halstrup-walcher PS*3**PL series, Инструкция по эксплуатации

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Instruction Manual PSx3xxPL
23
c) Response of drive in case of manual displacement (readjustment)
If after a correctly finished positioning run (or a manual run to the range limit) during
standstill the PSx3xxPN is displaced by external force opposite to the loop direction
and the release bit (bit 4 in the control word) is set and the readjustment function
(SDO #2047) is enabled, the device will attempt to reach the previously transmitted
target value once again (readjustment). The device does not attempt to readjust if
rotated in the loop direction; it merely sets bit 11 in the status word (“manual
displacement”) and resets bit 0 (“target position reached”). If the loop run is disabled
(SDO #201F is 0), the drive readjusts the position in both directions.
If at standstill the drive continuously looses its position, the attempt to
readjust starts exactly when the actual position is leaving the positioning
window (assumed that all the conditions above are being fulfilled). The
motor power has to be in a valid range at the time when this transition
happens (e.g. bit 4 in the status word is being set). If the motor power is
improper at that time, the readjustment fails and bits
10 (“positioning error”)
and 13 (“motor power was missing”) will become active. If later the motor
power comes back again (after leaving the positioning window), there will
be
no further attempt to readjust. This is to prevent a situation that
suddenly a drive begins to run if motor power is being switched on.
If an ongoing positioning run or manual run is aborted (release bit in the control word
to 0), the drive readjusts the position not before a new run is being sent and finished
successfully.
Deasserting the release bit and/or disabling the readjustment function can completely
disable the readjustment process.
Drives with a brake generally don’t have a readjustment function.
d) Positioning sequence with loop
The length of loop (SDO #201F) has the effect of ensuring that a target value is
always approached from the same direction. This allows, for example, to eliminate the
lash in a driven spindle. The diagram below illustrates the function of the length of
loop:
If the target value is above the current position (actual value 1) and the length of loop
is > 0, the drive runs past the target value by the specified length of loop (run 1a) and
then runs to the target value (run 1b).
If the target value is below the current position and the actual value (actual value 2) is
outside the length of loop, the drive approaches the target value directly (run 2).
If the position always should be approached from the left, the length of loop must be <
0.