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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 LCD PROJECTOR outside the cabinet or with the cover removed presents a shock hazard from the
LCD 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 LCD PROJECTOR to the customer, it is recommended that leakage current be measured
according to the following methods.
1. Cold Check
With the AC plug removed from the AC source, place a jumper across the two AC plug prongs. Turn the LCD
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 Fig. 1 to perform this test.
(1) With switch S1 open, connect the LCD 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 LCD
PROJECTOR in all of their operating positions.
(2) Switch S1 is then closed, energizing the LCD PROJECTOR. Immediately after closing the switch, measure the
leakage current using both positions of switch S2, and with the switching devices in the LCD PROJECTOR in
all of their operating positions. Current measurements of items ( 1 ) and (2) are to be repeated after the LCD
PROJECTOR has reached thermal stabilization. The leakage current must not be more than 0.5 milliampere.
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 necessary 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
dressing in the high voltage area. Where a short-circuit has occurred, replace those components that indicate
evidence of overheating.
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 500V D.C. Insulation Tester, connect one lead to the jumpered AC plug and touch the other lead
to each exposed metal 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
AC source
V
S1
Grounding Supply Conductor
LCD PROJECTOR
S2
A
GH
(Grounding)
Open
B
AC Milliammeter
Insulating Table
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