Daewoo KQG-8A6K5S, Руководство по обслуживанию, Страница: 27 / 37

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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: 230V / Frequency: 50Hz
2. Voltage Check
- Key check point
- Check method
NOTE
1. Refer to Circuit Diagram.
2. Secondary side voltage of the low voltage transformer changes in proportion to fluctuation of power source volt-
age.
3. The allowable tolerance of the secondary voltage is within ± 5% of nominal voltage.
NOTE
Each measure point must be measured with GND points.
Terminal Voltage
5-6-7
LOAD
AC 12.6 V
NO LOAD
AC 14.7 V
NO CHECK POINT REMARK
1 IC1 PIN 5 5VDC
2 IC1 PIN 8
3 IC1 PIN 35 OR PIN 36
NO MEASURE POINT WAVE FORM REMEDY REMARK
1 MP1 DC 5V±0.25V Replace VL1, EC1 NO LOAD
2 MP2 DC 12V±2.0V Replace EC2, D12, D13, D14 NO LOAD
T
T : 16.67ms(60Hz)
5V
0V
T
T : 250 ns(4MHz)
5V
0V