Maintenance, Preventive maintenance – Lincoln Electric INVERTEC SVM129-B User Manual
Page 27
MAINTENANCE
D-3
D-3
INVERTEC® STT® & STT® II
PREVENTIVE MAINTENANCE
1. Perform the following preventive mainte-
nance procedures at least once every six
months. It is good practice to keep a pre-
ventive maintenance record; a record tag
attached to the machine works best.
2. Remove the machine wraparound cover
and perform the input filter capacitor dis-
charge procedure (detailed at the begin-
ning of this chapter).
3. Clean the inside of the machine with a
low pressure airstream. Be sure to clean
the following components thoroughly.
• Power Switch, Driver, Protection, and
Control printed circuit boards
• Power Switch
• Main Transformer
• Input Rectifier
• Heat Sink Fins
• Input Filter Capacitors
• Output Terminals
• Lower base compartment
4. Examine capacitors for leakage or oozing.
Replace if needed.
5. Examine wraparound cover for dents or
breakage. Repair as needed. Cover must
be kept in good condition to assure high
voltage parts are protected and correct
spacings are maintained.
6. Check electrical ground continuity. Using
an
ohmmeter,
measure
resistance
between either output stud and an unpaint-
ed surface of the machine case. Meter
reading should be 500,000 ohms or more.
If meter reading is less than 500,000
ohms, check for electrical components that
are not properly insulated from the case.
Correct insulation if needed.
7. Replace machine cover and screws.