Mitsubishi Electric DLP WD-82CB1, Руководство по обслуживанию

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MODELS: WD-73640 / WD-73740 / WD-73840 / WD-73C11 / WD-73CA1 /
WD-82740 / WD-82840 / WD-82CB1 / WD-92840
Versi
on 3.0
SAFETY PRECAUTIONS
NOTICE:
Observe all cautions and safety related notes located inside the receiver cabinet and on the receiver chassis.
WARNING:
1. Operation of this receiver outside the cabinet or with the cover removed presents a shock hazard from the
receiver's power supplies. Work on the receiver should not be attempted by anyone who is not thoroughly
familiar with the precautions necessary when working on high voltage equipment.
2. When service is required, observe the original lead dress. Where a short-circuit has occurred, replace those
components that indicate evidence of overheating.
SAFETY PRECAUTION
To protect your eyes, do not look directly into the lamp, or light coming directly from the lamp, lens or
mirror.
Leakage current check
Before returning the receiver to the customer, it is recommended that leakage current be measured according to the
following methods.
1. Cold Check
With the alternating current (AC) plug removed from the AC source, place a jumper across the two AC plug
prongs. Connect one lead of an ohm meter to the AC plug and touch the other lead to each exposed metal
part (i.e. antennas, handle bracket, metal cabinet, screw heads, metal overlay, control shafts, etc.), particularly
any exposed metal part that has a return path to the chassis. The resistance of the exposed metal parts hav-
ing a return path to the chassis should be a minimum of 1Meg Ohm. Any resistance below this value indi-
cates an abnormal condition and requires corrective action.
2. Hot Check ...Use the circuit shown below to perform the hot check test.
1. Keep switch S1 open and connect the receiver to the measuring circuit. Immediately after connection,
and with the switching devices of the receiver in their operating positions, measure the leakage current
for both positions of switch S2.
2. Close switch S1, energizing the receiver. Immediately after closing switch S1, and with the switching
devices of the receiver in their operating positions, measure the leakage current for both positions of
switch S2. Repeat the current measurements of items 1 and 2 after the receiver has reached thermal
stabilization. The leakage current must not exceed 0.5 milliampere (mA).
GWG - Green Wire Ground
(Earth Ground)
S2
S1
OPEN
GROUND
SUPPLY CONNECTOR GROUND
RECEIVER
INSULATED TABLE
TOUCH ALL
EXPOSED
METAL PARTS
AC MA
METER
L
N