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User manual SIPLAC E HF series 2 Operational safety Software Vers ion SR.50x.xx 01/2006 US Edition 2.11 ESD guidelines 91 Always place the modules on a cond uctive sur face (table with an ES D coatin g, conduc tive ES D …
2 Operational safety User manual SIPLACE HF series
2.11 ESD guidelines Software Version SR.50x.xx 01/2006 US Edition
90
2.11 ESD guidelines
2.11.1 What does ESD mean?
Almost all of the modules in use today are equipped with highly integrated MOS blocks and com-
ponents. The manufacturing techniques used mean that these electronic components are ex-
tremely sensitive to overvoltage and thus to electrostatic discharge.
The abbreviation for such modules is 'ESD' (Electrostatic Sensitive Device). ’ESD’ is used inter-
nationally. The following symbol on cabinet rating plates, racks or packaging indicates that com-
ponents which are sensitive to electrostatic discharge have been used and thus that the modules
concerned are also touch-sensitive.
ESDs can be destroyed by voltages and power levels that are far below the level
that can be perceived by humans. Such voltages occur if a person touches a com-
ponent or module without earthing themselves. Components that are exposed to
such overvoltages do not generally appear to be defective immediately - incorrect
behavior starts after the component or module has been in operation for some time.
2.11.2 Important measures to protect against static charging
Æ Most plastics can easily become charged and must therefore be kept away from at-risk com-
ponents.
Æ Always ensure that people, the workplace and packaging are safely earthed when handling
electrostatic sensitive components.
2.11.3 Handling ESD modules
Do not touch electronic modules unless it is absolutely essential to do so in order to carry out other
work. If it is necessary, make sure that you do not touch the pins or printed conductors when you
pick up flat modules.
Do not touch components unless
Æ you are constantly earthed by an ESD wrist strap or
Æ you are wearing ESD shoes or ESD shoe earthing strips on an ESD floor.
Always discharge yourself before you touch an electronic module. To do this, simply touch a con-
ductive and earthed object immediately before you touch the module (such as unpainted parts of
a switch cabinet, a water pipe, etc.).
Do not allow modules with chargeable and highly insulating materials to touch one another, e.g.
plastic films, insulating table surfaces or items of clothing made from synthetic fibers.
User manual SIPLACE HF series 2 Operational safety
Software Version SR.50x.xx 01/2006 US Edition 2.11 ESD guidelines
91
Always place the modules on a conductive surface (table with an ESD coating, conductive ESD
foam, ESD bag or container).
Do not bring modules near visual display units, monitors or televisions. Keep them at least 10 cm
away from the screen.
2.11.4 Measurements and modifications to ESD modules
Do not take measurements on the modules unless the following conditions are fulfilled:
– the measuring device is earthed (e.g. via PE conductors) or
– you discharge the measuring head just before taking measurements with a potential-free
measuring device (e.g. by touching an unpainted metal part of the controller casing).
Æ Always use an earthed soldering iron if you carry out any soldering work.
2.11.5 Dispatching ESD modules
Æ Always store modules and components in conductive packaging (e.g. metallized plastic bags
or metal sleeves) and dispatch them in conductive packaging.
If the packaging is not conductive, place the modules in a conductive envelope before pack-
aging. Use conductive expanded rubber, ESD bags, domestic aluminum foil or paper, for ex-
ample. NEVER use plastic bags or film. 2
Æ If the module has integral batteries, ensure that the conductive packaging does not touch or
short-circuit the battery terminals and, if necessary, first cover the terminals with insulating
tape or material.
2 Operational safety User manual SIPLACE HF series
2.11 ESD guidelines Software Version SR.50x.xx 01/2006 US Edition
92