7. Never defeat any of the B+ voltage interlocks. Do not apply AC power to
the unit (or any of its assemblies) unless all solid-state heat sinks are
correctly installed.
8. Always connect a test instrument's ground lead to the instrument chassis
ground before connecting the positive lead; always remove the instrument's
ground lead list.
Precautions for Electrostatically Sensitive Devices (ESDS)
1. Some semiconductor("solid state")devices are easily damaged by static
electricity.Such components are called Electrostatically Sensitive devices
(ESDs); examples include integrated circuits and some field-effect
transistors.The following techniques will reduce the occurrence of component
damage caused by static electricity.
2. Immediately before handling any semiconductor components or assemblies,
drain the electrostatic charge from your body by, touching a known earth
ground.Alternatively, wear a discharging wrist-strap device. (Be sure to
remove it prior to applying power-this is an electric shock precaution
3. After removing an ESD-equipped assembly,place it on a conductive surface
such as aluminum foil to prevent accumulation of electrostatic charge.
4. Do not use freon-propelled chemicals. These can generate electrical
charges that damage ESDS.
5. Use only a grounded-tip soldering iron when soldering or unsoldering ESDS.
6. Use only an anti-static solder removal device. Many solder removal devices
are not rated as "anti-static"; these can accumulate sufficient electrical
charge to damage ESDS.
7. Do not remove a replacement ESD front its protective package until you are
ready to install it. Most replacement ESDs are packaged with leads that are
electrically shorted together by conductive foam,aluminum foil or other
conductive materials.
8. Immediately before removing the protective material from the leads of a
replacement ESD, touch the protective material to the chassis or circuit
assembly into which the device will be installed.
9. Minimize body motions when unpackaged replacement ESDS. Motion,
such as brushing clothes together, or lifting a foot from a carpeted floor can
generate, enough static electricity to damage an ESD.
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ACEC
HITACHI
