Poul-Henning Kamp wrote: > In message <[EMAIL PROTECTED]>, Bruce Griffiths writes: > > >> Offset drift is significantly higher than for other sensors. >> > > On the LTSR they've pinned out the reference, so you can calibrate > the offset out. I've done it, it's trivial. > > The dc offset for zero input current is primarily determined by the reference voltage however it isnt the only source of offset or drift drift. The hall sensor, the amplifiers and the magnetic circuit all contribute to drift. None of these effects can be compensated by having the reference available. Not having a demagnetising winding for the magnetic core is a major drawback should the core be magnetised as a result of overload or other accidents. >> LEM also make dc fluxgate current sensors with 1ppm linearity and 50ppm >> accuracy. >> > > And I belive, they also make money on those. > > For my needs (a 12 bit ADC) calibration is just fine. > > As always there is a cost/complexity/accuracy tradeoff.
Bruce _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
