4 APPLICABLE FUNCTIONS
4.5 Machine diagnosis
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4
Friction vibration estimation function
In the friction vibration estimation function, the friction estimation function estimates the friction of the drive system in the
equipment, and the vibration estimation function estimates the minute vibration level and vibration frequency based on the
data in the servo amplifier. The friction estimation function estimates and detects the static friction (including gravity) and the
dynamic friction of guides and ball screws after operation is performed in any operation pattern. The vibration estimation
function estimates and detects the vibration level both during servo motor operation and at a servo motor stop, and vibration
frequency both during servo motor operation and at a servo motor stop, after operation is performed in any operation pattern.
• If the vibration frequency is extremely low or high, vibration estimation cannot be performed. For example,
low frequency vibrations of several 10 Hz cannot be detected on a low rigidity machine.
• When there is vibration with multiple frequencies at the same time, such as multiple mechanical
resonances, the vibration frequency may not be estimated properly.
• Vibration frequency may not be estimated properly if the torque reaches the limit value. To prevent the
excessive torque vibrations, set a longer acceleration/deceleration time for the command, or slightly
decrease the gains.
• The friction failure prediction function and the static friction failure estimation function cannot be used at the
same time. [AL. 037 Parameter error] occurs if both the friction failure prediction function and the static
friction failure prediction function are enabled at the same time.
Precautions
• It is recommended that the values estimated by the friction vibration estimation function be saved at the start of operation.
By comparing the value estimated by the friction vibration estimation function after the start of operation and with the value
at the start of operation, how much the machine is aged after operation can be learned, which is useful for preventive
maintenance.