Thread: Current Measurement
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Unread 12-01-2009, 00:07
writchie writchie is offline
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Re: Current Measurement
Quote:
Originally Posted by DeepWater View Post
Thanks, I wasn't really thinking about spikes. Where did you find that they are good for 500% over their measrement range?

We are interested in current measurement mostly for use in traction control so I am guessing large spike due to stalled drive motors may not be a huge problem this year. I am assuming that a jammed or locked mechanism driven by a CIM would stall the motor long enough for the breaker to kick out but I could see that brief large spikes would occur when say a CIM shifts from full forward to full reverse. Any thoughts as to if these Phidgets would smoke on a brief spike like this or just max their reading?
See the datasheet for the allegro sensors. 500% will protect them from damage. The way these work is that the sense terminals go through the IC package so that the magnetic current in the wire is sensed by hall effect inside the package. There are electically isolated. I think they can withstand 500% overload indefinitely.