8.5.3 Functional check
Consider customer complaints, if any, when carrying out functional checks.
The resulting diagnosis must be taken into account in addition to the normal Maintenance check.
What to check
Visual Check:
Covers
1.
LCD
Spool pin
2.
Function
3.
Needle
Power cable
4.
Foot control cable
5.
Switch machine on and let it run
Functions to test with machine
6.
switched on
7.
Functioning of connection
(Remove covers)
8.
Single strand cable
9.
Rough visual check of settings
10.
Drive motor
Smooth running of the machine
11.
– mechanical ease of
movement
BERNINA International AG · Seestrasse 161 · CH-8266 Steckborn · Switzerland
What to check for specifically
• Scratch marks and signs of having dropped the
machine
• Tears and cracks
• Clearance/gap widths
• Main switch
• Correctly attached
• Bent
• Blunt
• of low quality
• wrong system
• Damaged insulation
• Loose contacts / interruptions
• Squashed cables
• Connectors
• Listen for unusual noises or noise level
• Foot control adjustment
• Stepping motors
• Sewing light
• Keys and buttons
• Stitch width and stitch length adjustment
• Screen / LCD
• Threading process
• Foot control
• Damaged insulation
• Loose contacts / interruptions
• Squashed cables
• Connections
• Needle distribution
• Needle-/hook distance
• Feed-dog synchronization (lift and advance timing)
• Main shaft-/base shaft synchronization
• Bearing play
• Mechanical ease of movement (smooth running)
• Drive belt
Shaft and axes play:
• Main and base shaft
• Thread take-up crank
• Needle bar support / needle bar
• Bevel gears
• Bobbin carrier / hook
• Drive belt tensions
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