2.2.
Touch-Current Check
2 Safety Precautions
2.1.
General Guidelines
1. When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or
damaged by the short circuit.
2. After servicing, see to it that all the protective devices such as insulation barriers, insulation papers shields are properly
installed.
3. After servicing, make the following leakage current checks to prevent the customer from being exposed to shock hazards.
1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.
2. Connect a measuring network for touch currents between each exposed metallic part on the set and a good earth ground such
as a water pipe, as shown in Figure 1.
3. Use Leakage Current Tester (Simpson 228 or equivalent) to measure the potential across the measuring network.
4. Check each exposed metallic part, and measure the voltage at each point.
5. Reserve the AC plug in the AC outlet and repeat each of the above measure.
6. The potential at any point (TOUGH CURRENT) expressed as voltage U
1
and U
2
, does not exceed the following values:
For a. c.: U
1
= 35 V (peak) and U
2
= 0.35 V (peak);
For d. c.: U
1
= 1.0 V,
Note:
The limit value of U
2
= 0.35 V (peak) for a. c. and U
1
= 1.0 V for d. c. correspond to the values 0.7 mA (peak) a. c. and 2.0
mA d. c.
The limit value U
1
= 35 V (peak) for a. c. correspond to the value 70 mA (peak) a. c. for frequencies greater than 100 kHz.
7. In case a measurement is out of the limits specified, there is a possibility of a shock hazard, and the equipment should be
repaired and rechecked before it is returned to the customer.
Figure 1
6
TH-37PE30B / TH-42PE30B
Содержание TH-42PE30B
Страница 5: ...1 Applicable signals 5 TH 37PE30B TH 42PE30B ...
Страница 15: ...7 Location of Lead Wiring 7 1 Lead of Wiring 1 15 TH 37PE30B TH 42PE30B ...
Страница 16: ...7 2 Lead of wiring 2 16 TH 37PE30B TH 42PE30B ...
Страница 17: ...7 3 Lead of wiring 3 17 TH 37PE30B TH 42PE30B ...
Страница 18: ...7 4 Lead of wiring 4 7 5 Lead of wiring 5 18 TH 37PE30B TH 42PE30B ...
Страница 19: ...7 6 Lead of wiring 7 19 TH 37PE30B TH 42PE30B ...
Страница 25: ...25 TH 37PE30B TH 42PE30B ...
Страница 26: ...9 3 Option Description 26 TH 37PE30B TH 42PE30B ...
Страница 27: ...27 TH 37PE30B TH 42PE30B ...
Страница 30: ...10 4 IIC mode structure following items value is sample data 30 TH 37PE30B TH 42PE30B ...
Страница 34: ...12 Alignment 12 1 Pedestal setting 34 TH 37PE30B TH 42PE30B ...
Страница 35: ...12 2 PAL panel white balance 35 TH 37PE30B TH 42PE30B ...
Страница 36: ...12 3 PC panel white balance 36 TH 37PE30B TH 42PE30B ...
Страница 37: ...12 4 Sub brightness setting 12 5 ABL Level 37 TH 37PE30B TH 42PE30B ...
Страница 71: ...15 Block and Schematic Diagrams 15 1 Schematic Diagram Notes TH 37PE30B TH 42PE30B 71 ...
Страница 137: ...16 Parts Location 137 TH 37PE30B TH 42PE30B ...
Страница 138: ...17 Packing Exploded Views 138 TH 37PE30B TH 42PE30B ...
Страница 139: ...139 TH 37PE30B TH 42PE30B ...