Mitsubishi Electric M800VW Series Programming Manual page 799

M800V/M80V Series PLC Programming Manual (2/2)
14 PLC Help Function
14.30 Real-Time Tuning 2 (Rapid Traverse Time Constant)
Timing for switching to optimum time constant
When this function is enabled, the timing for switching the target acceleration/deceleration time constant to the optimum time
constant is after the smoothing zero of the target axis for switching the time constant. At this time, the acceleration/
deceleration time constant of all target axes are switched internally.
The operation example is given below.
Command
speed
Speed waveform
Inertia estimate
processing
Estimated inertia acquisition
request
Optimum time constant
calculation processing
Acceleration/deceleration
time constant switch
processing
Acceleration/deceleration
time constant
(a) Do the inertia estimation processing to calculate the estimated inertia ratio when completing the interpolation of posi-
tioning operation in the drive. The calculated estimated inertia ratio is retained its value until next inertia estimation
processing.
(b) When the speed command from the NC becomes smoothing zero, the NC gives the acquisition request of estimated
inertia ratio to the drive to obtain the estimated inertia ratio.
(c) When the estimated inertia ratio this time and the time constant calculation completed last time are different from the
estimated inertia ratio last time, the optimum time constant calculation processing is performed to obtain the optimum
time constant.
(d) When the optimum time constant calculation processing is completed and when the target axis for switching acceler-
ation/deceleration time constant is not in operation, the optimum time constant switch processing is performed.
(e) When the acceleration/deceleration time constant switch processing is completed, the speed command followed by
the acceleration/deceleration time constant is output from the NC.
IB-1501668-B
FB speed
(a)
(b)
(c)
778
(d)
(e)
Time
Time
Time
Time
Time
Time