Cleaning; Warning: Dangerous Voltage Levels - Bernina 330 Service And Maintenance Manual

1.2 Cleaning

Remove the covers and clean.
Electrostatic charging may occur during cleaning. To prevent this, use antistatic office-equipment cleaning
agents.
We use and recommend BASF's SURFACE CLEAN surface cleaner
It forms a protective film against static electricity, and is suitable for both plastic and metallic surfaces.
Attention!
Never use alcohol, petrol, spirits or any corrosive fluids, or abrasive pastes!
Inside parts:
•
Dust, lint, thread and fabric remnants can accumulate inside the machine behind the covers and may
lead to malfunctions.
Area of the head frame:
•
Thread take-up lever (joints), needle bar, needle bar support.
•
Main shaft (behind the balance piece), synchronisation disc.
•
Between the upper thread tension discs, and in the total thread passage ways and guides.
Area of the free arm and base:
•
Bobbin carrier (under the tension spring).
•
Feed-dog
•
Hook
•
Base shaft (feed and lifter cams).
Area of the transmission:
•
Main motor (carbon dust).
•
Toothed belt drive and motor pulley.
•
Hook drive mechanism.
•
Console transmission.
Area of electronics:
•
All sensors / light barriers / switches / electronic group of parts.

1.3 Warning: Dangerous voltage levels!

Important!
The power connection, the main switch, the PCBA (power) and the power cable all carry
dangerous voltages.
Therefore always disconnect the machine from the power supply before starting any
work on the machine. This applies unless otherwise instructed where required.
Note:
The capacitors require 30 seconds to discharge after the power supply has been switched off. We
recommend waiting for the complete discharging of the capacitors before starting any servicing work on the
PCBs.
BERNINA International AG · Seestrasse 161 · CH-8266 Steckborn · Switzerland
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