Originally Posted by JRoque  Tom, do a search here for limit switch topic; there's quite a bit on the subject. Here's one I participated on. In my case, I went down to Radio Shack and bought a few of those alarm magnetic switches. You put the magnet (it has double-sided tape) on the moving side and the reed switch fixed on the axis. Depending on what you use to control the machine it might be as easy as a direct connection to your parallel port input lines. I had to use some lowpass filters which are nothing more that a resistor and a ceramic capacitor - also available at RS - to cut out some noise generated by the drives.
JR |
How is the lowpass filter constructed? What are the values of the components?