wrote in message
...
On Mon, 6 Apr 2015 17:31:57 -0400, "Jim Wilkins"
wrote:

"Ignoramus32423" wrote in
message ...
On 2015-04-06, Larry Jaques
wrote:
On Mon, 06 Apr 2015 10:26:40 -0500, Ignoramus32423
wrote:

On 2015-04-06, Lloyd E. Sponenburgh lloydspinsidemindspring.com
wrote:
Ignoramus32423 fired this
volley in
:

The good news is that, as they run, even after a while, the
heatsink
is only barely warm.

What you did not say was 1) the raw battery voltage,

12v nominal

2) the current (both peak and average) for the arm

Not sure, not a lot. The arm operates very intermittently.

3) the current(ibid) for the tracks.

Not sure what is the current for the 5v tracks, but my best guess
is 1.2
amps when driving in a straight line, and about 3A when turning
on
a
dime.

Are you using spring-loaded momentary toggles on that controller?
Seems less than optimal.

Any suggestions?

To check current draw, throw one of these inline with the power
line,
using standard USB connectors. They're great little units, and
you
can't beat the price.

http://tinyurl.com/oyq53ro
I picked up a couple when they were a buck, with free shipping.
One went to my niece, with a power module for her cellphone.


This is cool, indeed!

i

The problem with them is the low maximum voltage rating of 7V. I
have
a similar AboveTEK meter.

This has a more useful 33V rating and resolves to 0.1mA below 1A,
1mA
above.
http://www.amazon.com/DROK-Digital-D...30828&sr=1-152

It also shows total power like a KillAWatt for DC. I haven't tried
the
simpler, less expensive versions.

-jsw

The cheap ones are far from accurate. I bought 2 on ebay - both were
in-accurate, and they didn't even match each other. (readings were
different and didn't match my 3 multitesters, that all agreed within
less than 1/10 volt and less than 1/100 amp

Look closely, mine had tiny calibration trim pots.