Large Scale Central

OK, battery gurus, help out this electrically challenged railroa

Electronics Power and Sound
#1

I understand that speed of the loco is controlled by the voltage applied, and that runtime is controlled by amps. At least, I think that is what I understand. At least, I accept it as axiomatic.

Now, let us assume an SD-45 from Aristo, with, say, 5 boxcars and a caboose. On the same level track, at the same average speed, which battery pack is going to give the longest run time, a 14.4V, 3200mAh or a 16.8V, 3200mAh battery pack?

Will the extra subC cells give a longer runtime, or is it only the mAh that controls runtime? One would think that with two extra “tanks” of fuel, one could get a longer runtime.

#2

I’m not the battery guru, but since the motors have the same amperage draw the run-time should be the same since the batteries have the same mAh rating.

#3

So, having an extra “Tank of fuel” means nothing?

#4

Steve,
I am exactly no expert on this.
But having said that,
On most of my battery cars I have 2 each 14.4v or 2 each 12v and they are hooked up parallel with a diode at each battery keep the batteries from constantly equalizing. And you saw at our last run, I ran a two motored LGB SV mallet pretty much all day long and she was still going strong at quitting time.

Run times are limited by:
Amperage
Weight or length of train
and grades.

My 12 bricks are only 2100 Mah each, and my 12 sticks are 3000 Mah.
Bricks are square is shape for box cars, etc.
And sticks are long and slender for under loco long hoods.

Remember, I haven’t a clue. I do what works for me.

j

#5

motors run on power… so runtime is a factor of amps and volts…

you would do well to rate “runtime” in relation to watt-hours used…

(assuming you can achieve the speed you want)

Regards, Greg

#6

Steve,
Use only the voltage necessary to achieve a realistic top speed when flat out.
A loco will NOT run any longer because of higher voltage.
If you have a higher voltage than is necessary the controller/loco has to burn off that excess volatge in the form of heat.
In other words the energy is wasted.

#7

Steve,

The big Aristo diesels will use higher voltages to acheive higher speeds. If you like to run fast go for the bigger packs. I usually run my E-8 with smoothside passenger cars off of track power (about 18v) at top speed. The top speed for the Aristo 3 axle diesels is around 60 smph (a bit slow for actual passenger service). For a freight consist you may not want to run at top speed. I also have a battery car for it - a 40 foot headend boxcar that has an Aristo trackside TE in it (not as nice as my RCS but I picked it up unused second hand for $50). I use 16.8 v 3.8 Ah subC NiMH packs in it. They put out 19 v at full charge and I get 3 hours run times from them with just lights (no smoke). That’s with a boxcar and 3 smoothsides on my layout with some grades. I have also tried my 14.4 v packs in this and it runs fine just with a slower top speed.

-Brian