Daewoo KOR664BWTAE013AB00 - Printed Circuit Board; Circuit Check Procedure

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PRINTED CIRCUIT BOARD
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.
2. Voltage Check
- Key check point
- Check method
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
NOTE
Each measure point must be measured with GND points.
Terminal Voltage LOAD NO LOAD
(4,5)-6 or (7,8)-6 DC 11V AC 30V
NO MEASURE POINT WAVE FORM REMEDY REMARK
1 MP1 DC 5V±0.25V Replace Q8, R28, ZD3, C2, EC1 NO LOAD
2 MP2 DC 11V±3.0V Replace EC3, D11, D12, D13 NO LOAD
NO CHECK POINT REMARK
1 IC1 PIN 5 5VDC
2 IC1 PIN 8
3
IC 1 PIN 19 OR PIN 20
T : 16.67ms(60Hz)
5V
0V
T : 250 ns(4MHz)
5V
0V