On Monday, 14 March 2022 20:21:30 EDT gene heskett wrote: > On Monday, 28 February 2022 20:11:35 EDT gene heskett wrote: > > Greetings Peter; > > > > The 7i76 has, I recall reading, the ability to do analog to digital > > conversions on the first 4 of its inputs. But the full scale range is > > 36 volts if I recall right. I don't recall the bit range, though, > > whether its 8 bit, or 16. > > > > Would it be possible to lower the full scale range to 0-5 volts with > > a > > firmware change? > > > > I have acquired a couple pressure sensors rated at 0-10 psi with a 5 > > volt input, .5 to 4.5 volt outbut and want to use them to monitor, > > and > > control the speed by pwm means as the mister(s) only need 3 or 4 psi > > to do their job if the nozzle is close enough to the cutting face. > > Inch or so. > > And neither of those worked at all, so I bought a couple MAP sensors, > and when I dl the data sheets, I find they have a fairly high src > resistance which limits the outut current to about .1 milliamps, with > an analog voltage swing from typically .2 volts at a very good vacuum, > to around 4.8 volts at 36.? PSIA. No digital, but an analog output. > > Your A/D's on the first 4 inputs of a 7i76D would need more than the .1 > ma at full scale, so my next search then is for a single supply op-amp > running on the motor voltage of 42 volts? (or more) > > Well filtered of coarse. > > > Thanks Peter, take care and stay well.
How about this one: <https://www.analog.com/media/en/technical-documentation/data-sheets/ ADA4522-1_4522-2_4522-4.pdf> running on a filtered leg of the 42 volt motor psu? Cheers, Gene Heskett. -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author, 1940) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
