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Unread 29-10-2015, 13:44
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Greg Needel Greg Needel is offline
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FRC #2848 (All-sparks)
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Re: FRC Blog - 2016 Motor Controllers

Quote:
Originally Posted by Ari423 View Post
I'm confused what the point of designing a motor controller for 60 amp continuous is if the largest breaker we are allowed to use is 40 amps. I understand the higher peak, but the I was under the impression that breakers would snap once you get above 40 amps for more than a few milliseconds. It would make sense if these were already being produced and are just now being approved for FRC, but the blog post makes it sound like they were developed specifically for FRC teams.
When someone wants to design a motor controller for FRC, FIRST will provide you a document with their required specifications. One of those requirements is 60 amp continuous operation.

While this may seem like over kill when you do have a 40amp breaker, a factor of safety is a very common thing for equipment like this. It is easy to under estimate the power of 40 amps because we are around it so much on robots but this amount of power density can be extremely dangerous if not done correctly. Back in the "old days" it was not uncommon to see a robot fire or two at a regional event.

We test our controllers to failure at 100amps, to make sure they are as solid and reliable as possible for teams.
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Greg Needel│www.robogreg.com
Co-founder REV Robotics LLC www.REVrobotics.com
2014 FRC World Champions with 254, 469, & 74
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