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H. V. Diode

Short

H. V. Capacitor

1-2 Special Servicing Precautions (Continued)

17. When checking the continuity of the witches

or transformer, always make sure that the
power is OFF, and one of the lead wires is
disconnected.

18. Components that are critical for safety are

indicated in the circuit diagram by
shading,

or

.

19. Use replacement components that have the

same ratings, especially for flame resistance
and dielectric strength specifications. A
replacement part that does not have the
same safety characteristics as the original
might create shock, fire or other hazards.

NOTE : Connect the oven to a 20A. When connecting the oven to a 15A,

make sure that circuit breaker can operate.

1-3 Special High Voltage Precautions

1. High Voltage Warning

Do not attempt to measure any of the high
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
screwdriver.)

3. High voltage is maintained within specified

limits by close-tolerance, safety-related
components and adjustments. If the high
voltage exceeds the specified limits, check
each of the special components.

Fig. 1-1 Discharging High Voltage Capacitor

Touch chassis ground first then short to the high
voltage capacitor terminal by using screwdriver or
jumper wire.

PRECAUTION

There exists HIGH VOLTAGE ELECTRICITY
with high current capabilities in the circuits of the
HIGH VOLTAGE TRANSFORMER secondary
and filament terminals. It is extremely dangerous
to work on or near these circuits with the oven
energized.
DO NOT measure the voltage in the high voltage
circuit including filament voltage of magnetron.

PRECAUTION

Never touch any circuit wiring with your hand nor
with uninsulated tool during operation.

PRECAUTION

Servicemen should remove their watches
whenever working close to or replacing the
magnetron.

Summary of Contents for AKM2800

Page 1: ...WAVE OVEN 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 Manual AKM2800 HOME APPLIANCES ...

Page 2: ...s and latches 5 evidence of dropping or abuse c Before turning on microwave power for any service test or inspection within the microwave generating compartments check the magnetron wave guide or transmission line and cavity for proper alignment integrity and connections d Any defective or misadjusted components in the interlock monitor door seal and microwave generation and transmission systems s...

Page 3: ...uld remove their watches while repairing an MWO 11 To avoid any possible radiation hazard replace parts in accordance with the wiring diagram Also use only the exact replacements for the following parts Primary and secondary interlock switches interlock monitor switch 12 If the fuse is blown by the Interlock Monitor Switch Replace all of the following at the same time Secondary door sensing switch...

Page 4: ...e 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 screwdriver 3 High voltage is maintained within specified limits by close tolerance safety related components and adjustments If the high voltage exceeds the specified ...

Page 5: ...R CONSUMPTION OUTPUT POWER OPERATING FREQUENCY MAGNETRON COOLING METHOD OUTSIDE DIMENSIONS mm NET WEIGHT SHIPPING WEIGHT 99 MINUTES 99SECONDS 110V 60Hz AC MICROWAVE 1 450W 1000W 10 LEVEL POWER 2 450MHz OM75P 31 ESS COOLING FAN MOTOR 517 W x 300 H x 380 D 15 3 kg 16 8 kg ...

Page 6: ...ing Instructions 3 1 Control Panel 3 2 Features External Views Door Ventilation Holes Light Safety Interlock Holes Control Panel Open Door Push Guide Roller Glass Tray Door Latches 517mm 369mm 300mm 216mm 380mm ...

Page 7: ...at 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 4 2 Replacement of High Voltage Transformer 1 Discharge the high voltage capacitor 2 Disconnect all the leads 3 Remove the mounting bolts 4 Reconnect the leads correctly and firmly PRECAU...

Page 8: ... remove the door assembly 4 3 2 Removal of Door E 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 3 Removal of Key Door Spring Remove pin hinge from Door E Detach spring from Door E and key door Door E Key Door Spring Door E Door A Door C ...

Page 9: ...eck if any other part such as the control circuit board blower motor or high voltage transformer is defective 4 5 Replacement of Drive Motor 1 Take out the glass tray guide roller from cavity 2 Turn the oven upside down to replace the drive motor 3 Remove a screw securing the drive motor cover or disconnect the drive motor cover from base plate by nipper 4 Disconnect all the lead wires from the dr...

Page 10: ...t board from the Ass y control box 4 When reconnecting the FPC connector make sure that the holes on the connector are properly engaged with the hooks on the Plastic Fastener 4 6 3 Removal of Window Display Membrane Panel 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 ...

Page 11: ...on from the circuit by disconnecting its leads 3 A continuity check across the magnetron filament terminals should indicate one ohm or less 4 A continuity check between each filament terminal and magnetron case should read open Primary Terminals Filament Terminals Secondary Terminal Magnetron Antenna Gasket Plate Cooling Fins PRECAUTION 1 High voltage is present at the high voltage terminals durin...

Page 12: ...No specific adjustment during installation of Primary switch Secondary 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 Comp...

Page 13: ...ds exactly 3 seconds included as a holding time of magnetron oscillation 4 When heating is finished stir the water again with the thermometer and measure the temperature T2 5 Subtract T1 from T2 This will give you the water temperature rise T 6 The output power is obtained by the following formula Output Power 4 187 x 1000 x T 0 55xMcx T2 T0 41 Heating Time sec 41 4 187 Coefficient for Water 1000 ...

Page 14: ... at the highest power level 4 Set survey meter dual ranges to 2 450MHz 5 Using the survey meter and spacer cone as described above measure near the opening of magnetron the surface of the air guide and the surface of the wave guide as shown in the following photo but avoid the high voltage components The reading should be less than 4mW cm 2 5 12 Note on Measurement 1 Do not exceed the limited scal...

Page 15: ...edure Replace PCB main Timer starts countdown but no microwave oscillation No heat while oven lamp and fan motor turn on 1 Off alignment of latch switches 2 Open or loose connection of high voltage circuit especially magnetron filament circuit NOTE Large contact resistance will bring lower magnetron filament voltage and cause magnetron to lower output and or intermittent oscillation 3 Defective hi...

Page 16: ... main Loud buzzing noise can be heard 1 Loose fan and fan motor 2 Loose screws on H V Transformer 3 Shorted H V Diode Tighten screws of fan motor Tighten screws of H V Transformer Replace H V Diode Turntable motor does not rotate 1 Open or loose wiring of turntable motor 2 Defective turntable motor Replace turntable motor Oven stops operation during cooking 1 Open or loose wiring of Secondary inte...

Page 17: ...ded Views MD06 MM01 MM22 MM16 MM07 MM03 MM13 MM29 MM30 MM31 MM14 MM18 MM19 MM20 MM27 MM28 MM55 MM05 MM06 MM17 MM08 MM10 MM09 MB01 MB05 MB03 MB08 MB04 MB02 MC01 MC05 MC04 MC02 MC03 MC07 MC13 MC06 MD01 MD02 MD10 MD07 MD04 MD11 MD05 MD03 MM32 MM88 ...

Page 18: ...60458A COVER AIR PP TB53 78G WHT 3RD 1 0 1 3 MW5896W 1 MM10 4713 001102 LAMP INCANDESCENT 125V 25W TRP 25x62mm 1 MM13 DE66 90113A LEVER DOOR PP TB53 GH41 T2 5 12g NTR 3RD W 1 MM14 DE26 00061D TRANS H V SHV U11KB 120V 60HZ 2240V 3 6V H 1 MM16 DE71 00015A COVER CEILING T0 3 W114 2 L121 5 CE2933 1 MM17 DE47 20032B THERMOSTAT PW2N 30 0 85 75 187 HORIZATAL 1 MM18 DE74 20015G TRAY COOKING T6 PI318 1115G...

Page 19: ... 1 MC07 RA N2LED1 08 ASSY PCB PARTS MW850 1 MC13 DE94 00095J ASSY CONTROL PANEL 120V60HZ MW1030WA P WHT S1 VE0812 1 MD01 ASSY DOOR 1 S N A MD02 DE64 40317U DOOR A AKM2800 ABS GENERAL T2 0 WHT NC1 0 1 MD03 DE67 20197C SCREEN DOOR MW1030WA PC T0 25 W210 4 L350 CLEAR 1 MD04 DE94 00075B ASSY DOOR E 3RD 1 0 BLK COATING 1 MD05 DE01 00118A FILM DOOR 1 MD06 DE64 40012A DOOR C RESIN PP TB53 T2 0 CE945GF BL...

Page 20: ... A 2S 4X12 TOOTHED 2 CN BOX DE60 10082H SCREW A 2S 4X12 TOOTHED 1 CV AIR DE60 10082H SCREW A 2S 4X12 TOOTHED 2 MGT TCO DE60 10082H SCREW A 2S 4X12 TOOTHED 2 MO FAN DE60 10082H SCREW A 2S 4X12 TOOTHED 1 P C EA DE60 10082H SCREW A 2S 4X12 TOOTHED 3 PN OUT DE60 10082H SCREW A 2S 4X12 TOOTHED 1 S M EA DE60 10098A SCREW ASSY TAP TITE GLD SWRCH18A ZPC2 PH TC M4X8 WT 2 M DRIV DE60 10195A SCREW STAR POLE ...

Page 21: ... 8 P C B Diagrams 8 1 P C B Diagrams ...

Page 22: ...T 89 3P 185MIL PLASTIC 1 IC02 1405 000001 VARISTOR 470V 1250A 14x7 5mm TP 1 ZNR1 2007 000033 R CHIP 0OHM 5 1 8W DA TP 3216 4 J11 12 13 16 2007 000282 R CHIP 100KOHM 5 1 10W DA TP 2012 2 R27 28 2007 000300 R CHIP 10KOHM 5 1 10W DA TP 2012 3 R07 08 09 2007 000346 R CHIP 120OHM 5 1 8W DA TP 3216 8 R19 26 2007 000468 R CHIP 1KOHM 5 1 10W DA TP 2012 6 R01 03 05 10 13 2007 000671 R CHIP 2KOHM 5 1 10W DA...

Page 23: ...D BLK BLK RED WHT ORG ORG BLU BLK MAGNETRON HIGH VOLTAGE DIODE TO CHASSIS FA F HIGH VOLTAGE TRANSFORMER POWER RELAY DOOR SENSING SWITCH BOTTOM MONITOR SWITCH CENTER BLK WHT SECONDARY SWITCH TOP HIGH VOLTAGE CAPACITOR RED ORG WHT SYMBOL COLOR BLU BLK RED ORANGE WHITE BLUE BLACK ...

Page 24: ...January 2003 Printed in Korea ...

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