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Unread 25-02-2012, 16:57
Cal578 Cal578 is offline
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AKA: Gerry
FRC #0578 (Red Raider Robotics)
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Re: Jaguars vs Victors

Quote:
Originally Posted by Joe Johnson View Post
...you will have two current paths -- and since loses are an I^2 R problem, halving your current can effectively quarter your electrical heat dissipation.
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.
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R3: Red Raider Robotics (FRC Team 578)
Fairport, NY, USA
www.FairportRobotics.org
2016 Finger Lakes Regional: Semifinalist on Alliance 7 (1128, 2010, 578)
2016 NYC Regional: Finalist on Alliance 3 (3419, 578, 3017), 4th seed team, Team Spirit Award
2015 Finger Lakes Regional: 8-3-0 in qualification, 7th seed, Quarterfinalist
2014 NY Tech Valley Regional: 8-4-0 in qualification, 13th seed, Semifinalist
2013 Finger Lakes Regional: 4-5-0 in qualification, 26th seed, Alliance 6, 1-2 in tournament
2012 Buckeye Regional: Gracious Professionalism Award, 7-3-0, 14th seed
2011 Finger Lakes Regional: Engineering Inspiration Award