Hi Seb, If you have room for a relay or small contactor big enough to operate the motor, then I'd vote for the classic latching circuit.
This has some examples, but it's in the form of a quiz: http://www.ibiblio.org/kuphaldt/socratic/output/acmcc.pdf That way lots of things can stop the motor, but if you want it to start again, you have to go back to the start button. Very safe. How much is the saw *with* the girl? Kim On 06/22/2011 11:31 AM, Sebastian Kuzminsky wrote: > I'm reviving an old band saw that someone donated to our hackspace. It > looks a bit like this one, but way older and junkier, and without the girl: > > http://www.oceanmachinery.com/images/kmt-band-saw.jpg > > It has an automatic shut-off switch that triggers when the saw has cut > all the way through the workpiece, like a bottom limit switch -- it just > opens the circuit that powers the motor. > > It used to have a toggle switch on the front that would let you turn the > motor on (if the saw was up off the bottom limit switch), but that > on/off switch was dead when we got it. > > We removed the broken on/off switch and jumpered the power cable there > instead, so now whenever you plug it in to the wall outlet (and lift the > saw off the bottom limit switch), the motor turns on. > > We got the machine running and cleaned it up, and now it's time for a > new on/off switch. > > I think I want a button that latches on, can be easily unlatched by > punching it (like an e-stop button), and that unlatches automatically > when the bottom limit switch (or the fuse) opens the circuit. > > Any suggestions? > > ------------------------------------------------------------------------------ Simplify data backup and recovery for your virtual environment with vRanger. Installation's a snap, and flexible recovery options mean your data is safe, secure and there when you need it. Data protection magic? Nope - It's vRanger. Get your free trial download today. http://p.sf.net/sfu/quest-sfdev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
