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Unread 25-02-2012, 17:07
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Re: Jaguars vs Victors

Quote:
Originally Posted by Cal578 View Post
Formula is correct, application is almost correct.
The total current didn't get halved, it just got split into two paths. So, if everything else is the same, the power dissipated per path is a quarter of the original, but you have twice as many paths, so the total power dissipated (lost) is half the original (which is still a good thing).

To put it another way, putting another identical load in parallel with the first means your R is cut in half, which directly says that the power is cut in half.

Also, I just said "if everything else is the same", but if you're changing motors and/or gearing, then everything isn't the same. If new motors or gearing gives you a better match of motor to load, then that will be where you see the biggest improvement, and heat caused by losses becomes a smaller issue.
You are right, I was sloppy. But here is the thing. It is heat that ultimately kills the electronics. If you halve the current per leg, then that leg is going to see much less than half (~1/4 to first order) of the heat it would have otherwise seen.

So from a stress your electronics pov, it is a better than halving. That was my point, which I think is still valid.

Joe J.
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