On Thu, 2008-06-12 at 19:22 -0400, Ed wrote: > Going throuogh the schematics for my CHNC the limit switches and the > home switch have three terminals PLUS MINUS and ZERO. Are these voltage > or polarity dependent or are they simple switches?
The limit and home switches should be Hall effect devices. They have open collector outputs which short the output to ground when they are activated. They should use a 12 Volt supply but are rated for 4.5 to 24 Volts. The output voltage can be any voltage under the supply voltage. Just make sure there is some sort of current limiting below 20 mA on the output. The Z home and limit switches should be Honeywell 103SR's: http://content.honeywell.com/sensing/prodinfo/solidstate/catalog/c20014.pdf The X switches are very similar to these: http://www.cherrycorp.com/english/sensors/ds.htm > Also the turret > encoder shows an A B C and D outputs. Are these binary or BCD and why 4 > lines when 3 would be enough for 8 positions? There are nine conditions to monitor (0 being between tool slots and slot 1 through 8) so the fourth bit is needed. > What voltage to this > encoder? Probably more questions later as I dig into it. Thanks. Ed. The encoder board is setup for a 12 Volt supply. My board has drivers on the outputs instead of open collectors. This chip is similar to the pair on the board: http://www.ti.com/lit/gpn/cd4532b I convert my 12 Volt signals to 5 Volt signals with opto-couplers. -- Kirk Wallace (California, USA http://www.wallacecompany.com/machine_shop/ Hardinge HNC/EMC CNC lathe, Bridgeport mill conversion, doing XY now, Zubal lathe conversion pending Craftsman AA 109 restoration Shizuoka ST-N/EMC CNC) ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
