Hello folks,
I have been making this clamp on current probe with Hall sensor and it gives me an output of 1mV/Amp.
The problem I have is the amplification of the signal. The purpose is to measure currents in the order of 1-50 amps changing at a speed of about 1000Hz.
I have connected a AD623 like that.
With Rg(ain)=1 K (for gain 100) between pin 1 and 8; The output of IC1a (=input of AD623) remains 0 when I measure a current when I connect to the AD623.
With disconnected inputs the IC1a changes from 0 to 1mV when I measure 1 amp.
Then I diconnected the resistance to ground goiing to IN- of AD623. ... it was getting better: The input of AD623 also changed form 0 to 1 mV when I measured a current of 1 Amp, which is OK. But the output (between Pin 6 and REF pin 5) remains at 0,225 mV even if input (pin 2-3) changes from 0 to 1 mV.
Other Rg's (10K;100K;1M) give same result, exept for Rg 10M: then output changes with 2mV (from 0,299mV to 0.301) for input change of 1mV...
Could somebody help me?
I have been making this clamp on current probe with Hall sensor and it gives me an output of 1mV/Amp.
The problem I have is the amplification of the signal. The purpose is to measure currents in the order of 1-50 amps changing at a speed of about 1000Hz.
I have connected a AD623 like that.
With Rg(ain)=1 K (for gain 100) between pin 1 and 8; The output of IC1a (=input of AD623) remains 0 when I measure a current when I connect to the AD623.
With disconnected inputs the IC1a changes from 0 to 1mV when I measure 1 amp.
Then I diconnected the resistance to ground goiing to IN- of AD623. ... it was getting better: The input of AD623 also changed form 0 to 1 mV when I measured a current of 1 Amp, which is OK. But the output (between Pin 6 and REF pin 5) remains at 0,225 mV even if input (pin 2-3) changes from 0 to 1 mV.
Other Rg's (10K;100K;1M) give same result, exept for Rg 10M: then output changes with 2mV (from 0,299mV to 0.301) for input change of 1mV...
Could somebody help me?