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R-21JCA

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, Magnetron, High Voltage Rectifier Assem-
bly,  High Voltage Harness etc..

Read the Service Manual carefully and follow all
instructions.

Before Servicing

1. Disconnect the power supply cord          , and then remove

outer case.

2. Open the door and block it open.
3. Discharge high voltage capacitor.

WARNING:RISK OF ELECTRIC SHOCK.

DISCHARGE THE HIGH-VOLTAGE
CAPACITOR BEFORE SERVICING.

The high-voltage capacitor remains charged about 60
seconds after the oven has been switched off. Wait for 60
seconds and then short-circuit the connection of the high-
voltage capacitor (that is the connecting lead of the high-
voltage rectifier) against the chassis with the use of an
insulated screwdriver.

Whenever troubleshooting is performed the power supply
must be disconnected. It may in, some cases, be necessary
to connect the power supply after the outer case has been
removed, in this event,
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 leads to the primary of the power

transformer.

5. Ensure that the leads remain isolated from other

components and oven chassis by using insulation tape.

6. After that procedure, reconnect the power supply cord.

When the testing is completed,
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. Reconnect the leads to the primary of the power

transformer.

5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is

installed.

7. Run the oven and check all functions.

After repairing

1. Reconnect all leads removed from components during

testing.

2. Reinstall the outer case (cabinet).
3. Reconnect the power supply cord after the outer case is

installed.

4. Run the oven and check all functions.

Microwave ovens should not be run empty. To test for the
presence of microwave energy within a cavity, place a cup
of cold water on the oven turntable, close the door and set
the power to HIGH and set the microwave timer for two (2)
minutes. When the two minutes has elapsed (timer at zero)
carefully check that the water is now hot. If the water
remains cold carry out Before Servicing procedure and re-
examine the connections to the component being tested.

When all service work is completed and the oven is fully
assembled, the microwave power output should be checked
and a microwave leakage test should be  carried out.

Don't Touch !
Danger High Voltage

Summary of Contents for R21JCA - Commercial Microwave Oven

Page 1: ...in a severe possibly fatal electrical shock High Voltage Capaci tor High Voltage Power Transformer Magnetron High Volt age Rectifier Assembly High Voltage Harness etc SHARP CORPORATION This document has been published to be used for after sales service only The contents are subject to change without notice SUPPLEMENTAL SERVICE MANUAL This is a supplemental Service Manual for Model R 21JCA This mod...

Page 2: ...ransmission systems shall be repaired replaced or adjusted by procedures described in this manual before the oven is released to the owner e A microwave leakage check to verify compliance with the Federal Performance Standard should be performed on each oven prior to release to the owner BEFORE SERVICING Before servicing an operative unit perform a microwave emission check as per the Microwave Mea...

Page 3: ...citor 4 Disconnect the leads to the primary of the power transformer 5 Ensure that the leads remain isolated from other components and oven chassis by using insulation tape 6 After that procedure reconnect the power supply cord When the testing is completed 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 Reconnect...

Page 4: ...e oven cavity The water container shall be a low form of 600 ml 20 oz beaker with an inside diameter of approx 8 5 cm 3 1 2 in and made of an electrically nonconductive material such as glass or plastic The placing of this standard load in the oven is important not only to protect the oven but also to insure that any leakage is measured accurately 4 Set the cooking control on Full Power Cooking Mo...

Page 5: ...e oven until the following points are ensured A The door is tightly closed B The door brackets and hinges are not defective C The door packing is not damaged D The door is not deformed or warped E There is no other visible damage with the oven Servicing and repair work must be carried out only by trained service personnel DANGER Certain initial parts are intentionally not grounded and present a ri...

Page 6: ...ent to a voltage doubler circuit OPERATION DESCRIPTION OF OPERATING SEQUENCE 4 The microwave energy produced by the magnetron is channelled through the waveguide into the cavity feed box and then into the cavity where the food is placed to be cooked 5 Upon completion of the cooking time the power transformer oven lamp etc are turned off and the generation of microwave energy is stopped The oven wi...

Page 7: ...nsists of circuits including semiconductors such as LSI ICs etc Therefore unlike conventional microwave ovens proper maintenance cannot be performed with only a voltmeter and ohmmeter In this service manual troubleshooting by unit replacement is described according to the symptoms indicated Before testing 1 Disconnect the power supply cord and then remove outer case 2 Open the door and block it op...

Page 8: ...hould indicate 120 volts if not check oven circuit RY1 AND RY2 Relay Test These relays are operated by D C voltage Check voltage at the relay coil with a D C voltmeter during the microwave cooking operation DC voltage indicated Defective relay DC voltage not indicated Check diode which is connected to the relay coil If diode is good control unit is defective RELAY SYMBOL OPERATIONAL VOLTAGE CONNEC...

Page 9: ...citor 4 Disconnect the leads to the primary of the power transformer 5 Ensure that these leads remain isolated from other components and oven chassis by using insulation tape 6 After that procedure re connect the power supply cord 7 Follow the troubleshooting guide given below for repair STEPS OCCURRENCE CAUSE OR CORRECTION The rated AC voltage is not present between 1 Pin No 5 of the 3 pin connec...

Page 10: ...ound 6 Door Sensing Switch A switch to tell the LSI if the door is open or closed 7 Relay Circuit To drive the magnetron fan motor antenna motor and light the oven lamp 8 Encoder The encoder generates the pulse signal and the pulse signal is sent to the LSI 9 Indicator Circuit Indicator elements are the Light emitting diodes LD1 LD20 This circuit consists of 4 digits and 5 segments DESCRIPTION OF ...

Page 11: ...nput signal which communicates the door open close information to LSI Door closed L level signal Door opened H level signal 19 21 AIN1 AIN3 IN Terminal to change functions according to the model Signal in accordance with the model in operation is applied to set up its function 22 P00 OUT Terminal not used 23 P01 OUT Magnetron high voltage circuit driving signal To turn on and off the cook relay RY...

Page 12: ...wo can t be separated For those models check and repair all the controls sensor related ones included of the touch control panel while keeping it connected to the oven B On some models the power supply cord between the touch control panel and the oven proper is so long enough that they may be separated from each other For those models therefore it is possible to check and repair the controls of th...

Page 13: ...arped 5 There are defective parts in the door interlock system 6 There are defective parts in the microwave generating and transmission assembly 7 There is visible damage to the oven Do not operate the oven 1 Without the RF gasket Magnetron 2 If the wave guide or oven cavity are not intact 3 If the door is not closed 4 If the outer case cabinet is not fitted 3 Sharp edge Bottom plate Oven cavity W...

Page 14: ...e NOTE At this moment the door badge is attached on the door case RE INSTALL OF THE DOOR 1 Re install all door parts except the choke cover 2 Catch two 2 pins of door panel on two 2 holes of upper and lower oven hinges 3 Re install choke cover to door panel by pushing NOTE After any service to the door A Make sure that door sensing switch and secondary interlock switch are operating properly Refer...

Page 15: ... Antenna Assembly Figure C 10 Stirrer Antenna Assembly Installation Screw Square hole Screw Antenna motor Antenna motor shaft Antenna holder Stirrer antenna Oven cavity bottom plate Tab Washer 3 Hook the hole of the antenna holder on the tab of the oven cavity bottom plate Refer to Figure C 10 4 Insert the antenna holder into the hole of the oven cavity bottom plate and fit the hole of the antenna...

Page 16: ...60Hz N O OVEN LAMP ANTENNA MOTOR FAN MOTOR N O RY2 Q22 KRC105S RY1 D22 D20 D30 4 7K 47K R31 R30 C30 D21 R21 4 7K Q20 KRC101S 4 7K R22 C21 10µ 35V 0 1µ 50V C20 R20 4 7K Q21 KRA101S HZ11A3 x 3 ZD3 ZD2 ZD1 1W 510 x 2 R3 1W 1K KTC3198A HZ6C3 x 2 ZD5 ZD4 KTA1504 R6 4 7K HZ4C1 ZD6 4 7K R10 D11 D10 0 1µ 50V 27K Q40 KRC101S SP1 R41 1 5K R42 3 3K 27K 27K R40 4 7K 220µ 16V C5 J3 J5 6 2K J7 J6 4 7K J4 4 7K J...

Page 17: ...JP2 C21 JP3 CNC Q1 E B JP14 JP20 JP18 JP9 JP19 JP7 ZD1 ZD5 ZD4 ZD2 ZD3 D10 D11 D20 D21 JP17 JP13 JP8 JP1 R3 SP1 CF1 JP16 JP15 JP32 JP25 1 2 3 4 5 6 8 9 10 11 12 13 14 7 JP35 JP37 LD8 LD9 LD10 LD11 LD12 LD13 LD14 LD15 LD16 LD17 LD18 LD19 LD20 LD1 LD2 LD3 LD4 LD5 LD6 LD7 SW1 JP29 JP24 JP27 JP28 JP33 JP26 D84 D83 D75 D79 D82 D85 B C A ZD6 R2 C5 C3 R1 C1 D1 D3 D4 D2 J1 D22 CNA VRS1 SW2 D30 WHA WHA R12...

Page 18: ...0WRP0 C P case 1 BA 3 3 TCAUAA076WRR0 User caution label 1 AB 3 4 JKNBKA606WRM0 Timer knob 1 AL 3 5 XEPSD30P08XS0 Screw 3mm X 8mm 5 AA OVEN PARTS 4 1 FGLSPA062WRE0 Ceramic shelf 1 BL 4 2 Oven cavity Not a replaceable part 1 4 3 MLEVPA227WRF0 Latch switch lever A 1 AF 4 4 MLEVPA228WRF0 Latch switch lever B 1 AF 4 5 MLEVPA229WRF0 Latch switch lever C 1 AF 4 6 MSPRCA108WRE0 Latch lever spring 3 AC 4 ...

Page 19: ...8mm 4 AB 5 1 17 XEPSD40P25K00 Screw 4mm x 25mm 2 AB 5 1 18 PCUSUA508WRP0 Cushion 1 AC 5 2 GCOVHA407WRF0 Choke cover 1 AM 5 3 HBDGCA107WREZ Door badge 1 AL MISCELLANEOUS 6 1 TINSEA954WRRZ Instruction book 1 AM 6 2 FW VZB684WRE0 Main wire harness 1 BB 6 3 TCAUAA166WRR0 DHHS caution label 1 AB 6 4 TCAUAA241WRR0 Monitor caution 1 AE 6 5 TCAUAA243WRR0 Earth caution 1 AC 6 6 TCAUAA245WRR0 Cover caution ...

Page 20: ...4 35 4 39 7 11 7 11 2 5 4 7 1 1 4 6 4 6 7 7 4 30 4 24 4 24 2 4 4 10 6 7 2 1 4 14 4 20 7 1 4 8 2 3 7 8 7 11 4 11 1 14 1 2 4 29 4 20 4 22 4 34 7 3 4 25 7 3 7 1 1 4 6 3 6 6 1 12 1 4 4 24 4 36 7 7 7 9 7 8 7 2 1 7 7 1 1 6 2 4 4 17 4 41 2 2 4 13 4 12 4 31 7 11 7 10 4 26 4 26 4 2 4 19 4 23 4 21 4 21 4 21 4 1 7 6 7 13 7 13 7 13 4 9 4 32 4 18 4 16 1 10 1 9 4 28 6 5 x2 4 40 6 9 4 27 4 20 4 20 4 37 4 38 ...

Page 21: ...2 3 3 3 2 1 3 2 3 1 3 5 3 5 3 4 Actual wire harness may be different from illustration 5 1 6 5 2 5 1 4 5 6 2 5 1 15 5 1 7 5 1 8 5 1 8 5 1 9 5 1 13 5 1 17 5 1 11 5 1 3 5 1 4 1 5 1 1 5 1 4 5 5 1 12 5 1 12 5 1 14 5 1 18 5 1 4 5 1 17 5 1 2 5 1 16 5 1 16 5 1 16 5 1 16 x4 x2 6 8 5 3 5 1 5 1 5 5 1 10 5 1 4 3 5 1 4 4 5 1 4 2 ...

Page 22: ...TRUCTION BOOK TOP PAD ASSEMBLY FPADBA385WRK0 BOTTOM PAD ASSEMBLY FPADBA386WRK0 WRAP COVER SSAKHA034WRE0 DOOR PROTECTION SHEET SPADPA204WRE0 PACKING CASE SPAKCD803WREZ Not Replaceable Items TRAY HOLDER SPADFA435WRE0 Into the Oven Cavity 6 1 ...

Page 23: ...21 R 21JCA ...

Page 24: ...BY SHARP CORPORATION ALL RIGHTS RESERVED No part of this publication may be reproduced stored in retrieval systems or transmitted in any form or by any means electronic mechanical photo copying recording or otherwise without prior writ ten permission of the publisher ...

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