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I was wondering if anyone would have a calculation to establish a value for my "deadband" . I have read the section in the integrators manual and see the formula if using encoders, but we have resolvers on our machine, and i was not sure how to go about the math to establish a starting point.


Thanks

Rick

LAIR82 wrote:
Is there a problem with zero?

If so, just increase it until the problem goes away.

Deadband sets how much either way of my commanded position it is allowed to deviate from correct?

LAIR82 wrote:
Not quite. It sets a band around the setpoint where the controller doesn't even attempt to correct the position error.

LAIR82 wrote:Take whatever your resolver converter produces when converted to axis units
and multiply by 1.5 for a starting value. So, if you have 4096 counts/rev and
a 5 TPI leadscrew, then your resolution is 1/(4096 * 5) = 0.0000488 inch.
So, a good starting value would be 7.32E-5
You want to keep this value as small as possible while suppressing annoying
servo dither. If it is too large, it adds a discontinuity in the servo transfer
function as it crosses zero, and can make the loop unstable.

And, of course, if you DON'T have any dither, then use zero.

Jon

I set it to zero and started from there going down on the count until it got "nervous" and then backed off a little bit. Nice and quiet now and no jitter on the display. The servo was humming before and I think it was "hunting" and I just did not realize what it was actually doing.


Thanks


Rick