Summary of DMO2420
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Dmo2420 microwave parts and service manual.
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1 dmo2420b dmo2420r dmo2420s warning to service personnel microwave ovens contain circuitry capable of pro- ducing very high voltage and current, contact with following parts may result in a severe, possibly fatal, electrical shock. (example) high voltage capacitor, high voltage power trans- former,...
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2 dmo2420b dmo2420r dmo2420s microwave measurement procedure a. Requirements: 1) microwave leakage limit (power density limit): the power density of microwave radiation emitted by a microwave oven should not exceed 1mw/cm 2 at any point 5cm or more from the external surface of the oven, measured pri...
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3 dmo2420b dmo2420r dmo2420s service manual microwave oven dmo2420b/dmo2420r/dmo2420s foreword this manual has been prepared to provide dacor service personnel with operation and service information for the dacor micro- wave ovens, dmo2420b, dmo2420r and dmo2420s. It is recommended that service pers...
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4 dmo2420b dmo2420r dmo2420s item description power requirements 120 volts / 13.8 amperes 60 hertz single phase, 3 wire grounded power output 1200 watts (iec test procedure) operating frequency of 2450mhz case dimensions width 24" height 13-3/8" depth 19-1/8" cooking cavity dimensions width 17-3/8" ...
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5 dmo2420b dmo2420r dmo2420s where a two-pronged wall-receptacle is encountered, it is the personal responsibility and obligation of the customer to contact a qualified electrician and have it replaced with a properly grounded three-pronged wall receptacle or have a grounding adapter properly ground...
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6 dmo2420b dmo2420r dmo2420s operation description of operating sequence the following is a description of component functions during oven operation. Off condition closing the door activates the door sensing switch and secondary interlock switch. (in this condition, the monitor switch contacts are o...
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7 dmo2420b dmo2420r dmo2420s the time of supplementary cooking is determined by experi- ment with each food category and inputted into the lsi. An example of how sensor works: (potatoes) 1. Potatoes at room temperature. Vapor is emitted very slowly. 2. Heat potatoes. Moisture and humidity is emitted...
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8 dmo2420b dmo2420r dmo2420s figure o-1. Oven schematic-off condition schematic note: condition of oven 1. Door closed. 2. Clock appears on display. Schematic note: condition of oven 1. Door closed. 2. Cooking time programmed. 3. Variable cooking control "p-hi/ 100 percent". 4. "start" pad touched. ...
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9 dmo2420b dmo2420r dmo2420s description and function of components door open mechanism the door is opened by pushing the open button on the control panel, refer to the figure d-1. When the open button is pushed, the open button pushes up the switch lever, and then the switch lever pushes up the lat...
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10 dmo2420b dmo2420r dmo2420s troubleshooting guide never touch any part in the circuit with your hand or an uninsulated tool while the power supply is connected. When troubleshooting the microwave oven, it is helpful to follow the sequence of operation in performing the checks. Many of the possible...
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11 dmo2420b dmo2420r dmo2420s ck = check / re = replace short in power cord short or opened wiring magnetron power transformer h.V. Rectifier assembly high voltage capacitor cavity temperature fuse magnetron temperature fuse primary interlock system secondary interlock switch monitor switch monitor ...
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12 dmo2420b dmo2420r dmo2420s b power transformer test 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor. 4. Disconnect the primary input terminals and measure the resistance of the transformer with an ohmmeter. C...
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13 dmo2420b dmo2420r dmo2420s test procedures procedure letter component test 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor. 4. If the capacitor is open, no high voltage will be available to the magnetron. Dis...
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14 dmo2420b dmo2420r dmo2420s test procedures procedure letter component test 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor. 4. Before performing this test, make sure that the secondary interlock switch and th...
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15 dmo2420b dmo2420r dmo2420s h blown monitor fuse test test procedures procedure letter component test 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor. 4. If the monitor fuse is blown when the door is opened, c...
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16 dmo2420b dmo2420r dmo2420s 4) reconnect the power supply cord after the outer case is installed. 5) run the oven and check all functions. The following symptoms indicate a defective key unit. A) when touching the pads, a certain pad produces no signal at all. B) when touching a number pad, two fi...
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17 dmo2420b dmo2420r dmo2420s test procedures procedure letter component test may be used (after clearing the control unit) to determine if the control unit or key pad is at fault. 5. Reconnect all leads removed from components during testing. 6. Re-install the outer case (cabinet). 7. Reconnect the...
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18 dmo2420b dmo2420r dmo2420s to protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on the pwb, this foil pattern acts as a fuse. 1. Foil pattern check and repairs. 1) disconnect the power supply cord, and then remove outer case. 2) open the door an...
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19 dmo2420b dmo2420r dmo2420s test procedures procedure letter component test 10) discharge high voltage capacitor. 11) reconnect all leads removed from components during testing. 12) re-install the outer case (cabinet). 13) reconnect the power supply cord after the outer case is installed. 14) run ...
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20 dmo2420b dmo2420r dmo2420s test procedures procedure letter component test 9-3. Close the door. 9-4. Touch the timer/clock pad once, the power level pad twice, the start pad once and the number pad 1 once. 9-5. The control panel is in automatic sensor operation. 9-6. And then the oven will turn o...
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21 dmo2420b dmo2420r dmo2420s touch control panel assembly outline of touch control panel 4) relay circuit a circuit to drive the magnetron, fan motor, turntable motor and light the oven lamp. 5) buzzer circuit the buzzer is responsive to signals from the lsi to emit audible sounds (key touch sound ...
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22 dmo2420b dmo2420r dmo2420s lsi(ixa098dr) the i/o signal of the lsi(ixa098dr) is detailed in the following table. Pin no. Signal i/o description 1 com5 out common data signal : com11. Connected to lcd signal com11. 2 com4 out common data signal : com12. Connected to lcd signal com12. 3 com3 out co...
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23 dmo2420b dmo2420r dmo2420s 34 int0 in signal synchronized with commercial power source frequency. This is the basic timing for time processing of lsi. 35 p07 out key strobe signal. Signal applied to touch-key section. A pulse signal is input to ain7, p14, p15, p16 and p17 terminal while one of g1...
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24 dmo2420b dmo2420r dmo2420s 52 nc _ terminal not used. 53 xcout out terminal not used. 54 xcin in connected to vc. 55 nc _ terminal not used. 56 vcc in power source voltage: gnd(0v). The power source voltage to drive lsi is input to vcc terminal. 57 oscsel in connected to vc(-5v). 58 xout out inte...
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25 dmo2420b dmo2420r dmo2420s absolute humidity sensor circuit (1) structure of absolute humidity sensor the absolute humidity sensor includes two thermistors as shown in the illustration. One thermistor is housed in the closed vessel filled with dry air while another in the open vessel. Each sensor...
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26 dmo2420b dmo2420r dmo2420s 1. Precautions for handling electronic components this unit uses cmos lsi in the integral part of the circuits. When handling these parts, the following precautions should be strictly followed. Cmos lsi have extremely high impedance at its input and output terminals. Fo...
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27 dmo2420b dmo2420r dmo2420s to remove the outer case, proceed as follows. 1. Disconnect the power supply cord. 2. Open the oven door and block it open. 3. Remove the two (2) screws from the lower portion of the rear cabinet using a t20h torx type or gtxh20-100 screw driver. 4. Remove the remaining...
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28 dmo2420b dmo2420r dmo2420s power transformer removal reinstallation 1. Rest transformer on the bottom plate with its primary terminals toward the oven face plate. 2. Secure transformer with four screws to bottom plate. 3. Re-connect wire leads (primary and high voltage) to power transformer and f...
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29 dmo2420b dmo2420r dmo2420s control panel assembly removal positive lock ® connector (no-case type) removal figure c-2. Positive lock ® connector 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor. 4. Push the le...
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30 dmo2420b dmo2420r dmo2420s cooling fan motor removal removal 1. Disconnect the power supply cord and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor. 4. Disconnect the wire leads from the fan motor. 5. Remove the two (2) screws holding the fan motor...
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31 dmo2420b dmo2420r dmo2420s door replacement 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor. If the door sensing switch, secondary interlock switch and monitor switch do not operate properly due to a misadjus...
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32 dmo2420b dmo2420r dmo2420s note: the door on a microwave oven is designed to act as an electronic seal preventing the leakage of microwave energy from oven cavity during cook cycle. This function does not require that door be air- tight, moisture (condensation)-tight or light-tight. Therefore, oc...
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33 dmo2420b dmo2420r dmo2420s 6 45 1 2 3 6 45 1 2 3 a b c d e f g h a b c d e f g h figure s-1. Pictorial diagram high voltage capacitor high voltage wire a h.V. Rectifier power supply cord 120v 60hz high voltage components oven lamp and socket magnetron com. Monitor switch com. N.O. N.C. Door sensi...
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34 dmo2420b dmo2420r dmo2420s 6 4 5 1 2 3 6 4 5 1 2 3 a b c d e f g h a b c d e f g h figure s-2. Power unit circuit + – + – + – a 1 cn-a r4 27 d5 t1 1 3 4 d1 d3 d2 d4 6 a b c d vrs1 (j1) d7 d8 1ss270a 1ss270a 10g471k c1 0.1 µ /50v c3 0.1 µ /50v zd1 hz16-1 c5 10 µ /35v c2 1000 µ /35v c4 10 µ /35v r1...
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35 dmo2420b dmo2420r dmo2420s 6 45 1 2 3 6 45 1 2 3 a b c d e f g h a b c d e f g h fresh vegetables beverage breakfast lunch popcorn snacks microwave recipes start instant on fish seafood power level keep warm 15 minute dinner auto defrost help guide baked potatoes reheat easy minute vegetables ric...
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36 dmo2420b dmo2420r dmo2420s 6 4 5 1 2 3 6 4 5 1 2 3 a b c d e f g h a b c d e f g h figure s-4. Printed wiring board of power unit wh - 1 sh - b sh - a 1 c3 c4 c5 r3 c2 f c1 10 d4 d2 d1 d3 (j1) d9 (d10) ry3 (cn - d) d8 zd1 vrb d u r2 r1 r6 r5 sp1 3 e b d6 d5 q2 r4 2 6 11 p s ry2 t1 ac vrs1 5 d7 om...
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Technical service 950 s. Raymond ave. Pasadena, ca 91105 800-353-2267 part # 85927.