Quote:
Originally Posted by MechEng83
That wasn't actually a serious question, but thanks for the answer! For the Talons we used on our drive train, we experimented with using a wire coiled around one of the wire leads and got some values in a custom circuit. I'm not sure of all the details, our electrical mentors worked on it.
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It sounds like your team measured the electromagnetic field around the wire with a circuit that works like a current sense transformer. It doesn't actually connect to the circuit it merely robs some of the magnetic field around the wire (which is generally there as long as current flows) and converts it to something you can measure. That might let you skate on the FRC rules about getting in the circuit path between the electronic speed control and the motor. Plus when done with a current sense transformer you bypass the grounding issues as one leg of the output can be tied to that electronics ground with little impact on the electronic motor control or the motor. Using a current sense transformer it's important to note that measuring AC and DC currents require different considerations.
There are Allegro hall effect sensors that can measure circuit current if you dig around they were recommended up on ChiefDelphi before (oddly almost precisely 3 years ago):
http://www.chiefdelphi.com/forums/ar...p/t-87568.html
I am interested if these are legal in FRC in competition. However that might be a side track for this topic.