Any home built CNC'ers - Mach3 E-stop
On 18-May-15 5:21 PM, snafu wrote:
I've got a lashed together 3 axis mill/router.
I replaced the Dremel tool with a 12V DC spindle.
Now the limit switches (wired to the E-stop input) false triggers when
the spindle is loaded rapidly.
I've bonded the spindle supply gnd the motor/controller ground.
I've placed a 0.1uF cap across the E-stop loop at the controller.
I've placed a fly-back Schotky diode across the spindle motor terminals.
By configuring the E-stop for an active low input and shorting out the
switch loop I've proved its the spindle causing the false E-stop signals.
I currently run the E-stop loop open circuit with the switches closing
when the axes travel too far.
Can I simply swap the E-stop pin configuration to active low and run the
axis limit switches normally closed (opening when they are hit?
Any gotchas?
Thanks
I figure a follow up post is in order..........
I tried lots of different things, filter caps, changing pull up resistor
values etc.
I could not get Mach3 to work with the switches set in a normally closed
manner & gave up on that route.
What did work was using s shielded 2 wire cable. I kept the shield
separate from the grounded switch wire, commoning them only at the
interface pcb. Now its all good (for now!).
Thanks for the motivating suggestions gents.
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