DAEWOO ELECTRONICS DV-F882DY-C Service Manual page 3

• Safety Check after Servicing
Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires
have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order
to verify compliance with safety standards.
1. Insulation resistance test
Confirm the specified insulation resistance or greater between power cord plug prongs and externally exposed parts of
the set (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone
jacks, etc.). See table below.
2. Dielectric strength test
Confirm specified dielectric strength or greater between power cord plug prongs and exposed accessible parts of the
set (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks,
etc.) See table below.
3. Clearance distance
When replacing primary circuit components, confirm
specified clearance distance (d), (d') between soldered
terminals, and between terminals and surrounding
metalic parts. See table below.
Table 1: Rating for selected areas
AC Line Voltage
100V
110 to 130V
* 110 to 130 V
200 to 240 V
* Class II model only.
Note: This table is unofficial and for reference only. Be sure to confirm the precise values for your particular country and
locality.
4. Leakage current test
Confirm specified or lower leakage current between B (earth ground, power cord plug prongs) and externally exposed
accessible parts (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks,
earphone jacks, etc.)
Measuring Method: (Power ON)
Insert load Z between B (earth ground, power cord plug
prongs) and exposed accesible parts. Use and AC
voltmeter to measure across both terminals of load Z.
See figure 2 and following table.
Table 2: Leakage current ratings for selected areas
AC Line Voltage
100V
110 to 130 V
110 to 130 V
200 to 240 V
Note: This table is unofficial and for reference only. Be sure to confirm the precise values for your particular country and
locality.
Insulation
Region
Resistance
≥ 1 MΩ/500 V DC
Japan
USA &
– – –
Canada
≥ 4 MΩ/500 V DC
Europe
Australia
Load Z
Region
Japan
1k
1.5kµF
USA &
2k
Europe
Australia
50k
d
d'
Chassis
Fig. 1
Dielectric
Strength
1kV AC 1 minute
900V AC 1 minute
3 kV AC 1 minute
Exposed
accessible
part
Z
Earth Ground
B power cord plug prongs
Fig. 2
Leakage Current (i)
¡ ≤ 1m A rms
¡ ≤ 0.5 m A rms
1.5k
¡ ≤ 0.7 m A peak
¡ ≤ 2 m A dc
¡ ≤ 0.7 m A peak
¡ ≤ 2 m A dc
Primary circuit termimals
a
Clearance
Distance (d), (d')
≥ 3 mm
≥ 3.2mm
≥ 6 mm (d)
≥ 8 mm (d')
(a: Power cord)
AC Voltmter
(high impedance)
Earth Ground
(B) to:
Exposed accessible
parts
Exposed accessible
parts
Antenna earth
terminals
Other terminals