Mitsubishi Electric MR-JE-_A, Instruction Manual

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7. SPECIAL ADJUSTMENT FUNCTIONS
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(d) Lost motion compensation timing ([Pr. PE49])
You can set the delay time of the lost motion compensation start timing with this parameter. When a
protrusion occurs belatedly, set the lost motion compensation timing corresponding to the protrusion
occurrence timing.
(e) Lost motion compensation non-sensitive band ([Pr. PE50])
When the travel direction reverses frequently around the zero speed, unnecessary lost motion
compensation is triggered by the travel direction switching. By setting the lost motion compensation
non-sensitive band, the speed is recognized as 0 when the fluctuation of the droop pulses is the
setting value or less. This prevents unnecessary lost motion compensation.
When the value of this parameter is changed, the compensation timing is changed. Adjust the value
of Lost motion compensation timing ([Pr. PE49]).
(f) Lost motion filter setting ([Pr. PE46])
Changing the value of this parameter is usually unnecessary. When a value other than 0.0 ms is set
in this parameter, the high-pass filter output value of the set time constant is applied to the
compensation and lost motion compensation continues.
(2) Adjustment procedure of the lost motion compensation function
(a) Measuring the load current
Measure the load currents during the forward direction feed and reverse direction feed with MR
Configurator2.
(b) Setting the lost motion compensation
Calculate the friction torque from the measurement result of (2) (a) in this section and set a value
twice the friction torque in [Pr. PE44] and [Pr. PE45] as lost motion compensation.
Friction torque [%] =
2
|(load current during feed in the forward rotation direction [%]) -
(load current during feed in the reverse rotation direction [%])|
(c) Checking protrusions
Drive the servo motor and check that the protrusions are corrected.