|
76
|
KX-F680BX/KX-F2681BX
3-10. POWER SUPPLY SECTION
(1) Key components for troubleshooting
The following components have been known to break frequently :
F101, D101, Q101, IC101, D201
This comes from our experience of experimental test. For example : power supply,
lighting surge voltage test, withstanding voltage test, intentional short circuit test.....etc.
Caution:
If you find a melted fuse in the unit, don't turn the power on without repairing the unit first. (Except the fuse.)
If you do the fuse will melt again. It has not been repaired. The cause exists same where else.
Because of circuit compostion :
If 24V is not output, don't output.
In most cases (our experience) the symptom is that nothing is output.
There is a high possibility in the primary side more than the secondary side.
5V
±
5%
24.5V
±
4%
25
Ω
2W
1200
Ω
1W
5V
±
5%
24.5V
±
4%
AC INPUT
Input
circuit
Rectifier
circuit
Converting
circuit
Q101
24V
output
circuit
DC-DC
converter
circuit
Voltage feed
back circuit
+5V
OUTPUT
+24V
GND
T101
primary
POWER SUPPLY BLOCK DIAGRAM
DUMMY LOAD to check voltage
secondary
Control
circuit
(IC101)
Over
current
circuit
1
2
3
4
5
6
7
8
V
V
GND
24V
5V
CN302
6
5
4
3
2
1
V
V
V
GND
5V
24V
CN301
:Voltage Meter
Summary of Contents for KX-F680BX
Page 1: ......
Page 11: ......
Page 106: ......
Page 107: ......
Page 108: ......
Page 109: ......
Page 110: ......
Page 111: ......
Page 112: ......
Page 113: ......
Page 114: ......
Page 115: ......
Page 116: ......
Page 117: ......
Page 118: ......
Page 119: ......
Page 120: ......
Page 121: ......
Page 122: ......
Page 123: ......
Page 124: ......
Page 125: ......
Page 126: ......
Page 127: ......
Page 128: ......
Page 129: ......
Page 130: ... 165 KX F680BX KX F2681BX EC1 EC2 EC3 EC4 EC5 EC6 EC7 EC9 EC10 EC11 EC12 EC13 EC8 TOOLS ...
Page 131: ......
Page 133: ......
Page 134: ......
Page 135: ......
Page 136: ......