using auto battery chargers for track power

[piercedan]

"Beauty and I are new to model railroading.  We are interested in garden railways and have a Bachman Pennsylvanian.   How about using a solar battery charger, two 12 volt wet cell batteries, and a control circuit consisting of an on/off switch, potentiometer, DPDT switch, and possibly volt/amp meters?  Has anyone tried this? "

 

A potentiomenter is difficult to use as it needs to dissiapate lots of power.  If you have a 18 volt power source and a train that uses 2 amps at 12 volts, the rheostat must be able to handle 6 volts times 2 amps or 12 watts.  Resistor wattage needs to be double the load so you need at least 25 watts.  Notice that when going to high power potentiometers, the alternate name I used is rheostat.

Now go to 24 volts at 2 amps and it is 50 watts.  These rheostats cost a lot of $$$ and are big.  I remember using these for my HO trains.

 

In large scale, manufacturers use solid state electronics as transistors hich are much smaller and the voltage output remains more constant when the load changes such as running through curves and grades.  Many controllers use very efficient/low resistance mos fets and even can keep the heat down.  Power loss with these is so low, no fans are needed.

[Mt Beenak]

Griffdog,

I do not know the article, and am only writing from my own experience. I have always used a battery charger with a 10 amp rating to power my entire layout, inside and out. It puts out 13.8 volts, and that is plenty to run a Bachmann Shay, Climax, a couple of LGB 040's and assorted others, lights inside and tortoise switch motors. I like the fact that none of my locos 'race' at the maximum output of 13.8 volts.

I use old fashioned wire wound rheostats as speed control, and have a thermal cutout with auto reset for protection. So it is old fashioned and there is no DCC. It Works!

The only drawback is some of the recent releases, particularly the Galloping Goose units run very, very slow on 13.8. volts, and seem to need 18 volts to run properly. This was a visitors train, so no problem for me!

I advise against using batteries, such as a car battery for controlling through the track, as too many amps are available and you could do damage, up to and including weld a loco to the track in a bad short.

Mick
Mt Beenak, Down Under

[Anonymous]

Go here

http://www.trains.com/trccs/forums/1277853/ShowPost.aspx

Toad

[beauty and the beast]

Greetings from Beast!

Beauty and I are new to model railroading.  We are interested in garden railways and have a Bachman Pennsylvanian.   How about using a solar battery charger, two 12 volt wet cell batteries, and a control circuit consisting of an on/off switch, potentiometer, DPDT switch, and possibly volt/amp meters?  Has anyone tried this?  

 

Happy railroading

 Beast 

 

[markperr]

I see no reason why you couldn't use a battery charger to power the rails.  That said, you would still need some sort of throttle control to adjust voltage.

Mark

 

 

[Anonymous]

Dog,

Yes it was in GR mag. about two guys (or three) that made a GRR with track power of three Walmart ($19.95) battery chargers. Was a large lay out if I remember and I think was in the center of GR mag where the staples show though or center of mag.

I remember it brought alot of heated debate.

Toad in Da Swamp

Update: I remember it was around a very large oak tree and I think is when I left this board about 4 yrs ago? But it was 2 men and it just gave info. that they used the auto chargers. So you would be looking I would think for the name of the RR or showcasing the RR. I remember cause at that time I only got GR mag, Trains & Classic Trains in my hands to read so it was not the others.

William

[piercedan]

It was on another forum and there could be a voltage issue if you tie 2 in series.

 

Also, the output side could be tied to chassis ground and then you would have to float one charger which is dangerous and can cause a shock.

 

Best bet is to get a regulated supply with no more than 24 volts output, and at least 20 volts minimum.  Current rating wouild depend on what you are running. I allow .5 to 1 amp per motor depending on the manufacturer. 

 

In order to charge a car battery, you need 14 to 15 volts.  This would place 30 volts to the trains and many engines/lights/electronics are rated for no more than 24 volts and some DCC unitsa are rated 18 volts max.

 

You could use a 12 volt and a 6 volt unit in series to get approx. 22 volts and that would work.

 

 

[Rene Schweitzer]

Griffdog,

I don't think this was in our magazine. I searched our indexes and even emailed Marc Horovitz, but to no avail. Sorry.

[cabbage]

Sorry, but I don't recall this.... What I have seen and heard of, is using ex PC-AT power supplies to provide the track power through a switch mode convertor.

regards

ralph

[Anonymous]

  I know  that i have read an article in Garden Railways about someone who used auto battery chargers for his power.  I have not been able to find this article again.  Does anybody remember this article?????

Thanks,

griffdog