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User Manual SIPLAC E HF Series 2 Operational safety Software Vers ion SR.505.xx 05/2004 US Edition 2.11 ES D guidelines 85 2.1 1 ESD g uidelines 2.1 1.1 What does ESD mea n? Almost a ll of the m odules in use today are e…

2 Operational safety User Manual SIPLACE HF Series

2.10 Lock out and tag out procedure Software Version SR.505.xx 05/2004 US Edition

– To determine how much training to provide for each worker, the employees are divided into

three groups. Each group has its own level of training.

– Authorized employees.

– These workers actually install the locks and tags and do the preventive maintenance or service

work. So they must know the most about controlled energy. First, they must be able to recog-

nize all energy sources and measure the amount of energy. Authorized employees must look

for energy sources out of the realm of the obvious. These energy sources include electrical,

mechanical, hydraulic, pneumatic, chemical, thermal and gravitational. Once these workers

can recognize all energy sources they must be taught how to isolate, control, and release the

energy without any risk.

– Affected employees

– These are workers who operate the machinery or equipment that may be de-energized. Other

employees who may be affected include those who work in an area that contain equipment that

may be locked/tagged out. These employees have to be instructed about the nature of the en-

ergy control program. They must know why lock/tag out is important, what tags and locks look

like and why they must not remove tags or locks.

– All others

– As the name implies, any employee who is not affected or authorized fits into this category.

There employees include office personal, managers, and upper management. Although they

do not have a direct relationship to the machinery being locked or tagged, they have to receive

some training.

– To evaluate the lock/tag out procedure, the safety department will conduct periodic inspections.

As part of the inspection the safety department will document that all facets of the procedure

are followed. The safety department will follow up with formal classroom review or retraining of

the LO/TO procedure.

2.10.6 Review

This procedure will be reviewed and amended as required, and at least once a year.

User Manual SIPLACE HF Series 2 Operational safety

Software Version SR.505.xx 05/2004 US Edition 2.11 ESD guidelines

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.

2 Operational safety User Manual SIPLACE HF Series

2.11 ESD guidelines Software Version SR.505.xx 05/2004 US Edition

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 such modules unless

– the measuring device is earthed (e.g. via PE conductors) or

– you discharge the measuring head just before taking measurements with a potential-free mea-

suring 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 packag-

ing. (Use ESD bags, domestic aluminum foil or paper, for example. 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.