Parker Hannifin VIX500IM Stepper Machine User Manual


 
VIX IM MICROSTEPPER INDEXER DRIVE USER GUIDE
90
Settle Time
When Position Maintenance is enabled all moves will track actual position against
commanded position. Position Maintenance allows the in-position signal to be held off for a
settle-time, the value of which can be programmed in the command parameters.
Speed Of Correction
Once a move has been completed and the controller decides position maintenance
correction is required, it will move the motor at a fixed speed of 1rps.
Example of Position Maintenance
The following code illustrates how position maintenance is implemented. The example is
based upon a motor resolution of 4000 steps per rev and a 1000 line encoder giving 4000
counts per rev.
1DECLARE(TRIAL)
1MOTOR(X,X,4000,X,X,X,X) ;X is set depending upon the application
1TRIAL:
1ON
1R(EI) ; check encoder is set to quadrature operation
1POSMAIN0(20,3,0) ; set-up position maintenance, dead band of 20 encoder
steps, output 3 to be used, no programmed settle time
1D40000 ; program distance, 10 revs
1V5 ; set velocity to 5 rev/s
1A10 ; set acceleration to 10 rev/s/s
1POSMAIN1 ; enable position maintenance
1POSMAIN ; check status of command
1W(PA,0) ; set absolute position to zero
1G ; start the move, motor turns 10 revs
1R(PA) ; read position
1END
Following the G command the system will attempt to correct any final position error at the
end of the move.
Note: When the command is armed output 3 will come on with the motor in position and
stationary. When the G command is given output 3 will turn off until the motor is back in
position within the dead band.