Canon CXDI-80C, Руководство по обслуживанию

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4. Repair Guide
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1. Restrictions on disassembly and repair work
The following restrictions are set in place in order to prevent unnecessary trouble from being
encountered in the course of the disassembly and repair work.
• Parts and areas not described in the repair guide must not be disassembled or repaired.
• The discrete parts (such as the electrical boards) described in the parts catalog must not be
disassembled or repaired.
2. Precautions
2.1 Repair and maintenance inspections
In order to ensure safety and give full rein to performance, the repair and maintenance
inspection and other such work must NOT be undertaken by any individuals who have not
undergone the service training.
2.2 Removal of external covers
Before opening the external covers (X-ray interface box, AC/DC box) for the purposes of repair
and maintenance inspection and other such work, the power must be turned off without fail in
order to ensure safety.
The equipment must NOT be touched with wet hands since electric shocks may result.
Before attempting to perform the repair work, the static charged in the bodies of the individuals
undertaking the work must be discharged, and only after this must the work be carried out.
Similarly, if the PCBs and cable connectors are to be touched when replacing the detector cable,
the static in the bodies of the individuals undertaking the work must be discharged, and only
after this must the work be carried out.
2.3 Confirmation after PCB replacement
After replacing a PCB, do not fail to confirm conduction between the exposed copper traces at
PCB screw securing holes and the case by using an electrical tester. Some PCBs have ground
patterns (exposed copper traces) near the screw securing holes, and these are intended to
establish an electrical connection to the case when the screws are in place. Therefore, after
securing the PCB on the case with the screws, make sure to measure the resistance value
between the ground patterns (exposed copper traces) near the screw securing holes and an
unpainted portion of the case (another screw hole in the case, a ground terminal, etc.) to confirm
conduction (resistance value: 0.1
Ω or less).