On Friday 14 December 2012 03:11:46 Gene Heskett did opine: > On Friday 14 December 2012 02:56:07 Tim James did opine: > > Google Allegro ACS712 Current Sense IC, this would do what you want. > > Not without additional gain, Tim. Its an AC output, with the quiet > output sitting at Vcc*0.5. Sensitivity for the most sensitive one is > .185 mv/A.
And I screwed that royally, its 185mv/A, not .185mv. Way too late. Or too early... > Thanks, that is an approach I hadn't considered. I'll look in the > morning to see if they have something more sensitive. I'd like to see > a unidirectional output in the 1 volt per amp or more range. > > > Sent from my BlackBerry® wireless device > > > > -----Original Message----- > > From: Gene Heskett <ghesk...@wdtv.com> > > Date: Fri, 14 Dec 2012 01:34:37 > > To: Enhanced Machine Controller (EMC)<emc-users@lists.sourceforge.net> > > Reply-To: "Enhanced Machine Controller \(EMC\)" > > > > <emc-users@lists.sourceforge.net> > > > > Subject: [Emc-users] Thoughts on an electronic fuse > > > > Greetings all; > > > > The thought has occurred to me that an alternative to using the iffy, > > and because the pid.error is subject to slight variations due to non- > > linearities of speeds, making any comp type trip off have a best guess > > as to when to activate, seems like a SWAG at best. > > > > So, how about a small current transformer around one of the wires > > leading to the real fuse? Their consistency is good enough the power > > folks drive their usage meters from them at the heavier load sites. > > > > That then needs a way to get it into the machine via a spare pin on > > the cnc2pc C1G card. E-Stop in most likely. > > > > Does anyone have a URL where I could find a toroid suitable for > > developing a logic level output from a 3 amp current flow, or the math > > to wind my own? > > > > Thanks. > > > > Cheers, Gene > > Cheers, Gene Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> is up! BOFH excuse #297: Too many interrupts I was taught to respect my elders, but its getting harder and harder to find any... ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
