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Unread 13-02-2005, 20:37
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Al Skierkiewicz Al Skierkiewicz is offline
Broadcast Eng/Chief Robot Inspector
AKA: Big Al WFFA 2005
FRC #0111 (WildStang)
Team Role: Engineer
 
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Rookie Year: 1996
Location: Wheeling, IL
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Re: Could a magnetic field around CIMs cause fuses to blow?

Quote:
Originally Posted by jdiwnab
This isn't criticism, only addressing all of your concerns.



The wire that looks like it is going to the gear box is just diconnected from anything. it looks like it is on the gear box but it is just over it. But it does look like it.



The screw is out becuase we were disconnecting things, and we pulled the wire out for that moter.



We see that, and we will check it out when we get back to check the robot. but it would seem odd that several wires would be doing the same thing and creating this problem



I agree that it is far fetched, but when isolating everything, that was about the only thing we could think of at the time. As far as no magnetic field changing, some magnet has to be moving for the moter to go. But it still seems unlikely.

Thanks for you help. All options will be considered. We will look at everyting on Monday when we get back to school.
Believe me there is no moving magnet. All of the KOP motors have stationary, permanent magnets. The Chalupas have two large curved magnets inside the case and glued to the case to keep them from moving. The armatures move when current is applied to them but the magnetic field lines up with the filed of the permanent magnets for the most part. The brushes are doing the appropriate switching to make the fields line up. If nothing else is wrong, the hardware touching the motor(-) screw is enough to cause your problem. I think if you fix the hardware you will be much further along, if not curing the defect altogether. Remember that some controllers are reversed and they are dumping current into the frame. Try this, take you meter and with the robot power removed, check for continuity from the frame to each output terminal on all your controllers. You should measure infinite resistance for every terminal. Then move the probe to measure the +12 volt lead at the output of the main breaker. It should also be infinite. Finally, measure the input to the main breaker (off Please) and you should again have a infinite resistance. If none of these tests are infinite, find where the path exists and remove it. Let me know what you find.
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Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.