bring a new 9v battery to the RR shows and swap meets.  Has saved me $$$ more than once.  Runs like a what?

Just don't drop it into a pocket full of keys or coins. Unless it's winter...

[peteski]

A 9V battery is perfect for testing N scale locos!  No wires needed as the terminals are spaced just right to contact either the wheels or a piece of track.  It is also a good way to test DCC models as most decoders have the analog mode operation enabled by default.

[woodchip]

The other benefit of testing with a 9 volt battery is some decoder equipped engines will run erratically if there powered buy a DC throttle with a pulse feature. the battery is straight DC and a DCC equipped engine will run as smooth as running it on DCC. The only problem would be if the decoder is set to not run on DC but that's a whole other issue.

             Cheers from Canada
                         

[rogergperkins]

I found a video on YouTube where the person ran an n-scale locomotive with a 9 volt battery.
He was demonstrating DC to DCC.

[nkalanaga]

fredmoehrle: I've done that a lot of times in the past, but don't have anything that uses 9 volt batteries now except the smoke alarm.  That used to be a common way to test low voltage circuits before meters were readily affordable.

[DKS]

There are a number of small throttles that use a 9-volt battery as a supply. They're mostly marketed to Z scalers, where the motors are smaller and will run longer on a 9V, but they can be used for small N scale layouts as well.

[Kisatchie]

Hmm... I remember when
Kiz tested a loco with a
car battery. I was picking
shrapnel out of his fat
head for a week...

[fredmoehrle]

Hmm... I remember when
Kiz tested a loco with a
car battery. I was picking
shrapnel out of his fat
head for a week...

THREAD DRIFT ALERT:
There's a story around the Ann Arbor area of a fellow with a large layout that developed a short suddenly.
After having his crew of about 8 people search the layout, they pulled all the rolling stock of the layout, disconnected the power source, and touched the rails with jumper cables attached to a truck battery.
Sure enough, a turnout began to smoke!
Replaced that and, no more short.

[nkalanaga]

Model railroads used to be commonly run from car batteries, before DC rectifiers became cheap enough for everyone to afford a power pack.  12 volt trains will run off any 12 volt supply as long as it can supply enough current, and the battery won't overload anything just by being connected to the track.

As fredmoehrle noted, short circuit protection was essential, just as it is today if you have one of the high amperage DCC systems.  A common current limiter was an auto head or tail light bulb, depending on how much current you needed.  Until you near the operating current, bulbs have very low resistance, but once they turn on, that's all the current they'll pass.  I have the same system on my accessories and lights, using multiple 1 amp dome lights.  That way everything can run off the cheap 25-amp power supply without risking a catastrophic short.  no one circuit can draw more than 1 amp, even if it shorts out.  It also makes overloads very easy to find...