# Transformer wattage



## artp51 (Oct 31, 2011)

I am building a new layout that will contain 97 feet of 0-27 track. Loco and 6 cars only. What kind if wattage will it require? How far apart should drops be?


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## crazdgunman (Oct 21, 2011)

my layout will use 50' of track. It is a wall hanger around the rec room. I too would like to know about transformer power and drop outs. I'm sure some experienced folks will enlighten us soon.


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## Dave Sams (Nov 24, 2010)

Here I go....

I have about 175' of track. But the amount of track doesn't matter as much as what you are doing.

I run all post war trains without any fancy controls. I have about 200 lights and lots of accessories. 

I can run 6 "things" at once and use 3 90 watt 1033's and 3 45 watt transformers. The smaller transformers are for things like a dedicated line for my trolley or gang car, a circle for hand cars and such.

I don't run multiple locos on one track and my trains are limited to 8 cars.

For all my accessories, I use 3a 12 volt transformer.



Only one loco and 6 cars.......for now!


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## Reckers (Oct 11, 2009)

Okies....I'm gonna give you guys one of those irritating non-answers and others will chime in to flesh it out. As Dave Sams pointed out, "what you are doing" is one of the criteria. Your circuit consists of a transformer, your lead wires from the tranny to the track, and your locomotive. If you had perfect conductivity, a measly 50-watt tranny would be plenty because the only place where the circuit is complete is the spot where your locomotive is sitting...you could have 12 miles of track and the circuit is still right there.
Now, in real life, you have some resistance in the rails, but more where they join together, more on the surfaces of the rails and wheels if they're dirty, all of which come into play. Tight connections, clean wheels and rails make your operation efficient.

Others will surely offer better opinions, but mine is that 100 watts
is plenty for either layout if you're clean. As for drops, I'd quarter the distance and see if that works; if not, add additional drops where needed. For one loco and six, though, you don't need a lot of power, IMHO.

Best wishes,


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## gunrunnerjohn (Nov 10, 2010)

Actually, I think that 100 amps is overkill! 

I'd be considering around 100 watts, which is more like 5 amps for a single train.  Consider what accessories might be powered from the same transformer, each light bulb takes 2-3 watts, for instance.

For long runs of track, there are two different things you can do to insure a good circuit from the power to the train.


Solder each track section to the next with a small jumper wire.
Run a power bus under or beside the track of #12 or #14 wire, and take a drop to the track every 6-8 feet.


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## artp51 (Oct 31, 2011)

*Transformer size*

Thanks for the advice. As you can tell I am rather new at 0-27. I have seen a Lionel TW 175 for sale on ebay. Would that be large enough? Also, my understanding is the center rail and either the outside or inside rail is wired?
All advice would be greatly appreciated. 
Thanks Art


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## tjcruiser (Jan 10, 2010)

Yes, the "hot" power on the AC transformer is run to the center rail, and the return power lead is taken from either of the outer rails.

100 watt should be plenty, per comments above. 175 is more than sufficient, but if you've found a good deal, that gives you reserve for layout expansion, multiple trains (via blocked sections), etc.

TJ


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## gunrunnerjohn (Nov 10, 2010)

I just bought a 190 Watt Lionel KW for $32 on eBay, all it needed was one throttle roller and a new cap for one knob. Works great, all tuned up and ready to power things. If you're patient, good deals will come along on eBay, but you have to be patient.


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## artp51 (Oct 31, 2011)

Thanks for the advice. I will give a shot and see what happens.


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## Reckers (Oct 11, 2009)

gunrunnerjohn said:


> Actually, I think that 100 amps is overkill!
> 
> I'd be considering around 100 watts, which is more like 5 amps for a single train.  Consider what accessories might be powered from the same transformer, each light bulb takes 2-3 watts, for instance.
> 
> ...


He's definitely right---100 watts, not amps! Thanks for the correction, and I'll go back and change it.


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