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TRADEMARK, REGISTERED TRADEMARK
DLPTM (Digital Light Processing) and DMD (Digital Micromirror Device) are trademarks of Texas Instruments Incorporated.
Other brand or product names are trademarks or registered trademarks of their respective holders.
PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in the projector have special safety related characteristics. These characteristics are often
not evident from visual inspection nor can the protection afforded by them necessarily be obtained by using replacement com-
ponents rated for higher voltage, etc. Replacement parts which have these special safety characteristics are identified in this
service manual. Electrical components having such features are identified by shading on the schematic diagram and the parts
list of this service manual and by the supplementary sheet for this chassis to be issued subsequently.
-1-
SAFETY PRECAUTIONS
North america
NOTICE: Observe all cautions and safety related notes located inside the cabinet and on the chassis.
Warning
1. Operation of this projector outside the cabinet or with the cover removed presents a shock hazard from the projector power
supplies.
2. When a short-circuit has occurred, replace those components that indicate evidence of overheating.
3. Grounding circuit continuity is vital for safe operation of equipment. Do not remove ground connection while the power cord
is still connected to the supply. Disconnect supply before servicing.
Leakage current check
Before returning the projector to the customer, it is recommended that leakage current be measured according to the follow-
ing methods.
1. Cold check
With the AC plug removed from the AC 100 to 240 V, place a jumper across the two AC plug prongs. Turn the projector AC
switch on. Using an ohm-meter, connect one lead to the AC plug and touch the other lead to each exposed metal part (metal
cabinet, screwheads, metal overlays, etc.), particularly any exposed metal part having a return path to the chassis. Exposed
metal parts having a return path to the chassis should have a minimum resistance reading of 1 megohm. Any resistance
below this value indicates an abnormality which requires corrective action. Exposed metal parts not having a return path to
the chassis will indicate an open circuit.
2. Hot check
Use the circuit in figure to perform this test.
(1) With switch S1 open, connect the projector to the measuring circuit. Immediately after connection, measure the leakage
current using both positions of switch S2, and with the switching devices in the projector in all of their operating positions.
(2) Switch S1 is then closed, energizing the projector. Immediately after closing the switch, measure the leakage current us-
ing both positions of switch S2, and with the switching devices in the projector in all of their operating positions. Current
measurements of items (1) and (2) are to be repeated after the projector has reached thermal stabilization. The leakage
current must not be more than 0.5 milliampere.
Projector AC milliammeter
S2
A
AC 100 to 240 V V
GH
S1 (grounding)
open
Insulating table
Grounding supply conductor
B
Figure
Europe, other than USA
NOTICE: Observe all cautions and safety related notes located inside the cabinet and on the chassis.
Warning
1. An isolation transformer should be used between the projector and the AC supply point before any test/service is performed
on a LIVE chassis projector.
2. Operation of this projector outside the cabinet or with the cover removed, involves a shock hazard from the projector power
supplies. Work on the projector should not be attempted by anyone who is not thoroughly familiar with precautions neces-
sary when working on high voltage equipment.
3. When service is required, observe the original lead dressing. Extra precaution should be given to assure correct lead dress-
ing in the high voltage area. Where a short-circuit has occurred, replace those components that indicate evidence of over-
heating.
Leakage current cold check
Before returning the projector to the customer, it is recommended that leakage current be measured according to the following
methods.
With the AC plug removed from the AC source, place a jumper across the two AC plug prongs. Turn the projector AC switch on.
Using an 500 V D.C. Insulation Tester, connect one lead to the jumpered AC plug and touch the other lead to each exposed met-
al part (screwheads, etc.), particularly any exposed metal part having a return path to the chassis. Exposed metal parts having a
return path to the chassis should have a minimum resistance reading of 4 megohm. Any resistance below this value indicates an
abnormality which requires corrective action.
-2-
PRECAUTIONS FOR RESOLDERING
Lead-free solder is handled in a different way from eutectic solder. See below for details.
How to distinguish circuit boards using lead-free solder from those using
eutectic solder
Circuit boards using lead-free solder
A mark of Solder, Joints, PCA or LFS (for limited marking space) is printed near the board assembly number on
the component side.
Circuit boards using eutectic solder
Circuit boards using eutectic solder are divided into two groups.
- Boards having no mark of Solder, Joints, PCA or LFS (for limited marking space) near the board assembly
number.
- Boards having a mark of Solder, Joints, PCA or LFS (for limited marking space) that is painted out by a felt-
pen near the board assembly number.
* Only when there is a limited marking space on the board, Solder may be indicated as S, Joints as J, and
PCA as P.
* Circuit boards using lead-free solder and those using eutectic solder may be used together in the same product.
Instructions for resoldering
- For circuit boards using lead-free solder, use lead-free solder.
- For circuit boards using eutectic solder, use eutectic solder.
- Separate the soldering iron for lead-free solder from that for eutectic solder completely for use.
(It is prohibited to use a same soldering iron for lead-free solder and eutectic solder.)
- For lead-free solder, it is advisable to use a soldering iron of at least 40 W because lead-free solder has a melting point ap-
prox. 35