Siemens 6DS2 124, Руководство пользователя

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ESD Guidelines
©
Siemens AG C79000-D8000-C333-01
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2
When is a Static Charge Formed?
One can never be sure whether the human body or the material and tools which one is using are
not electrostatically charged.
Small charges of 100 V are very common; these can, however, very quickly rise up to 35 000 V.
Examples of static charge:
- Walking on a carpet
up to 35 000 V
- Walking on a PVC flooring up to12 000 V
- Sitting on a cushioned chair up to 18 000 V
- Plastic desoldering unit up to 8 000 V
- Plastic coffee cup up to 5 000 V
- Plastic bags up to 5 000 V
- Books, etc. with a plastic binding up to 8 000 V
3 Important Protective Measures against Static Charge
D Most plastic materials are highly susceptible to static charge and must therefore be kept as far
away as possible from ESDs.
D Personnel who handle ESDs, the work table and the packing must all be carefully grounded.
4 Handling of ESD Modules
D One basic rule to be observed is that electronic modules should be touched by hand only
if this is necessary for any work required to be done on them. Do not touch the
component pins or the conductors.
D Touch components only if
Ć the person is grounded at all times by means of a wrist strap
or
Ć the person is wearing special anti-static shoes or shoes with a grounding strip.
D Before touching an electronic module, the person concerned must ensure that (s)he is
not carrying any static charge. The simplest way is to touch a conductive, grounded item
of equipment (e.g. a blank metallic cabinet part, water pipe, etc.) before touching the
module.
D Modules should not be brought into contact with insulating materials or materials which
take up a static charge, e.g. plastic foil, insulating table tops, synthetic clothing, etc.
D Modules should only be placed on conductive surfaces (table with anti-static table top,
conductive foam material, anti-static plastic bag, anti-static transport container).
D Modules should not be placed in the vicinity of monitors, TV sets (minimum distance from
screen > 10 cm).