PSx3xxDP Instruction Manual
13
6
Start-up
6.1
Setting the reference position
Once it has been installed, the PSx3xxDP must be moved to the reference position, either
via the jog keys or with a positioning command
. The ‘set reference position' command
(see section entitled ‘Command byte configuration’) is used to set the internal position of
the PSx3xxDP to zero. This position is saved by the instrument and used as a reference
for all positioning data and ranges.
Position 0000 was assigned to the reference point for firmware version 6 and lower.
Beginning with firmware version 7, however, the reference position is assigned the value
of the module target position. The reference position and assigned position are both
permanently stored in the instrument.
6.2
Positioning sequence
The PSx3xxDP distinguishes between the following steps of a positioning sequence
(It is assumed that all target positions are approached via forward motion.)
1.
New position value is larger than the current value: position approached directly.
2.
New position value is smaller than the current value: the instrument reverses by the
length of the reference loop and approaches the exact position after resuming forward
motion.
3.
New position value after reverse run (no reference loop): the instrument always
approaches the position by moving forward the length of the reference loop; if
necessary, it will first reverse by one rotation.
Once the target position has been reached, the instrument compares it to the internal
absolute encoder status. If a discrepancy is detected, the instrument then sets the
“positioning error” status bit.
The length of the reference loop and the direction can be configured when setting
parameters or by using the parameter module.
6.3
Positioning sequence (without reference loop)
The “positioning without a reference loop” mode is used primarily for moving the small
distances involved in fine adjustments. In this case, each position is approached directly.
This does NOT eliminate any play present in the spindle in question. The PSx3xxDP
internal gear backlash does not play a role in this case, as position data are acquired
directly at the output shaft.
Underwater usage of the PSW is not allowed.
Summary of Contents for PS*3**DP series
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