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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...
References: <email@example.com> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org>
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Date: Tue, 07 Jan 2003 05:44:56 GMT
NNTP-Posting-Date: Tue, 07 Jan 2003 00:44:56 EST
On Tue, 07 Jan 2003 02:34:34 GMT, jmuchow@SPAMMENOTcamlight.com (John
Muchow) Gave us:
>This is COMBAT robotics and things get destroyed...all the time. I
>run my 12V drive motors at 24V and they work fine. Do they get hot,
>of course! But I know that and it isn't a problem for a 3 minute
Sure it is. If they get too hot, they stall because you have reached
the currie point of the perm magnets in them. That is probably one of
the main problems, when you overvoltage the motors. Actually the
currie point poses a problem for steel and iron parts as well.
Their makers could tell you about it, I'm sure. I don't think the
windings like it a lot either. Having done it so much, I'm sure you
already know this.
If they are electrically excited fields, you are using juice on the
batteries in two places, not just one. I was thinking they are perm
mag motors. Still heat can pose serious problems inside those
> I draw approximately 40-amps from each 24V string of 3000mAH
>cells (one per motor) and that's no where near "spec" for the
>batteries or the motors.
It doesn't remain at 24 volts either, does it?
> And my bot isn't pushing the performance of
>its components nearly as much as many others are.
I'm just saying that the job could probably get done without
stressing them at all.
>Even the R/C car and airplane builders use their cells at very high
>discharge current levels
I know. I make controller circuits for them. I stay inside the
Since you extend outside it, and work at low voltage levels, have
you sought lower voltage motors that put out what your overvolted
motors do? Those extra bits of efficiency are what you seek anyway.
One step at a time.
Just like the old days of drag racing with stock vehicles. It goes
from parsing out pieces of the car to reduce weight to porting out the
heads to increase flow. One step at a time.
I merely suggested that power is power, and you should be able to
find a motor that delivers your needs within the range it was designed
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