Mitsubishi MELSEC-Q QD77MS, User Manual

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11 - 16
Chapter 11 Manual Control
Important
When the inching operation is carried out near the upper or lower limit, use the
hardware stroke limit function (Refer to Section 13.4.4).
If the hardware stroke limit function is not used, the workpiece may exceed the
movement range, and an accident may result.
Precautions during operation
The following details must be understood before inching operation is carried out.
(1) Acceleration/deceleration processing is not carried out during inching
operation.
(Commands corresponding to the designated inching movement amount are
output at operation cycle. The movement direction of inching operation is
reversed and, when a backlash compensation is carried out, first command
corresponding to the backlash amount are output at operation cycle and then
commands corresponding to the designated inching movement amount are
output in the subsequent operation cycles.)
The "
Cd.17 JOG speed" is ignored even if it is set. An error will occur in the
following cases (error code: 301).
(
Cd.16 Inching movement amount) x (A) > ( Pr.31 JOG speed limit value)
Where (A) is as follows.
Operation cycle
0.88 1.77
When the unit setting is PLS. 1125 562.5
When the unit setting is degree and the "
Pr.83
Speed control
10 x multiplier setting for degree axis" is valid.
67.5 33.75
When the unit setting is other than the above. 675 337.5
(2) Set a value other than a "0" in "
Cd.16
Inching movement amount".
If a "0" is set, the operation will become JOG operation (Refer to Section 11.2
"JOG operation").
Operations when stroke limit error occurs
When the operation is stopped by hardware stroke limit error or software stroke
limit error, the inching operation can be performed in an opposite way (direction
within normal limits.) after an error reset.
(An error will occur again if JOG start signal is turned ON in a direction to outside
the stroke limit.)
Inching operation possible
Upper/lower
limit signal
Inching operation
V
Inching operation not possible
ON
OFF