Siemens PC 870 manual Handling ESD assemblies

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Appendix B: ESD Guidelines

Handling ESD assemblies

A general rule is that assemblies should be touched only when this cannot be avoi- ded in the course of the work that has to performed on them. Under no circumstan- ces should you touch device pins or circuitry when handling printed-circuit boards.

You should touch devices only if

￿you are grounded by permanently wearing an ESD wrist strap or

￿you are wearing ESD shoes or ESD shoe-grounding protection straps in con- junction with an ESD floor.

Before you touch an electronic assembly, your body must be discharged. The simplest way of doing this is to touch a conductive, grounded object immediately beforehand (e.g. bare metal parts of a cabinet, water pipe, etc.).

Assemblies should not be brought into contact with charge-susceptible and highly insulating materials such as plastic films, insulating table tops and items of clothing etc. containing synthetic fibers.

Assemblies should be deposited only on conductive surfaces (tables with an ESD coating, conductive ESD cellular material, ESD bags, ESD shipping containers).

Do not place assemblies near visual display units, monitors or television sets (minimum distance to screen > 10 cm).

Measuring and modifying ESD assemblies

Perform measurements on ESD assemblies only if

￿the measuring instrument is grounded (e.g. by means of a protective conductor) or

￿the measuring head has been briefly discharged before measurements are made with a potential-free measuring instrument (e.g. by touching a bare metal control cabinet).

When soldering, use only grounded soldering irons.

Shipping ESD assemblies

Always store and ship assemblies and devices in conductive packing, e.g. metallized plastic boxes and tin cans.

If packing is not conductive, assemblies must be conductively wrapped before they are packed. You can use, for example, conductive foam rubber, ESD bags, dome- stic aluminum foil or paper (never use plastic bags or foils).

With assemblies containing fitted batteries, make sure that the conductive packing does not come into contact with or short-circuit battery connectors. If necessary, cover the connectors beforehand with insulating tape or insulating material.

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SIMATIC Panel PC 670 / 870 Operating Unit, Equipment Manual

Edition 07/01

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Contents Equipment Manual Panel PC 670 / 870 Operating UnitAppendices Safety information Qualified personnel Correct usage Trademarks ImpressumPage Purpose of the manual PrefaceTarget group Documentation Edition CommentsCustomer Support, Technical Support Nuremberg Johnson City Singapore Simatic HotlineTechnical Support Simatic Customer Support Online ServicesAuthorization Technical Support Europe / Africa NurembergTable of Contents Index-1 Appendix B ESD Guidelines IndexProduct Overview UsagePanel PC 670 Computing and operating units Keyboard versionsTouchscreen versions Panel PC 870 Computing and operating units Shows an example of the complete deviceTouchscreen version Page Description of Device Available in combination with 10º 12º 15º TouchOperating units with key-based front panels Status indicationsSoft keys KeyboardFunction keys Control keysAlpha keys Integrated mouse ConnectingExternal keyboards Operating units with touchscreen front panels Status indicatorsOperation Front-side USB interface InterfacesRear-side interfaces Interface assignment Signal typeFront-side USB interface T2 ± Device dimensionsDimensions of Panel PC ± 2 ÜComputing unit Swung away by Mounting cut-out MountingPanel PC Mounting Installation Clamp fixing Installation withScrew fixing L2 +1 L5 ±A1 ±1 L3 ± L1 +1 A2 ±1Operating unit Computing unit Accessories MaintenanceSpare parts and accessories Spare partsDetaching the operating unit from the computing unit Removing the computing unit completely Rear side of operating panel with positions of interfacesRemoving Proceed as follows Computing unit Cable K1 Slits for mounting rails Slits for vertical soft key labeling strips Appendix a Technical Data Technical data of operating unitAppendix a Technical Data Keyboard table operating units with key-based front panels Key number Code Key label/nameAppendix a Technical Data Blank Explanation of values in the table Appendix B ESD Guidelines What does ESD mean?Handling ESD assemblies Index Index