Acer AL718, Руководство по обслуживанию

Страница: 4 / 44

SAFETY PRECAUTIONS
1. CAUTION: 4-6 Voltage measured must not exceed 1.5 vol
No modification of any circuit should be attempted. RMS, from any exposed metallic part to th
Service work should only be performed after you
ground. A leakage current tester may be
are throughly familiar with all of the following safety
used in the above hot check, in which case
checks and servicing guide lines.
any circuit measured must not exceed 1.0
miliamp. In the case of a measurement
2. SAFETY CHECK exceeding the 1.0 miliamp value, a rework i
Care should be taken while servicing this LCD
required to eliminate the chance of a shock
display. Because of the high voltage used in the
hazard.
inverter circuit. These voltage are exposed in such
areas as the associated transfomer circuits.
3. POWER SUPPLY REQUIREMENTS
The external powr converter for this display
utilizes AC and DC cords , AC cord is
detachable , but DC cord is permanently
attached . Any attempt to replace another
adapter could result in serious problem on the
display.
4. LEAKAGE CURRENT HOT CHECK
4-1 Plug the AC cord directly into the AC outlet.
Do not use an isolation transformer during this
check.
4-2 Connect a 1500 ohm , 10 watt resistor ,
paralleled by a 0.15uF capacitor between each
metallic part and a good earth ground.
4-3 Use an AC voltmeter with 1000 ohm / volt or
more sensitivity and measure the AC voltage
across the combination 1500 ohm resistor
and 0.15uF capacitor.
4-4 Move the resistor connection to each exposed
metallic part and measure the voltage.
4-5 Reverse the polarity of the AC plug in the AC
outlet and repeat the above measurement.
To Metal Parts
V
AC VOLTMETER
1500 10W
0.15u
.
Earth Ground
AL718 B-1