Planmeca Compact I, Техническое руководство

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Chapter A - GENERAL & TECHNICAL DATA
Planmeca Compact i A-7
HANDLING PRECAUTIONS FOR PCB’S AND SOFTWARE
Technical Manual
5 HANDLING PRECAUTIONS FOR PCB’S AND
SOFTWARE CHIPS
5.1 Handling printed circuit boards
The circuit boards are well protected against static discharges when they are in the unit. How-
ever, some precautions are necessary when handling the boards since some internal nodes
can easily be damaged by static electricity.This is true especially during low humidity condi-
tions when there is evidently a potential risk of static discharges.
Keeping these few simple rules in mind when handling PCBs or software chips can make a
big difference;
• Grounding wrist-straps are not necessarily required when handling the boards, as long as
you first always touch a grounded exposed metal part in the unit before touching the PCB.
• Place the removed PCB immediately in an antistatic plastic bag. This protects it from later
improper handling. Please note that PCB’s for warranty replacement must be returned to
the factory properly packaged in antistatic plastic bags.
• Never place a removed PCB on a conductive surface or handle it to another person, with-
out touching the surface or person first.
5.2 Handling software Flash-EPROM chips
To avoid static discharge problems the same rules that apply for PCB’s should be followed
when handling software Flash-EPROM chips.
Software Flash-EPROM chips must be stored in their specific anti-static plastic tubes, protect-
ing them also mechanically.
Since the software chip used is a PLCC-type chip, it must be removed only with a proper
extracting tool (see the spare part manual for details). Using any other tool for removal can
seriously damage the socket on the MCB.
Please refer to 5.1 “How to replace/upgrade the software” on page G-20 for details how to
replace the software.