Instruction Manual PSE2xxDN
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e) Using actual value assessment factors to set the spindle pitch
The PSE object; class 100, instance 1, attribute 16 (numerator factor) and attribute 17
(denominator factor) can be used to represent any desired spindle pitch.
Both factors are set to a value of 400 by default, resulting in a resolution of 0.01 mm
at a spindle pitch of 4 mm.
The denominator factor serves as a simple means of setting the spindle pitch and
resolution.
The numerator factor is primarily used for setting "unlevel" resolutions.
Examples:
Spindle pitch
Resolution
Numerator
factor
Denominator
factor
4 mm
1/100 mm
400
400
1 mm
1/100 mm
400
100
2 mm
1/10 mm
400
20
Numerator and denominator factors may take on values between 1 and 10,000.
f) Drag error
During a positioning run, the device compares the computed target position with the
current actual value. If the difference is larger than the “drag error” value (PSE object;
class 100, instance 1, attribute 5), the device sets the corresponding bit in the status
word. This applies in particular if the target speed cannot be achieved due to external
influences (required torque, motor voltage too low).
g) Aborted run when the master fails
If the connection to the master is interrupted during a positioning run, the master
cannot abort a run that is already underway. Automatically aborting a run in this case
requires an I/O connection with an expected packet rate greater than 0; this
connection must be set up in advance and used for initiating the positioning run. Poll
I/O and bit-strobe I/O may be considered for this connection. Another option would be
to set up a change-of-state/cyclic connection with master acknowledge and an
expected packet rate greater than 0. In this case, the run could be aborted regardless
of how the positioning run had been initiated (i.e., even when using an explicit
connection).
h) Jog run mode
With the help of the jog run bits
in the control word (bit 8 for “jog run to larger values”
and bit 9 for “jog run to smaller values”) a manual run can be performed, provided that
bit 4 (release) is inactive. The release of positioning runs and manual runs (control
word bit 4) and the control word bits for jog runs (bits 8 and 9) cannot be set
simultaneously. Changing the control word bits while running (for example from
positioning run to jog run) aborts a run in the other operation mode.
The step width for a short activation time of a jog run bit can be set via attr. 34. Such
a single step is being executed if one of the jog run bits is being activated. If the jog
run bit is being deasserted before the end of the single step, it will be completed
