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5-4 High Voltage Capacitor

5-5 High Voltage Diode

5-6 Main Relay and Power Control Relay

5-7 Adjustment of Primary Switch, Door Sensing Switch and Monitor Switch

5-2

1. Check continuity of the capacitor with the meter set at the highest resistance scale.
2. Once the capacitor is charged, a normal capacitor shows continuity for a short time, and then indicates 9M

Ω.

3. A shorted capacitor will show continuous continuity.
4. An open capacitor will show constant 9M

Ω.

5. Resistance between each terminal and chassis should read infinite.

1. Isolate the diode from the circuit by disconnecting its leads.
2. With the ohm-meter set at the highest resistance scale, measure across the diode terminals. Reverse the

meter leads and read the resistance. A meter with 6V, 9V or higher voltage batteries should be used to
check the front-to back resistance of the diode (otherwise an infinite resistance may be read in both
directions). The resistance of a normal diode will be infinite in one direction and several hundred K

in

the other direction.

1. When mounting Primary switch and Interlock

Monitor switch to Latch Body, consult the
figure.

2. No specific adjustment during installation of

Primary switch and Monitor switch to the latch
body is necessary.

3. When mounting the Latch Body to the oven

assembly, adjust the Latch Body by moving it so
that the oven door will not have any play in it.
Check for play in the door by pulling the door
assembly. Make sure that the latch keys move
smoothly after adjustment is completed.
Completely tighten the screws holding the Latch
Body to  the oven assembly.

4. Reconnect to Monitor switch and check the

continuity of the monitor circuit and all latch
switches again by following the components test
procedures.

5. Confirm that the gap between the switch

housing and the switch actuator is no more than
0.5mm when door is closed.

1. The relays are located on the PCB Ass'y.  Isolate them from the main circuit by disconnecting the leads. 
2. Operate the microwave oven with a water load in the oven. Set the power level set to high.
3. Check continuity between terminals of the relays after the start pad is pressed.

Precaution

For continued protection against radiation hazard, replace parts in accordance with the wiring diagram and be sure to use the
correct part number for the following switches: Primary and secondary interlock switches, and the interlock monitor switch
(replace all together). Then follow the adjustment procedures below. After repair and adjustment, be sure to check the continuity
of all interlock switches and the interlock monitor switch.

Alignment and Adjustments

Door Open

Door Closed

Primary switch

0

Monitor switch (COM-NC)

0

Monitor switch (COM-NO)

0

Door Sensing S/W

0

Primary Interlock Switch

Lever Door(B)

Body Latch

Door Sensing
Switch

Interlock
Secondaryr
Switch

Summary of Contents for KM2901T

Page 1: ...up hot drink min 1min 10sec hr 10min power clock KM2901T 0 1kg 0 1 kg start 1min stop cancel 1 Precaution 2 Specifications 3 Operating Instructions 4 Disassembly and Reassembly 5 Alignment and Adjustments 6 Troubleshooting 7 Exploded Views and Parts List 8 PCB Diagrams 9 Schematic Diagrams KENWOOD ...

Page 2: ... interlock monitor switch 12 If the fuse is blown by the Interlock Monitor Switch Replace all of the following at the same time Primary and secondary switches as well as the Interlock Monitor Switch The correct adjustment of these switches is described elsewhere in this manual Make sure that the fuse has the correct rating for the particular model being repaired 13 Design Alteration Warning Use ex...

Page 3: ...igh voltages this includes the filament voltage of the magnetron High voltage is present during any cook cycle Before touching any components or wiring always unplug the oven and discharge the high voltage capacitor See Figure 1 1 2 The high voltage capacitor remains charged about 30 seconds after disconnection Short the negative terminal of the high voltage capacitor to to the oven chassis Use a ...

Page 4: ...ING FAN MOTOR OUTSIDE DIMENSIONS 489 W x 275 H x 356 D POWER LEVEL KM2901T 10 80W 4 sec 26 sec 20 160W 7 sec 23 sec 30 240W 10 sec 20 sec 40 320W 13 sec 17 sec 50 400W 16 sec 14 sec 60 480W 19 sec 11 sec 70 560W 22 sec 8 sec 80 640W 25 sec 5 sec 90 720W 28 sec 2 sec 100 800W 30 sec 0 sec ON TIME OFF TIME 2 2 Comparison Chart MODEL FEATURE MORE LESS AUTO COOK DISH AUTO DEFROST O TIME COOK O POWER L...

Page 5: ...top cancel 3 Operating Instructions 3 1 Control Panel 3 1 3 2 Features External Views Door Ventilation Holes Light SafetyInterlockHoles OpenDoorPushButton GuideRoller GlassPlate DoorLatches plated meal auto weight defrost soup hot drink min 1min 10sec hr 10min power clock KM2901T 0 1kg 0 1 kg start 1min stop cancel ControlPanel 489mm 357mm 275mm 200mm 356mm plated meal auto weight defrost soup hot...

Page 6: ...arefully 7 Remove screws from the back panel 8 Take out the fan motor 9 Remove the oven lamp by rotating to pull out from hole of air cover NOTE1 When removing the magnetron make sure that its antenna does not hit any adjacent parts or it may be damaged NOTE2 When replacing the magnetron be sure to remount the magnetron gasket in the correct position and make sure the gasket is in good condition 1...

Page 7: ...r C because it is fragile Following the procedure as shown in the figure insert and bend a thin metal plate between Door E and Door A until you hear the tick sound 1 Insertion depth of the thin metal plate should be 0 5mm or less 4 3 4 Removal of Key Door Spring Remove pin hinge from Door E Detach spring from Door E and key door 4 3 2 Removal of Door C 4 3 3 Removal of Door E Disassembly and Reass...

Page 8: ...ing the drive motor be sure to remount it in the correct position 8 Connect all the leads to the drive motor 9 Screw the deive motor cover to the base plate with a screw driver 10 Remount the coupler in the correct position 4 4 Replacement of Fuse 4 5 Replacement of Drive Motor Disassembly and Reassembly Screw Drive Motor Cover Base Plate Drive Motor After replacement of the defective component pa...

Page 9: ...the FPC connector make sure that the holes on the connector are properly engaged with the hooks on the Plastic Fastener 1 Window display should not be disassembled as its mounting tabs will be broken If repair work is difficult replace with Ass y control panel 2 The membrane key board is attached to the escutcheon base with doublefaced adhesive tape Therefore applying hot air such as using of hair...

Page 10: ...agnetron case should read open 1 The low voltage transformer is located on the control circuit board 2 Remove the low voltage transformer from the PCB Ass y and check continuity 3 Normal resistor reading is shown in the table PRECAUTION 1 High voltage is present at the high voltage terminals during any cook cycle 2 It is neither necessary nor advisable to attempt measurement of the high voltage 3 ...

Page 11: ...atch Body by moving it so that the oven door will not have any play in it Check for play in the door by pulling the door assembly Make sure that the latch keys move smoothly after adjustment is completed Completely tighten the screws holding the Latch Body to the oven assembly 4 Reconnect to Monitor switch and check the continuity of the monitor circuit and all latch switches again by following th...

Page 12: ...test should be made if temperature rise is marginal NOTE 2 Output power in watts is computed by multiplying the temperature rise step E by a factor of 91 times the of centigrade temperature The microwave heat distribution can be checked indirectly by measuring the water temperature rise at certain positions in the oven 1 Prepare five beakers made of Pyrex having 100 milliliters capacity each 2 Mea...

Page 13: ...notification after measurement 1 After adjustment and repair of a radiarion preventing device make a repair record for the measured values and keep the data 2 If the radiation leakage is more than 4 mW cm2 after determining that all parts are in good condition functioning properly and the identical parts are replaced as listed in this manual notift that fact to CENTRAL SERVICE CENTER 5 13 2 At lea...

Page 14: ...fective monitor switch NOTE1 4 Shorted HVCapacitor 5 Shorted HVTransformer NOTE2 NOTE 1 All of these switches must be replaced at the same time refer to adjustment instructions Check continuity of power relay contacts and if it has continuity replace power relay also NOTE 2 When HVTransformer is replaced check diode and magnetron also Oven does not accept 1 Key input is not in Sequence Refer to op...

Page 15: ...be heard 1 Loose fan and fan motor Tighten screws of fan motor 2 Loose screws on H V Transformer Tighten screws of H V Transformer 3 Shorted H V Diode Replace H V Diode Turntable motor does not rotate 1 Open or loose wiring of turntable motor Replace turntable motor 2 Defective turntable motor Oven stops operation during cooking 1 Open or loose wiring of primary Adjust door and latch switches inte...

Page 16: ...s and Parts List 7 1 Exploded Views 7 1 M1 M4 M3 M5 M9 M8 M11 M20 M21 M23 M25 M26 M18 M17 M16 M27 M28 M29 M33 M34 M32 D1 M30 M6 M7 M10 M2 M12 M13 M15 M12 M14 M22 M24 M19 M 31 C1 C2 C3 C4 C5 C6 D5 D6 D4 D7 D8 D2 D3 C7 ...

Page 17: ... 40001A LATCH BODY POM F20 02 40GR NTR 1 M 16 DE74 20102B TRAY COOKING GLASS T5 0 PI288 780G M745 1 M 17 DE92 90436A ASSY GUIDE ROLLER D16 5 MW4370W 1 M 18 DE67 60002A COUPLER PPS 5GR BRN M97G45 1 M 19 DE27 10020A COIL MC CHOKE TC 101 1 M 20 2501 001011 C OIL 910nF 2100V BK 54x35x75mm 20mm 1 M 21 DE61 50106A BRACKET HVC SECC T0 8 W31 L125 8 1 M 22 DE91 70063A ASSY HVD V2M6 PI9 0 0 05MT 1 M 23 DE91...

Page 18: ...745G M745 1 Exploded Views and Parts List 7 4 Control Parts List 7 3 Door Parts List Parts No Description Specification Q ty Remarks DE60 10012A SCREW TAP TITE TH 3 M4 L10 SWR10 ZPC2 TOOTH 1 N F EA DE60 10012A SCREW TAP TITE TH 3 M4 L10 SWR10 ZPC2 TOOTH 1 P C EA DE60 10012A SCREW TAP TITE TH 3 M4 L10 SWR10 ZPC2 TOOTH 1 S M EA DE60 10080A SCREW WASHER M5 L12 2S 4 MGT DE60 10080A SCREW WASHER M5 L12...

Page 19: ...8 P C B Diagrams 8 1 P C B Diagrams 8 1 ...

Page 20: ...TP 1 8x3 2m 1 R19 2001 000290 R CARBON 10Kohm 5 1 8W AA TP 1 8x3 2mm 11 R07 R11 R14 R16 R17 R23 R24 2001 000429 R CARBON 1Kohm 5 1 8W AA TP 1 8x3 2mm 6 R04 R05 R06 R12 R15 R22 2001 000446 R CARBON 2 2Kohm 5 1 2W AA TP 3 3x9mm 2 R03R33 2001 000613 R CARBON 3 9Kohm 5 1 8W AA TP 1 8x3 2m 3 R13R18R20 2001 000841 R CARBON 51ohm 5 1 4W AA TP 2 4x6 4mm 7 R26 R27 R28 R29 R30 R3 1R32 2001 000904 R CARBON 6...

Page 21: ...POWER RELAY MAIN RELAY F FA MAGNETRON NO COM NO NC BLU YEL BRN BRN BRN BLK BLU BLK COM 0V LAMP 230V40W L V TRANS PRIMARY LATCH SWITCH NO COM ORG ORG MONITOR SWITCH L FM H V T H V D H V C H V FUSE 1mH BRN BROWN BLU BLUE ORG ORANGE RED RED WHT WHITE BLK BLACK YEL YELLOW GRN GREEN Y G YELLOW GREEN SYMBOL COLOR NOTE MAIN FUSE DM 1 INPUT 230V 2 DOOR OPEN 3 LAMP ON 4 P C B PATTERN 5 P C B IN OUT POINT A...

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