JVC TK-C400E, Service Manual

Page: 4 / 52

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 compli-
ance 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 1 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 1 below.
3. Clearance distance
When replacing primary circuit components, confirm specified clearance distance (d), (d’) be-
tween soldered terminals, and between terminals and surrounding metallic parts. See table 1
below.
4. Leakage current test
Confirm specified or lower leakage current between 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 earth ground/power cord plug prongs and externally exposed accessi-
ble parts. Use an AC voltmeter to measure across both terminals of load Z. See figure 9 and
following table 2.
5. Grounding (Class
1
model only)
Confirm specified or lower grounding impedance between earth pin in AC inlet and externally exposed accessible parts (Video in,
Video out, Audio in, Audio out or Fixing screw etc.).
Measuring Method:
Connect milli ohm meter between earth pin in AC inlet and exposed accessible parts. See figure 10 and grounding specifications.
d '
d
Chassis
Power cord,
primary wire
Region
USA & Canada
Europe & Australia
Grounding Impedance (Z)
Z 0.1 ohm
Z 0.5 ohm
≤
≤
AC inlet
Earth pin
Exposed accessible part
Milli ohm meter
Grounding Specifications
Fig. 10
a b
c
V
A
Externally
exposed
accessible part
Z
Fig. 9
Fig. 8
Clearance Distance (d), (d')
d, d' 3 mm
d, d' 4 mm
d, d' 3.2 mm –
Dielectric Strength
AC 1 kV 1 minute
AC 1.5 kV 1 miute
AC 900 V 1 minute
AC Line Voltage
100 V
100 to 240 V
110 to 130 V
110 to 130 V
200 to 240 V
Japan R 1 M
Ω
/500 V DC
USA & Canada
Europe & Australia R 10 M
Ω
/500 V DC
Region Insulation Resistance (R)
≤
≤
≤
≤
≤
≤
≤
≤
AC 3 kV 1 minute
(Class 2 )
AC 1.5 kV 1 minute
(Class
1
)
d 4 mm
d' 8 mm (Power cord)
d' 6 mm (Primary wire)
Table 1 Specifications for each region
a, b, c Leakage Current (i) AC Line Voltage
100 V
110 to 130 V
110 to 130 V
220 to 240 V
Japan
USA & Canada
i 1 mA rms Exposed accessible parts
Exposed accessible parts
Antenna earth terminals
Other terminals
i 0.5 mA rms
i 0.7 mA peak
i 2 mA dc
i 0.7 mA peak
i 2 mA dc
Europe & Australia
Region Load Z
≤
≤
≤
≤
≤
≤
1 k
Ω
2 k
Ω
1.5 k
Ω
0.15
µ
F
50 k
Ω
Table 2 Leakage current specifications for each region
Note: These tables are unofficial and for reference only. Be sure to confirm the precise values for your particular country and locality.
2