Estun pronet series, User Manual

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ProNet Series AC Servo User's Manual
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5.2.4 Automatic Adjustment of the Speed Reference Offset
When using the speed/torque (analog reference) control, the servomotor may rotate slowly even if 0V is specified as the
analog voltage reference.
This happens if the host controller or external circuit has a slight offset (in the unit of mV) in the reference voltage.
The reference offset automatic adjustment mode automatically measures the offset and adjusts the reference voltage. It
can adjust both speed and torque reference offset.
The servo drive automatically adjusts the offset when the host controller or external circuit has the offset in the reference
voltage.
After completion of the automatic adjustment, the amount of offset is stored in the servo drive. The amount of offset can be
checked in the speed reference offset manual adjustment mode (Fn004). Refer to 4.5.3 (2) Manual Adjustment of the
Speed Reference Offset
.
The automatic adjustment of reference offset (Fn003) cannot be used when a position loop has been formed with a host
controller and the error pulse is changed to zero at the servomotor stop due to servolock. Use the speed reference offset
manual adjustment for a position loop.
The zero-clamp speed control function can be used to force the servomotor to stop while the zero speed reference is
given.
Note: The speed reference offset must be automatically adjusted with the servo OFF.
Adjust the speed reference offset automatically in the following procedure.
1. Turn OFF the servo drive, and input the 0V reference voltage from the host controller or external circuit.
2. Press the MODE key to select the utility function mode.
3. Press the INC or DEC key to select the utility function number Fn003.
4. Press the ENTER key to enter into the speed reference offset automatic adjustment mode.
5. Press the MODE key for more than one second, the reference offset will be automatically adjusted.