On 2010-07-31, Ignoramus28671 wrote:
On 2010-07-31, Karl Townsend wrote:

What I was thinking is to add a button sized potentiometer called
"speed override", where I can make everything run faster or slower.

i


This is EXTREMELY handy. No way do you get feeds just right on one of parts.
I've got a spindle speed pot on all my machines also. If you've got manual
machine experience you can dial in proper feeds and speeds in just a few
seconds. In my case, I've never used a speed feed calculator.

OK thanks. I do not know if Jon's PPMC can take in analog signal, I am
unaware of whether it is true or not. But if it could, it would be
nice. I will check with him.

Have it put out more than nominal speed voltage and run the
output voltage through a pot on the way to the VFD's input. That way
you can go from your selected amount above the nominal speed down to
zero speed (or perhaps add a fixed resistor on the bottom leg of the pot
so you don't quite get down to halted).

Of course -- if the system is monitoring the speed via the
spindle encoder, it will figure that something is wrong -- so prepare
for disabling the speed monitoring when using the pot.

Enjoy,
DoN.

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