26
PRINTED CIRCUIT BOARD
1. CIRCUIT CHECK PROCEDURE
1. Low Voltage Transformer check
• The low voltage transformer is located on the P.C.B.
• Measuring condition: input voltage : 120V / Frequency : 60Hz
2. Voltage check
• Key check point
• Check method
NO
CHECK POINT
REMARK
1
IC 1 PIN 5
5 VDC
2
IC 1 PIN 8
3
IC 1 PIN 35 OR PIN 36
NOTE :
Each measure point must be measured with GND points.
NOTE :
1. Refer to Circuit Diagram.
2. Secondary side voltage of the low voltage transformer changes in proportion to fluctuation of power source voltage.
3. The allowable tolerance of the secondary voltage is within ± 5% of nominal voltage.
Terminal Voltage
(4,5)-6-7
LOAD
AC 12.6 V
NO LOAD
AC 14.7 V
NO
MEASURE POINT
WAVE FORM
REMEDY
REMARK
1
MP1
DC 5V ±0.25V
Replace VL1, EC1
NO LOAD
2
MP2
DC 15V ±2.0V
Replace EC2, D11, D13, D14
NO LOAD
T
T:16.67ms(60Hz)
5V
0V
T
T:250ns(4MHz)
5V
0V
Summary of Contents for KOR-164H0W
Page 5: ...5 EXTERNAL VIEW 1 OUTER DIMENSION ...
Page 25: ...25 WIRING DIAGRAM ...
Page 27: ...27 Measure Point MP1 GND MP2 ...
Page 29: ...29 2 PCB CIRCUIT DIAGRAM ...