Parker Hannifin VIX250IM Stepper Machine User Manual


 
6. COMMAND REFERENCE 155
POSMAIN
Position maintenance
Syntax aPOSMAINon/off(dead_band_range,output,settletime)
Description POSMAIN must use an encoder connected to X2 to monitor the systems
actual position. The command enables position maintenance. The on/off
parameter takes the values of 1 for ON and 0 for OFF. With position
maintenance enabled, if the motor shaft stops within the dead band range
for the optionally specified settle time then the indexer will regard the move
as having been completed. If the motor shaft is stationary outside of the
dead band range, position maintenance will attempt to move the motor shaft
to its target position.
Status bit 17 will be set while executing a position maintenance move.
The optional parameter output specifies a user output that will be latched
ON when a corrective move is made. The output will be turned OFF when
the next G (go), GH (go home), any ON command or Z (reset) command is
received, and status bit 17 will be reset.
The optional parameter settletime specifies how long in milliseconds that the
indexer will wait after motion has ceased, before checking the feedback
encoder. Motion has ceased when the motor has been commanded to stop
and the in-position timer has timed out. The in-position signal will only be set
(high) after the in-position time and the settle-times have lapsed and the
motor shaft has been positioned within the deadband.
For more information on POSMAIN refer to the Position maintenance
section in Control of ViX Drives.
Parameter ranges are:
Parameter Range Units Defaults
On/off 1 ON, 0 OFF refer to table 0
Deadband Range 0 to 32767 of distance units
for enabled
10
Output 0 to 3
(0 = no output)
commands in
section 4.
0
Settle time 0 to 65535 milliseconds 0
Note: dead band range is measured in encoder count units as a +/- band, consequently a
dead band of 10 will be equivalent to ±10 or 20 units wide.