Mitsubishi MELSEC-Q QD77MS, User Manual

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Chapter 13 Control Sub Functions
(5) A warning "Deceleration/stop speed change (warning code: 500)" occurs
and the speed cannot be changed in the following cases.
• During deceleration by a stop command
• During automatic deceleration during positioning control
(6) A warning "Speed limit value over (warning code: 501)" occurs and the
speed is controlled at the "
Pr.8
Speed limit value" when the value set in
"
Cd.14
New speed value" is larger than the "
Pr.8
Speed limit value".
(7) When the speed is changed during interpolation control, the required speed
is set in the reference axis.
(8) When carrying out consecutive speed changes, be sure there is an interval
between the speed changes of 100ms or more.
(If the interval between speed changes is short, the QD77MS will not be
able to track, and it may become impossible to carry out commands
correctly.)
(9) When a speed change is requested simultaneously for multiple axes, change
the speed one by one.
Therefore, the start timing of speed change is different for each axis.
(10) Speed change cannot be carried out during the machine OPR. A request
for speed change is ignored.
(11) When deceleration is started by the speed change function, the deceleration
start flag does not turn ON.
(12) The speed change function cannot be used during speed control mode,
torque control mode or continuous operation to torque control mode.
Refer to Section 12.1 "Speed-torque control" for the speed change during
speed control mode or continuous operation to torque control mode.
[3] Setting the speed change function from the PLC CPU
The following shows the data settings and sequence program example for
changing the control speed of axis 1 from the PLC CPU. (In this example, the
control speed is changed to "20.00mm/min".)
(1) Set the following data.
(Use the speed change time chart shown in section (2) below as a
reference, and set using the sequence program shown in section (3).)
Buffer memory address
Setting item
Setting
value
Setting details
QD77MS2
QD77MS4
QD77MS16
Cd.14 New speed value 2000 Set the new speed.
1514+100n
1515+100n 4314+100n
4315+100n
Cd .15
Speed change
request
1 Set "1: Change the speed". 1516+100n 4316+100n
n: Axis No.-1
: Refer to Section 5.7 "List of control data" for details on the setting details.