Large Scale Central

A little cornfused

Electronics Power and Sound
#1

OK.
It has been drummed into my head by Dave and others.
USE BIGGER WIRES when installing sound systems, decoders, etc.
Then why does LGB, Bachmann, USA, etal use small wires??? 20-22 gauge.
Then we hook up 10-15 Amp LGB, Bridgewerks, Crest. etal and go merrily on our way down the track.

Why can’t we plug our RC/Batts directly into the plug on the back of a Bachmann, LGB, etal with those 20-22 (whatever) Gauge plugs hanging out of them. Instead of taking the lokie apart and wiring 16-18 gauge directly to the motor, that most Bat/RC installers do?

Aren’t Batteries less power than 10-15 Amp Bridgwerks, LGB, etal power supplies?

My battery pack from Dave will be around 2 Amps. I’ll never use 2 amps with the loco and a few cars.

Why do we have to use that big wire?
Why can’t we plug our bat/rc stuff from the tenders straight into the loco? (After we remove the brushes, of course).

Someone please explain to my why Batteries/RC at 2 Amps is “hotter” than the same engine on the track power with the aforementioned power supplies.

I know I am old and senile, but I need a clear explanation.

Thanks,

TOG

#2

John -

It has to do with voltage drop and power lost as heat. When you are using a 15A track power supply and the Loco only needs 2-3 A you don’t much care how much of that power is wasted trying to force itself down the small wire. BUT - When you are drawing that power from a battery you do care about waste because wasted power shortens run time.

The experts may now correct my oversimplification :smiley:

Jon

#3

OK, Maybe it’s a little clearer now.
But will it hurt to plug your battery tender, or trailing car directly into the factory plug?
I know Aristo now makes a plug for this and it isn’t heavy wire.

jb

#4

No. It will work. I’m using the Aristo plugs and stock wiring on a triple headed RS-3 powered by a trail car. My battery is a big honking Ryobi 1+ drill battery so I get reasonable run times despite the lousy wiring. Worst case the loco stalls on a grade when your not watching and melts the little wires trying to pull more amps out of the battery.

Jno

#5

jb,

I lost my SD-45 inside Jens’ tunnel once using the stock wires. I had to climb down the man-hole. Do you have any idea of what kind of critters lurk there?

#6

John,
The plugs hanging out of various AristoCraft locos will handle the power requirements for one loco without any problems when used to carry the battery source.
Two of the bigger locos is starting to stretch the friendship.
Three locos is a definite No No.

The kits that I supply for converting any loco to an AC standard are made with 20 gauge wire, which is a thicker gauge wire than whatever AC is using.

#7

Thank you, Tony!
jb

#8

Just like with water, the bigger the pipe, the less the resistance.

#9

Steve Featherkile said:
jb, I lost my SD-45 inside Jens’ tunnel once using the stock wires. I had to climb down the man-hole. Do you have any idea of what kind of critters lurk there?

:lol: :lol: Steve, Was that before or after you got into that hole?

(http://www.clicksmilies.com/s0105/teufel/devil-smiley-023.gif)

#10
Steve Featherkile said:
jb,

I lost my SD-45 inside Jens’ tunnel once using the stock wires. I had to climb down the man-hole. Do you have any idea of what kind of critters lurk there?


I spent many a relaxing hour in that hole 15 years ago filming trains running along the edge.

#11

Depending on which wire gage chart you look at, you will see that 22 AWG wire will easily handle 7 amps (20 ga. = 11 amps). Your motor’s stall current is likely less than that. As far as voltage drop goes; 22 ga. over 2 feet of wire running 5 amps is about 0.16 volts, 20 ga. is about 0.10 volts. I would use 20 ga., if it is convenient, but 22 is fine. The problem with larger gage wire between the loco and tender is usually not much flexibility.

#12
John Bouck said:
Steve Featherkile said:
jb,

I lost my SD-45 inside Jens’ tunnel once using the stock wires. I had to climb down the man-hole. Do you have any idea of what kind of critters lurk there?


I spent many a relaxing hour in that hole 15 years ago filming trains running along the edge.

jb-

That was 15 years ago! There have been some strange critters take up housekeeping since.

#13

None stranger than John! 15 years ago I was just a small child! I was told to stay out of holes with weird critters in them.

#14

That’s because we didn’t think it appropriate for you to be down in the hole together with an old geezer like John…:stuck_out_tongue:

:smiley: