Daewoo KOG-374R0S Microwave Oven User Manual


 
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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 (point 4).
2. Secondary side voltage of the low voltage trasformer changes in proportion to fluctuation of power source
voltage.
3. The allowable tolerance of the secondary voltage is within 5% of nominal voltage.
NOTE
Each measure point must be measured with GND points.
PRINTED CIRCUIT BOARD <KOG-376T1S, KOG-396T1S>
Terminal Voltage
8 - 9
6 - 7
LOAD
AC 23V
AC 2.27V
NO LOAD
AC 27.7V
AC 2.79V
NO CHECK POINT REMARK
1 IC1 PIN 6, 10, 11 -5VDC
2 IC1 PIN 22
3 IC1 PIN 8 OR 9
T : 20ms(50Hz)
T : 250 ns(4MHz)
NO MEASURE POINT WAVE FORM REMEDY REMARK
1 MP1 DC -5V±0.25V Replace VL1, EC1 NO LOAD
2 MP2 DC -24V±2.0V Replace EC3, D8-11 NO LOAD