Daewoo KOG-371H0S Printed Circuit Board KOG-376T1S, KOG-396T1S, Wave Form Remedy Remark

PRINTED CIRCUIT BOARD <KOG-376T1S, KOG-396T1S>

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

Terminal Voltage	LOAD	NO LOAD
8 - 9	AC 23V	AC 27.7V
6 - 7	AC 2.27V	AC 2.79V

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.

2.Voltage Check - Key check point

NO	CHECK POINT	REMARK
1	IC1 PIN 6, 10, 11	-5VDC
2	IC1 PIN 22

T : 20ms(50Hz)

3

IC1 PIN 8 OR 9

				T : 250 ns(4MHz)
- Check method
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

NOTE

Each measure point must be measured with GND points.

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