Mitsubishi Electric MELSERVO-JN Series Instruction Manual page 313

12. SERVO MOTOR
12.2.7 Life
Service lives of the following parts are listed below. However, the service lives vary depending on operating
methods and environmental conditions. If any fault is found in the parts, they must be replaced immediately
regardless of their service live. For parts replacement, please contact your local sales office.
When the servo motor is operated at the rated speed under the rated load, replace the bearings in 20,000 to
30,000 hours as a guideline. However, this service life varies depending on the operating conditions. The
bearings must be replaced if unusual noise or vibration is found during inspection.
12.2.8 Machine accuracies
The following table indicates the machine accuracies of the servo motor around the output shaft and mounting
(except the special purpose products).
Part name
Bearing
Encoder
Accuracy [mm]
Runout of flange surface about output
shaft
Runout of fitting outer diameter of flange
surface
Runout of output shaft end
Reference diagram
Life guideline
20,000 to 30,000 hours The Life guideline field gives the reference time.
If any fault is found before this time is reached,
20,000 to 30,000 hours
the part must be changed.
Measuring position
a)
b)
c)
b) c)
a)
12 - 10
Remark
Flange size
Less than 100
0.05
0.04
0.02