Canon LV-7545U, Service Manual

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Part 2: Repair Information
2-1
1. SAFETY INSTRUCTIONS
The following precautions must be observed during servicing and inspection.
Observe all safety precautions.
Comply with all caution and safety-related notes provided on the cabinet back, cabinet
bottom, inside the cabinet, on the chassis or components, as well as the precautions
shown in the instruction manual during servicing.
Avoid electric shock.
Since an AC voltage is applied to the chassis for the set, touching the chassis during
power-on may cause electric shock. When service is performed during power on, use an
insulation transformer, wear protective gloves, and remove the plug during parts
replacement. As there are high-voltage areas inside the projector, handle it with care
when the power is on.
Use specified parts.
The parts of the set have safety properties, such as inflammability and voltage
withstand. Therefore, use replacement parts with the same characteristics as the
original ones. The critical components for safety are indicated by mark in the
schematic diagram and parts list must be replaced by the recommended parts.
Reinstall parts and wires in their original positions.
Insulating materials, such as tubes and tape, are used and some components are
installed over a PC board for safety. Reinstall internal wires with clamps so that they do
not touch any heat-generating or high-voltage parts.
Safety check after service
Verify that service locations are not deteriorated and all removed screws, parts and
wires are installed in their original positions. In addition, perform the following test to
ensure safety.
Insulation resistance test method
Remove the plug from the electric outlet and press the power switch. Using a 500V
insulation resistance tester (or a multimeter if any insulation resistance tester is not
available), check that the insulation resistance between each terminal of the plug and
external exposed connector (external speaker connector, remote control connector, AV
input/output connector, etc.) is 1Mohm or higher. If not, the set must be inspected and
repaired.
Components indicated by mark in the parts list and the schematic diagram designate components in
which safety can be of special significance. It is, therefore, particularly recommended that the
replacement of there parts be made by exactly the same parts. Using unspecified parts may worsen
failure or cause fire or electric shock.
Eye damage may result from directly viewing the light produced by the lamp used in this equipment.
Always turn off the lamp before opening the cover.
Never turn the power on without the lamp to avoid electric shock or damage of the devices since the
stabilizer generates high voltages (15kV - 25kV) at its starts.
Since the lamp is very high temperature during units operation replacement of the lamp should be done at
least 45 minutes after the power has been turned off, to allow the lamp cool-off.
Precautions for servicing