6-9
6-3 Overrun Protection
OMNUC G5-Series AC Servo Drives Users Manual (Built-in MECHATROLINK-II communications type)
6
Applied Functions
6-3 Overrun Protection
The function detects an overrun limit error (Alarm No.34.0) and stops the Servomotor if the
motor exceeds the allowable operating range set by the Overrun Limit Setting (Pn514) with
respect to the position command input.
The function can also prevent the Servomotor clash into the machine edge due to its vibration.
Operating Conditions
The overrun limit works under the following conditions.
Conditions for Clearing the Position Command Input Range
The position command input range will be cleared to zero under any of the following conditions.
When the power supply is turned ON,
While the position error is cleared. This includes the case of Servo-OFF, and when the error
counter is cleared due to deceleration stop by the drive prohibit input.
When a trial operation via USB communication starts up and when it ends.
During speed control or torque control,
When the position data is initialized. This includes the cases of a component setup request, an
origin return, a coordinate system setup, and an adjustment command.
Precautions for Correct Use
Note this function is not intended to protect against abnormal position commands.
When this function works, the Servomotor decelerates according to the Stop Selection for Alarm
Detection (Pn510) and stops. Take this deceleration operation into account when you set the
overrun limit (Pn514). Otherwise, the loads during deceleration may hit and cause damage to the
machine edges.
The function is disabled when the communications frequency characteristic function is enabled.
Parameters Requiring Settings
Conditions
Operating Mode POSITION CONTROL mode, FULL CLOSING CONTROL mode
Others
• Servo-ON state
• The functions other than control parameters are set correctly. (i.e., torque limit,
etc.) This includes the torque limit. The motor operates normally without any
failures.
Parameter
number
Parameter name
Description
Reference page
Pn514
Overrun Limit Setting
Sets the Servomotor's allowable operating range for
the position command input range.
