Keithley 2750, Service Manual

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Model 2750 Multimeter/Switch System Service Manual Disassembly 5-3
Disassembl
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Static sensitive devices
CMOS devices operate at very high impedance levels. Therefore, any static that builds up
on you or your clothing may be sufficient to destroy these devices if they are not handled
properly. Use the following precautions to avoid damaging them:
CAUTION Many CMOS devices are installed in the Model 2750. Handle all semicon-
ductor devices as being static sensitive.
• Transport and handle ICs only in containers specially designed to prevent static
build-up. Typically, you will receive these parts in anti-static containers made of
plastic or foam. Keep these devices in their original containers until ready for
installation.
• Remove the devices from their protective containers only at a properly grounded
work station. Also, ground yourself with a suitable wrist strap.
• Handle the devices only by the body; do not touch the pins.
• Ground any printed circuit board into which a semiconductor device is to be
inserted to the bench or table.
• Use only anti-static type desoldering tools.
• Use only grounded-tip soldering irons.
• Once the device is installed in the PC board, it is normally adequately protected
and you can handle the boards normally.
Assembly drawings
Use the following assembly drawings to assist you as you disassemble and reassemble the
Model 2750. Refer to these drawings for information about the Keithley part numbers of
most mechanical parts in the unit. The drawings are located at the end of this section of the
manual.
• Front Panel Assembly — 2750-040.
• Card Cage/Power Module Assembly — 2750-050.
• Power Module/Transformer/Chassis Assembly — 2750-051.
• Front Panel/Card Cage/Chassis Assembly — 2750-052.
• Chassis Assembly — 2750-053, 2750-054.
• Final Inspection — 2750-080.