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 |
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6 - 7 | AC 2.27V | AC 2.79V |
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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 |
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1 | IC1 PIN 6, 10, 11 | |
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2 | IC1 PIN 22 |
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T : 20ms(50Hz)
3
IC1 PIN 8 OR 9
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| T : 250 ns(4MHz) | |
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- Check method |
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NO | MEASURE POINT | WAVE FORM |
| REMEDY |
| REMARK | |||||
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1 | MP1 | DC |
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| Replace VL1, EC1 |
| NO LOAD | ||||
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2 | MP2 | DC |
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| Replace EC3, |
| NO LOAD | ||||
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NOTE
Each measure point must be measured with GND points.
60
