Minolta magicolor 2300 Series, Service Manual

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12. Disassembly/Assembly Precautions
12-1. Precautions for disassembly and assembly
• Be sure to unplug the power cord from the electrical outlet before attempting to service
the printer.
• To reassemble the unit, reverse the order of disassembly unless otherwise instructed.
• If it is necessary to run the unit with its covers removed, use extreme care not to allow
your fingers or clothing to be caught in drive or rotating parts (such as gears, rollers or
motors).
• Never touch the terminals of electrical components or high-voltage parts (such as the
power unit or the high voltage unit).
• Be careful when working around the fusing unit since it remains hot for a while after the
unit is turned off. Wait until the unit has cooled before starting to disassemble it.
• Be sure that the unit is turned off before plugging in or unplugging connectors. Never
plug in or unplug a connector that is energized. In addition, when plugging in or unplug-
ging connectors, be sure to grasp the connector housing. Never pull on the wires, other-
wise faulty contacts may result.
• Be sure to use fuses of the specified rating.
• To ensure electrical conduction, be sure to attach the ground wire or ground plate. In
addition, be sure to use the indicated screws with toothed washers as instructed.
12-2. Parts that must not be touched
Removal, disassembly or adjustment of the parts listed below must not performed.
• Print head unit (disassembly or adjustment)
• Parts with mounting screws that are painted red.
12-3. Precautions for transporting or storing PWBs
The following precautions must be observed when handling circuit boards.
• During transportation or while in storage, circuit boards must be placed in conductive
cases or on conductive mats and must not be unnecessarily removed. (Do not wrap the
circuit boards in plastic or paper bags.)
• Do not store or place circuit boards in a location where it will be exposed to direct sun-
light.
• When it becomes necessary to remove a circuit board from its conductive case or mat,
do not place where it can easily be subjected to static electricity (such as on carpet or on
plastic or vinyl bags).
12-4. Precautions for replacing PWBs
• Generally, the unit or the assembly should be replaced.
• When unplugging connectors from the circuit board, make sure that the power supply
cord has been unplugged from the electrical outlet.
• When removing a circuit board from its conductive bag or case or when replacing the cir-
cuit board, be sure to hold the board by its edges, making sure not to touch pins of the
ICs or the printed pattern.
12-5. Precautions for inspecting PWBs
• Avoid checking ICs directly with a multimeter; use connectors on the circuit board.
• Never create a closed circuit across IC pins with a metal tool.
• When it is necessary to touch ICs and other electrical components on the circuit board,
be sure to first ground yourself.