10 - 11
10 Operation
G5-series Linear Motors/Servo Drives With Built-in EtherCAT Communications
10-
2 Pr
e
p
aring
fo
r Op
eratio
n
10
1
0-2-4
Prepar
ing th
e Line
ar Motor
for Oper
ation
Conceptual Diagram of Magnetic Pole Position Estimation
Note
The magnetic pole position estimation function estimates the position of each magnetic pole
by judging the movement direction of the motor several times when the force command
(electric current) is applied.
Precautions for Correct Use
Precautions for Correct Use
•
The magnetic pole position estimation function is executed at the first Servo ON after you turn
ON the power supply. Because the Linear Motor operates during magnetic pole position
estimation, take care so that the motor does not hit the mechanical end stop.
•
The magnetic pole position estimation function may not operate successfully if there is a large
unbalanced load or friction.
•
The values in the objects starting from Magnetic Pole Position Estimation Force Command
Time (3922 hex) through to Magnetic Pole Position Estimation Time Limit for Stop (3927 hex)
are the values set when the magnetic pole position estimation function is started. Changes
made during magnetic pole position estimation are not reflected on these values.
3924 hex
3922 hex
3923 hex
3928 hex
3926 hex
3925 hex
3926 hex
3925 hex
3926 hex
3925 hex
Time
Although the time set in 3922 hex
has not expired, the force command
stops because the amount of motor
movement exceeded the value set
in 3924 hex.
Force Command
Single attempt of judging the motor
movement direction
Time
The force command stops
when the time set in 3922 hex
has expired because applying
the command force at this point
does not cause a sufficient
amount of motor movement.
For Stop Judgement
External Encoder Pulse
Position
Force
After a force command stops, the
motor still runs due to inertia.
Wait until it stops completely.
Depending on the stop
position, the motor may move
in a reverse direction due to
cogging etc. immediately
before it stops.
For Stop Judgement
For Stop Judgement
1st
2nd
This attempt is made several times each
in positive and negative directions.
The number of execution times and the amount of movement
are influenced by external conditions such as the position in
which the function is executed and the friction force.
