Panasonic OmniVision PV-M1326 Service Manual Download

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COLD
WATER PIPE
(EARTH GROUND)

1500

Ω

. 10W

0.15µF

AC VOLTMETER

Hot-Check Circuit

TO
APPLIANCES
EXPOSED
METAL PARTS

SAFETY PRECAUTIONS

GENERAL GUIDELINES

1. It is advisable to insert an isolation transformer in the AC supply before servicing.
2. When servicing, observe the original lead dress, especially the lead dress in the high voltage circuits. If a short circuit is found,

replace all parts which have been overheated or damaged by the short circuit.

3. After servicing, see to it that all the protective devices such as insulation barriers, insulation papers, shield, and isolation R-C

combinations are properly installed.

4. Before turning the receiver on, measure the resistance between B+ line and chassis ground. Connect (-) side of an ohmmeter

to the B+ lines, and (+) side to chassis ground. Each line should have more resistance than specified, as follows :

B+ Line

Minimum Resistance

130V

1K ohm

(Hot chassis ground)

27V

180 ohms

(Cold chassis ground)

17V

110 ohms

(Cold chassis ground)

5. When the TV set is not used for a long period of time, unplug the power cord from the AC outlet.
6. Potentials, as high as

25.0KV : Model A,B,C,D,E,F,G

30.0KV : Model H,I,J,K

32.0KV : Model L

(see chart above) are

present when this TV set is in operation. Operation of the TV set without the rear cover involves the danger of a shock hazard from
the TV set power supply. Servicing should not be attempted by anyone who is not thoroughly familiar with the precautions
necessary when working on high voltage equipment. Always discharge the anode of the picture tube to the CRT ground of receiver
before handling the tube.

7. After servicing make the following leakage current checks to prevent the customer from being exposed to shock hazards.

LEAKAGE CURRENT COLD CHECK

1. Unplug the AC cord and connect a jumper between the two prongs on the plug.
2. For physically operated power switches, turn power on. Otherwise skip step 2.
3. Measure the resistance value, with an ohmmeter, between the jumpered AC plug and each exposed metallic cabinet part on the

receiver, such as screwheads, connectors, etc. When the exposed metallic part has a return path to the chassis, the reading should
be between 1 M ohm and 12 M ohms. When the exposed metal does not have a return path to the chassis, the reading must
be

∞

MODEL

MARK

MODEL

MARK

PV-M1326

PV-M1356W

PV-M1326W

PV-M2036

VV1306

VV2006

VV1306B

VV2016W

VV1316W

PV-M2046

PV-M1346

VV2706

COMPARISON CHART OF MODELS AND MARKS

LEAKAGE CURRENT HOT CHECK (See Figure 1)

1. Plug the AC cord directly into the AC outlet.

Do not use a isolation transformer for this check.

2. Connect a 1.5K ohms, 10 watts resistor, in parallel with a 0.15

capacitor, 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 an AC voltmeter, with 1000 ohms/volt or more sensitivity,

to measure the potential across the resistor.

4. Check each exposed metallic part, and measure the voltage at

each point.

5. Reverse the AC plug in the AC outlet and repeat each of the

above measurements.

6. The potential at any point should not exceed 0.75 volt RMS.

A leakage current tester (Simpson Model 229 equivalent) may
be used to make the hot checks, leakage current must not
exceed 1/2 milliamp. In case a measurement is outside of the
limits specified, there is a possibility of shock hazard, and the
receiver should be repaired and rechecked before it is returned
to the customer.

Figure 1