Subject: Re: Reducing contact resistance for low volt use?
Summary: What do you think of these ping times eh?
Reply-To: You can't see me, and I pass right through planets...
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Date: Tue, 07 Jan 2003 09:17:47 GMT
NNTP-Posting-Date: Tue, 07 Jan 2003 04:17:47 EST
On Tue, 07 Jan 2003 01:41:56 GMT, jmuchow@SPAMMENOTcamlight.com (John
Muchow) Gave us:
>>>>>I didn't realize that the plating lowered the resistance that much for
>>>> Ohms per foot is ohms per foot. Silver is a better conductor than
>>>>copper. AC or DC. If you are trying to garner every little bit, how
>>>>could it be negligible?
>IMHO, the gains would be negligible if I had to pay significantly more
>money for a tiny fraction of a percent of reduced resistance.
38 cents a foot. A buck or two a foot... whoopie doo.
You just said that you fry motors and batteries all the time, let
alone "embattled bot" damage. This expense would seem muy poquito, by
comparison. Do a google search, if you didn't catch that one. :-]
Even at five dollars a foot (which it is not), you could show a
better connected system as the contacts would also be better. THAT
resistance IS important. I would bet a unit would run better with a
good set of silver plated feed lines over copper. Hell, find pure
silver, and gang up a cable yourself. WOW. All I know is that my
jumper cables worked better than my dad's, and it was due to gauge and
clamp attachment method.
It would also gain a bit of "prestige" as it were.
It would be like showing off your $200 video cable on your home
theater to someone, when theirs operates just as good from a ten
dollar cordset. It's all about image.
You could brag about having huge, silver plated feed lines, and the
next thing you know, they are all following suit. :-]
The resistive difference seems to be around 2% or a touch more.
Down at fully clamped voltage levels, I'd say that is significant.
My car started, using my jumpers, and dad's didn't different gauge
and poor connections. Silver is better at both connections, and
conductivity. For me, a no brainer. The price difference would be a
negligible impact, unless you constantly budget in for battery
failures, and motor thrashings. If she don't stall, she hauls balls.
If these batteries are so capable, would the delivery method be
important as well?
What was it we were talking about again? Tee hee hee.
Delivery problem to motor solved. If stalling continues, battery
capacity *must* be increased. That *is* the entire circuit.
Batteries, terminations, traverse line, terminations, motor winding.
Silver could only help. Guaranteed to be non-detrimental.
Among metal conductors, it is the best. The only other room
temperature compound that beats it is it's own product, silver
oxide... in pure form. Make some silver oxide bars.
By the way, if you do use any solid wire or bars, make sure to form
all bends very very slowly as such materials as copper "work harden",
then micro-fracture, causing weak spots in the wire or bar. If one
takes a bare wire of a big enough size to see well, and bends it
sharply, and fast, it will exhibit heat at the bend point, and its
lattice will fracture there, then harden. Returning a bend back
straight, further damages the wire structure. This is why a wire kink
during a winding operation or for making voltage rails cannot be
merely uncurled, and consider the wire viable. For bars, there is a
minimum bend radius, and bends should be performed very slowly, and
with a single motion to the stop point of the bend. Ideally formed to
its final point on the first shot. This is why failures at high
currents in large plating tanks and such nearly always occur at an
undulation or bend in a voltage rail bar. The are poorly conducting
"hot spots" in such points. Both due to shape (in high flows) and
structure micro-fracturing during the forming process. A fuse with
kinks in the fuse band area will blow at one of the kinks.
I do not know if silver has a "work hardening" type property to the
same degree as copper, but copper is quite dramatic.
Isn't there a relay (solid state perhaps) involved here as well?
Voltage drop? Contact count? Mercury switches?