XOCECO TA2933, Руководство по обслуживанию

Страница: 3 / 39

1
Attention: This maintenance manual is only intended for the professional maintenance
personnel to take reference with. Before repairing TV set please carefully read
the following points of attention.
Safety Instruction
Before fixing and aligning this set, please read the following “Points of attention for
Safety “, “Points of attention for Safety of Components” and “X-ray Radiation
Protection“.
Points of attention for Safety
1. Because the city power is connected directly to the hot earth of power supply PCB, in order to
avoid electric shock or damage to instruments, an isolate transformer must be applied during the
fixing procedure.
2. Before moving the CRT, graphite layer conductor must be discharged.
3. Before replacing any components, the power plug must be taken out from the power supply
socket.
4. Before replacing large power resistor, 10mm high must be kept between resistor and PCB.
Points of attention for the components safety
There are many electric and mechanical components on the PCB that are related with the
safety features. These features are not easily visible. Replacement parts that have special safety
characteristic are indicated in the Instruction Manual. Electric components with such features will be
labeled with shadow or labeled with in the detail list. When changing these components, please
refer to the detail list in the manual. Components that have different specification from that in the
detail list may not have the same safety features. They may cause electric shock, fire, increase of
X-ray radiation or other damage.
1. Safety instruction
Before fixing or aligning this set, please read the following “ X-ray radiation protection”, “Safety
measures” and “Points of attention for products”.
1.1 X-ray radiation protection
1.1.1 Too high voltage will produce radiation harmful to human health. To avoid such risk, the
high voltage should be regulated within the limited value. For 25”, the normal value of beam
current should be 26.5 kV at 1.3 mA, for 29”, 29kV at1.4 mA and for 29” pure flat TV set,
30kV.
Under any circumstances, the high voltage should not exceed 31kV (25”), 33 kV (29”), 35kV