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Re: Current Sensor
This is a kind of on subject question. I was reading a white paper on making current sensors by using an Op amp to get usable input voltages from the voltage drop across the fuses. The paper was written by Mr Lewis, mentor of team 811, back in 2002. I like the design, but after exhaustive research, the only acquireable parts are surface mount. Not a DIP in stock at the approved vendors or even some brokerage houses. He mentions the resistance of the 20 amp fuses at about 9 milliohms and the 30 amp at about 6 milliohms. I don't have a meter that will get me readings that low. Does any body have a resistance value for the 40 amp breakers or a test rig to get there under load. If I do the circuit with surface mount I don't want to take the gain resistors on and off to get a usable range. Thanks in advance.
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