142
6 SERVO MOTOR DRIVING
6.3 Indexer mode (idx)
6.3
Indexer mode (idx)
• In the absolute position detection system, rotating the shaft one revolution or more during power-off may
erase a home position. Therefore, do not rotate the shaft one revolution or more during power-off. When the
home position is erased, [AL. 90 Home position return incomplete warning] will occur. In that case, execute
the home position return again.
• The indexer method cannot be used in fully closed systems and linear servo systems. The combination of
the indexer method and fully closed loop system/linear servo system triggers [AL. 37 Parameter error].
• There are the following restrictions on [Pr. PA06 Number of gear teeth on machine side] and the servo
motor speed (N).
When CMX
≤
2000, N < 3076.7 r/min
When CMX > 2000, N < (3276.7 - CMX)/10 r/min
When the servo motor is operated at a servo motor speed higher than the limit value, [AL. E3 Absolute
position counter warning] will occur.
• When the same next station No. is specified as station No. of the current position and a positioning
operation is executed, the motor does not start because the travel distance is judged as "0".
• The "Touch probe function" is disabled for the indexer method.
• In the indexer method, "Position actual value", "Touch probe status", "Touch probe pos1 pos value", "Touch
probe pos1 neg value", "Touch probe pos2 pos value" and "Touch probe pos2 neg value" are always 0.
• The setting of [Pr. PC77 Internal torque limit 2] will be enabled automatically depending on the operation
status. The initial value of [Pr. PC77] is 0.0%. When you use indexer operation, change the value. If the
value remains unchanged, the servo motor coasts.
About indexer mode (idx)
Logic of indexer
The circumference of the load side (360 degrees) can be divided into a maximum of 255 stations. Positioning is executed to a
station selected with "Target point table". The following diagram is an example for when [Pr. PA14] is set to "0".
CW direction
Station No. 2
Station No. 253
Station No. 1
Station No. 254
Station No. 0