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9 Servo Parameter Objects
G5-series Linear Motors/Servo Drives With Built-in EtherCAT Communications
9-8 Linear Motor Objects
9
• Set the command force for a single force command during magnetic pole position estimation.
• This setting is enabled only when the Magnetic Pole Detection Method (3920 hex) is set to 2
(Magnetic pole position estimation).
Precautions for Correct UsePrecautions for Correct Use
• If this object is set to a small value, the motor may not show its full performance, resulting in a
poor detection accuracy or a Magnetic Pole Position Estimation Error. If the motor is subjected
to a large load or resistance, set a sufficiently large command force.
• The magnetic pole position estimationn accuracy may be improved by increasing the set value
in the Magnetic Pole Position Estimation Force Command Time (3922 hex) or Magnetic Pole
Position Estimation Force Command (3923 hex). However, if you set a large value in the
Magnetic Pole Position Estimation Force Command Time (3922 hex), an Overload Error (Error
No. 16.0) will occur depending on the Magnetic Pole Position Estimation Force Command
(3923 hex) setting.
• The actual command force is limited with the maximum allowable force of motor.
• Set the pulse width to be judged as zero movement during magnetic pole position estimation.
• It will be judged as zero movement if the number of motor movement pulses is less than the set value
when a force current is applied with the conditions set in the Magnetic Pole Position Estimation Force
Command Time (3922 hex) and the Magnetic Pole Position Estimation Force Command (3923 hex).
• Although setting a smaller value contributes to the reduction in the amount of movement during
magnetic pole position estimation, it may result in a poor detection accuracy. As a guide, set the
number of pulses corresponding to one degree of electrical angle.
• This setting is enabled only when the Magnetic Pole Detection Method (3920 hex) is set to 2
(Magnetic pole position estimation).
Calculation formula for the number of pulses corresponding to one degree of electrical
angle (for linear system)
Number of pulses corresponding to one degree of electrical angle (for linear system) = Magnetic
pole pitch [0.01 mm] x 10,000/Feedback scale resolution [0.001 µm]/(360 [degrees]/1 [degree])
3923 hex
Magnetic Pole Position Estimation Force Command
Setting
range
0 to 300
Unit
%
Default
setting
50 Data
attribute
B
Size 2 bytes (INT16) Access RW PDO map Not possible
3924 hex
Magnetic Pole Position Estimation Maximum Movement
Setting
range
0 to 32,767
Unit
Pulse
Default
setting
100 Data
attribute
B
Size 2 bytes (INT16) Access RW PDO map Not possible