ViewSonic E70F Service Manual - Page 5

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5-4 Move the resistor connection to each exposed metallic part and measure the voltage. 5-5 Reverse the polarity of the AC plug in the AC outlet and repeat the above measurement. 5-6 Voltage measured must not exceed 7.5 volt RMS, from any exposed metallic part to ground A leakage current tester may be used in the above hot check, in which case any current measured must not exceed 5.0 milliamp. In the case of a measurement exceeding the 5.0 milliamp value, a rework is required to eliminate the chance of shock hazard. NoteΚ High voltage is present when this CRT display is operating. Always discharge the anode of the picture tube to the display chassis to prevent shock hazard. AC VOLTMETER TO INSTRUMENT'S EXPOSED METAL PARTS 0.15ӴF 1500 Ө 10W (EARTH GROUND) 6. IMPLOSION PROTECTION Fig. 1 Picture tubes are equipped with an integral implosion protection system, but care should be taken to avoid damage and scratching during installation. Use only Panasonic replacement picture tubes. 7. X-RADIATION WARNINGΚThe only potential source of X-Radiation is the picture tube. However when the high voltage circuit is operating properly there is no possibility of X-Radiation problem. The basic precaution which must be exercised is to keep the high voltage at the following factory-recommended level. NoteΚ It is important to use an accurate periodically calibrated high voltage meter. 7-1 The procedure for adjusting high voltage is shown on page 27. 7-2 If can not be adjust 25.0 KV at immediate service is required to prevent the possibility of premature component failure. 7-3 To prevent X-Radiation possibility it is essential to use the specified picture tube. IMPORTANT SAFETY NOTICE There are special components used in this CRT displays which are important for safety. These parts are identified ! by the international symbol on the schematic diagram and on the replacement parts list. It is essential that these critical parts should be replaced with manufacture's specified parts to prevent X-RADIATION, shock, fire, or other hazards. Do not modify the original design or this will void the original parts and labor guarantee. ViewSonic Corporation Confidential - Do Not Copy E70f+SB-3 2

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5-4
Move the resistor connection to each exposed metallic part and measure the voltage.
5-5
Reverse the polarity of the AC plug in the AC outlet and repeat the above measurement.
5-6
Voltage measured must not exceed 7.5 volt RMS, from any exposed metallic part to ground A leakage current
tester may be used in the above hot check, in which case any current measured must not exceed 5.0 milliamp. In
the case of a measurement exceeding the 5.0 milliamp value, a rework is required to eliminate the chance of
shock hazard.
Note
High voltage is present when this CRT display is operating. Always discharge the anode of the picture
tube to the display chassis to prevent shock hazard.
AC VOLTMETER
TO
INSTRUMENT'S
EXPOSED
METAL PARTS
1500
10W
0.15
F
Fig. 1
(EARTH
GROUND)
6.
IMPLOSION PROTECTION
Picture tubes are equipped with an integral implosion protection system, but care should be taken to avoid damage and
scratching during installation. Use only Panasonic replacement picture tubes.
7.
X-RADIATION
WARNING
The only potential source of X-Radiation is the picture tube. However when the high voltage circuit is
operating properly there is no possibility of X-Radiation problem. The basic precaution which must be exercised is to
keep the high voltage at the following factory-recommended level.
Note
It is important to use an accurate periodically calibrated high voltage meter.
7-1
The procedure for adjusting high voltage is shown on page 27.
7-2
If can not be adjust 25.0 KV at immediate service is required to prevent the possibility of premature
component failure.
7-3
To prevent X-Radiation possibility it is essential to use the specified picture tube.
IMPORTANT SAFETY NOTICE
There are special components used in this CRT displays
which are important for safety. These parts are identified
by the international symbol
!
on
the
schematic
diagram and on the replacement parts list. It is essential
that
these
critical
parts
should
be
replaced
with
manufacture’s specified parts to prevent X-RADIATION,
shock, fire, or other hazards. Do not modify the original
design or this will void the original parts and labor
guarantee.
2
ViewSonic Corporation
Co
nfidential
- Do Not Copy
70f+SB-3
E