Check Of Servo Unit - Siemens YASKAWA 840DI Maintenance Manual

2.2 Check of Servomotor and Servo Unit
2.2.2

Check of Servo Unit

The following table summarizes how to check the Servo Unit. You need not conduct a daily
check; however, conduct a check once a year at least.
Check item Check timing
Cleaning of body Once per year
and board at least
Loose screw Once per year
at least
Failed parts on body
Once per year
or boards at least
A guide line of parts replacement timing
The following parts become worn or degraded over years. Conduct a periodical check.
As to the Servo Units that we made an overall repair, we are returning them to users with
resetting their drive specific machine data to initial values. Be sure to check drive specific
machine data before starting operation.
Part name
Cooling fan
Smoothing capacitor
Relays
Fuse
Aluminum electrolytic capacitor
on print circuit board
Above table is described supposing:
• Ambient temperature: 30 °C on average
• Load factor : 80% or less
• Availability : 20 hours or less per day
Table 2.2 Check of Servo Unit
Check method
Shall be free from adherent
matters such as dirt, dust, and oil.
Fixing screws shall not be loose
on terminal blocks and connectors
etc.
Shall be free from discoloration
resulting from heat generation,
breakage, wire-break.
Table 2.3 Periodical parts check
Standard
replacement timing
4-5 years
7-8 years
−
10 years
5 years
2-4
Corrective action
Clean with a cloth or
air.
Retighten the screws.
Contact our service
group.
Replacement method etc.
Replace with new one.
Replace with new one (after a check).
Determine after a check.
Replace with new one.
Replace entire board with new one
(after a check).