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8

R-305BW
R-309BW

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
latch head. The latch heads are moved upward and re-
leased from latch hook. Now the door will open.

Latch Hook

Door
Sensing 
Switch

Monitor
Switch

Secondary
Interlock
Switch

Switch
Lever

Latch
Heads

Door

Figure D-1. Door Open Mechanism

DOOR SENSING AND SECONDARY INTERLOCK
SWITCHES

The secondary interlock switch is mounted in the lower
position of the latch hook and the door sensing switch in the
primary interlock system is mounted in the upper position of
the latch hook. They are activated by the latch heads on the
door. When the door is opened, the switches interrupt the
power to all high voltage components. A cook cycle cannot
take place until the door is firmly closed thereby activating
both interlock switches. The primary interlock system con-
sists of the door sensing switch and primary interlock relay
located on the control circuit board.

MONITOR SWITCH

The monitor switch is activated (the contacts opened) by the
latch head on the door while the door is closed. The switch
is intended to render the oven inoperative, by means of
blowing the monitor fuse, when the contacts of the primary
interlock relay (RY2) and secondary interlock switch fail to
open when the door is opened.

Functions:
1. When the door is opened, the monitor switch contact

close (to the ON condition) due to their being normally
closed. At this time the primary interlock relay (RY2) and
secondary interlock switch are in the OFF condition
(contacts open) due to their being normally open contact
switches.

2. As the door goes to a closed position, the monitor switch

contacts are first opened and then the door sensing
switch and the secondary interlock switch contacts close.
(On opening the door, each of these switches operate
inversely.)

3. If the door is opened, and the primary interlock relay

(RY2) and secondary interlock switch contacts fail to
open, the monitor fuse blows simultaneously with closing
of the monitor switch contacts.

CAUTION: BEFORE REPLACING A BLOWN MONITOR

FUSE TEST THE DOOR SENSING SWITCH,
PRIMARY INTERLOCK RELAY (RY2), RELAY
(RY1), SECONDARY INTERLOCK SWITCH
AND MONITOR SWITCH FOR PROPER OP-
ERATION. (REFER TO CHAPTER "TEST PRO-
CEDURE").

NOTE: MONITOR FUSE AND MONITOR SWITCH ARE

REPLACED AS AN ASSEMBLY.

TURNTABLE MOTOR

The turntable motor rotates the turntable located on the
bottom of the oven cavity, so that the foods on the turntable
cook evenly during cooking. The turntable may turn in either
direction.

COOLING FAN MOTOR

The cooling fan motor drives a blade which draws external
cool air. This cool air is directed through the air vanes
surrounding the magnetron and cools the magnetron. This
air is channelled through the oven cavity to remove steam
and vapors given off from the heating foods. It is then
exhausted through the exhausting air vents at the oven
cavity.

MONITOR FUSE

1. The monitor fuse blows when the contacts (COM-NO) of

the primary interlock relay (RY2) and secondary interlock
switch remain closed with the oven door open and when
the monitor switch closes.

2. If the wire harness or electrical components are short-

circuited, this monitor fuse blows  to prevent an electric
shock or fire hazard.

OVEN THERMAL CUT-OUT

The thermal cut-out, located on the top of the oven cavity, is
designed to prevent damage to the oven by fire. If the foods
load is overcooked, by either error in cook time or defect in
the control unit, the thermal cut-out will open.
Under normal operation, the oven thermal cut-out remains
closed. However, when abnormally high temperatures are
reached within the oven cavity, the oven thermal cut-out will
open at 257˚F(125˚C), causing the oven to shut down.

MAGNETRON  THERMAL CUT-OUT

The thermal cut-out located near the magnetron is designed
to prevent damage to the magnetron if an over heated
condition develops in the tube due to cooling fan failure,
obstructed air guide, dirty or blocked air intake, etc.
Under normal operation, the thermal cut-out remains closed.
However, when abnormally high temperatures are reached
within the magnetron, the thermal cut-out will open at
203˚F(95˚C) causing the oven to shut down.

Содержание R-305B-W

Страница 1: ...RVICE PERSONNEL 1 MICROWAVE MEASUREMENT PROCEDURE 2 FOREWORD AND WARNING 3 PRODUCT SPECIFICATIONS 4 GENERAL INFORMATION 4 OPERATION 6 TROUBLESHOOTING GUIDE 9 TEST PROCEDURE 10 TOUCH CONTROL PANEL 18 COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE 22 PICTORIAL DIAGRAM 28 POWER UNIT CIRCUIT 29 CPU UNIT CIRCUIT 30 PRINTED WIRING BOARD 32 PARTS LIST 33 PACKING AND ACCESSORIES 37 S1801R305BPW R 305BW R ...

Страница 2: ...ion and transmission 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 releasing to the owner BEFORE SERVICING Before servicing an operative unit perform a microwave emission check as per the Mi...

Страница 3: ...e 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 Rec...

Страница 4: ...he center of the 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 Theplacingofthisstandardloadintheovenisimportantnotonlytoprotecttheoven butalsotoinsurethatanyleakage is measured accurately 4 Set the cooking control on Full Power Cooking Mode 5 Cl...

Страница 5: ... is not damaged D The door is not deformed or warped E There is not any other visible damage with the oven Servicing and repair work must be carried out only by trained service personnel DANGER Certaininitialpartsareintentionallynotgroundedandpresent a risk of electrical shock only during servicing Service personnel Do not contact the following parts while the appliance is energized HighVoltageCap...

Страница 6: ... throughout the cooking time INSTANT START pads COMPU DEFROST pad Number selection pads POWER LEVEL pad TIMER CLOCK pad STOP CLEAR pad START MINUTE PLUS pad Oven Cavity Light Yes Safety Standard UL Listed FCC Authorized DHHS Rules CFR Title 21 Chapter 1 Subchapter J SPECIFICATION GENERAL INFORMATION GROUNDING INSTRUCTIONS This oven is equipped with a three prong grounding plug It must be plugged i...

Страница 7: ...s the door is securely closed 3 Removable turntable support 4 Removable turntable The turntable will rotate clockwise or counterclockwise 5 Oven lamp It will light when oven is operating or door is opened 6 Oven door with see through window 7 Ventilation openings Rear 8 Auto Touch control panel 9 Time display Digital display 99 minutes 99 seconds 10 Coupling 11 Wave guide cover 12 Power supply cor...

Страница 8: ...tor the cooling fan motor and the high voltage components are de energized the oven lamp remains on and the digital read out displays the time still remaining in the cook cycle when the door was opened 7 The monitor switch electrically monitors the operation of the secondary interlock switch and primary interlock relay and is mechanically associated with the door so that it will function in the fo...

Страница 9: ...SWITCH RECTIFIER MAGNETRON SECONDARY INTERLOCK SWITCH TTM OL FM MONITOR FUSE A1 A2 COM COM N O N O DOOR SENSING SWITCH RY 1 RY 2 CONTROL UNIT PRIMARY INTERLOCK RELAY THERMAL CUT OUT OVEN THERMAL CUT OUT MG SH B SH A GRN 20A for R 309BW 15A for R 305BW OVEN LAMP TURN TABLE MOTOR FAN MOTOR POWER TRANSFORMER MONITOR SWITCH RECTIFIER MAGNETRON SECONDARY INTERLOCK SWITCH TTM OL FM COM N O DOOR SENSING ...

Страница 10: ... RY2 and secondary interlock switch contacts fail to open themonitorfuseblowssimultaneouslywithclosing of the monitor switch contacts CAUTION BEFORE REPLACING A BLOWN MONITOR FUSE TEST THE DOOR SENSING SWITCH PRIMARY INTERLOCK RELAY RY2 RELAY RY1 SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH FOR PROPER OP ERATION REFERTOCHAPTER TESTPRO CEDURE NOTE MONITOR FUSE AND MONITOR SWITCH ARE REPLACED AS AN...

Страница 11: ...BW FFS BA012WRK0 for R 309BW as an assembly IMPORTANT Wherever troubleshooting is performed with the power supply cord disconnected It may in some cases be necessary to connect the power supply cord 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 l...

Страница 12: ...oper ate Oven does not go into cook cycle when START pad is touched Oven seems to be operating but little or no heat is produced in oven load Food incompletely cooked or not cooked at all at end of cook cycle Oven goes into a cook cycle but extremely uneven heating is pro duced in oven load food Oven does not cook properly when programmed for Cooking Power 5 mode Operates prop erlyonCookingPower10...

Страница 13: ... a water temperature rise test This test shouldonlybeusedifabovetestsdonotindicateafaultymagnetronandthereisnodefectinthefollowing componentsorwiring siliconrectifier highvoltagecapacitorandpowertransformer Thistestwillrequire a 16 ounce 453cc measuring cup and an accurate mercury thermometer or thermocouple type temperature tester For accurate results the following procedure must be followed care...

Страница 14: ...cially the cooling fan and air guide 5 Reconnect all leads removed from components during testing 6 Reinstall the outer case cabinet 7 Reconnect the power supply cord after the outer case is installed 8 Run the oven and check all functions MAGNETRON THERMAL CUT OUT TEST 1 Disconnect the power supply cord and then remove outer case 2 Open the door and block it open 3 Discharge high voltage capacito...

Страница 15: ... switch 5 Reconnect all leads removed from components during testing 6 Reinstall the outer case cabinet 7 Reconnect the power supply cord after the outer case is installed 8 Run the oven and check all functions PRIMARY INTERLOCK SYSTEM TEST DOOR SENSING SWITCH 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 Isolat...

Страница 16: ...ns The touch control panel consists 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 the touch control panel assembly is divided into two units Control Unit and Key Unit and also the Control Unit is divided into two units CPU Unit and Power Unit and...

Страница 17: ... g The figure of all digits flicker 2 3 Other possible problems caused by defective control unit a Buzzer does not sound or continues to sound b Clock does not operate properly c Cooking is not possible When 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 all leads removed from compo...

Страница 18: ... G 5 G 4 G 3 G 2 G 1 G12 G11 G10 G 9 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 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 Remov...

Страница 19: ...Run the oven and check all function 2 Follow the troubleshooting guide given below if indicator does not light up after above check and repairs are finished 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 these leads remain isolated from ot...

Страница 20: ...ts the LSI to the initial state when power is supplied 2 Indicator Circuit This circuit consists of 12 segments and 3 common elec trodes using a Liquid Crystal Display 3 Power Source Circuit This circuit generates voltages necessary in the control unit from the AC line voltage In addition the synchronizing signal is available in order to compose a basic standard time in the clock circuit Symbol Vo...

Страница 21: ... is touched a corresponding signal will be input into R63 17 AIN0 IN To input signal which communicates the door open close information to LSI Door close H level signal 0V Door open L level 5V 18 20 AIN1 AIN3 IN Terminal to change functions according to the Model By using the A D converter contained in the LSI DC voltage in accordance with the Model in operation is applied to set up its function 2...

Страница 22: ...minal while one of G3 line keys on key matrix is touched 32 R92 OUT Terminal not used 33 XIN IN Internal clock oscillation frequency setting input The internal clock frequency is set by inserting the capacitor and resistor circuit with respect to XOUT terminal 34 XOUT OUT Internal clock oscillation frequency control output Output to control oscillation input of XIN 35 RESET IN Auto clear terminal ...

Страница 23: ...controlpanelandtheovenitselfissoshortthatthetwocan 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 After checking the performance of the touch control panel B On some models the power supply cord between the touch control panel and the oven proper is long enough that they may be separat...

Страница 24: ...G FOR WIRING 1 Disconnect the power supply cord 2 Make sure that a definite click can be heard when the microwave oven door is unlatched Hold the door in a closed position with one hand then push the door open button with the other this causes the latch leads to rise it is then possible to hear a click as the door switches operate 3 Visuallycheckthedoorandcavityfaceplatefordamage dents cracks sign...

Страница 25: ...eptacle into terminal insulator 2 Close covers of the terminal insulator as shown below 3 Reconnect all leads removed from components during testing 4 Reinstall the outer case cabinet 5 Reconnect the power supply cord after the outer case is installed 6 Run the oven and check all functions Terminal insulator Flat type screw driver RECEPTACLE COVERS TERMINAL INSULATOR REPLACEMENT Special screw Scre...

Страница 26: ...chassis support to magnetron 6 Remove the chassis support from oven 7 Carefully remove the four 4 screws holding magnetron to waveguide flange 8 Lift up magnetron with care so that magnetron antenna is not hit by any metal object around antenna 9 Now the magnetron is free Re install 1 Re install the magnetron to waveguide flange with the four 4 screws as shown in Figure C 1 2 Insert the two 2 tabs...

Страница 27: ...Install the fan blade to the shaft of fan motor by pushing thefanbladewithasmall lightweight ballpeenhammer or rubber mallet CAUTION Do not hit the fan blade strongly when installed because the bracket may be disfigured Make sure that the fan blade rotates smooth after installation Make sure that the axis of the shaft is not slanted 6 Catch three holes of fan duct on three tabs of the waveguide fl...

Страница 28: ...ontacts close when door is opened 4 Re install outer case and check for microwave leakage around door with an approved microwave survey meter Refer to Microwave Measurement Procedure Latch Hook Door Sensing Switch Monitor Switch Secondary Interlock Switch Switch Lever Latch Heads Door Figure C 6 Latch Switch Adjustments Side View Rear View Shaft Table Center of bracket 1 Disconnect the power suppl...

Страница 29: ... to Sealer Film about how to handle new one 6 Catch two 2 pins of door panel on two 2 hole of upper and lower oven hinges 7 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 to chapter Test Procedures B An approved microwave survey meter should be used to assure complia...

Страница 30: ...N POWER TRANSFORMER COM NO CN A 1 2 WHT NOTE The grounding conductor of the power supply cord has been grounded by power supply cord fixing screw The screw must allways be kept tight NOTE The neutral WHT wire must be connected to the terminal with N mark on the power supply cord BLK GRY RED WHT YLW WHT BLK GRY GRN GRY GRN R E D WHT GRY BLK BLK BLK WHT COM RED RED N O RY2 YLW BLK COM YLW YLW N O RY...

Страница 31: ...4 3 6 AC AC SH B SH A MICRO DOOR SWITCH NOTE IF NOT SPECIFIED 1 4w 5 IF NOT SPECIFIED 1SS270A TURNTABLE MOTOR OVEN LAMP FAN MOTOR WH 1 R4 27 R5 4 7k R3 820 1 2w R2 820 1 2w R6 3 3k SP1 VRS1 C1 0 1µ 50v C5 10µ 35v C2 1000µ 35v C4 10µ 35v J1 D5 D3 D4 D2 D1 a c d b D6 RY1 D7 D8 RY2 Q2 2SB1238 D1 D4 11ES1 Q3 DTD143ES VR VR LD1 LD5 LD1 LD2 LD3 LD4 LD5 N O N O COM COM ...

Страница 32: ...3 15k D10 R11 15k R71 10kF R10 1k ZD10 UDZ4 3B J11 J13 J15 4 7k x 3 Q10 2SA1037AK C10 0 01µ 25v C12 0 01µ 25v 0 01µ 25v C40 C71 IC1 IZA828DR C11 47µ 16v C13 0 1µ 50v C70 0 01µ 25v R12 15k NC GND VC INT BUZZER RY1 RY2 RY3 DOOR SWITCH NOTEH IF NOT SPECIFIED 1 10w 5 IF NOT SPECIFIED 1SS355 LIQUID CRYSTAL DISPLAY KEY UNIT ON DEF LBS QTY CHECK R57 15k R58 15k R59 15k R60 15k R40 15k R80 15k D20 MA512WA...

Страница 33: ... C61 330p 50v R13 15k D10 R11 15k R71 10kF R10 1k ZD10 UDZ4 3B J11 J13 J15 4 7k x 3 Q10 2SA1037AK C10 0 01µ 25v C12 0 01µ 25v 0 01µ 25v C40 C71 IC1 IZA758DR C11 47µ 16v C13 0 1µ 50v C70 0 01µ 25v R12 15k NC GND VC INT BUZZER RY1 RY2 RY3 DOOR SWITCH NOTEH IF NOT SPECIFIED 1 10w 5 IF NOT SPECIFIED 1SS355 LIQUID CRYSTAL DISPLAY KEY UNIT ON DEF LBS QTY CHECK R57 15k R80 15k R58 15k R59 15k R60 15k R40...

Страница 34: ...rd of Power Unit WH 1 WH 1 SH B SH A LD1 DIP LD2 1 C3 C4 C5 R3 C2 F C1 10 D4 D2 D1 D3 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 QKITPB026MRE0 5 D7 OMIF D U 9 8 7 E Q1 B 4 E RY1 AC OL TTM FM B Q3 CN C CN C CN B CN A LD3 LD4 LD5 1 1 1 9 12 2 1 1 1 2 XA VH 2 2 ...

Страница 35: ...mer R 309BW 1 BK 1 14 RTRN A525WRE0 Power transformer Interchangeable R 309BW 1 BM CABINET PARTS 2 1 GCABUA649WRP0 Outer case cabinet 1 AZ 2 2 GDAI A261WRW0 Bottom left plate 1 AP 2 3 GDAI A286WRW0 Bottom right plate 1 AN 2 4 GLEGPA019WRE0 Foot 2 AD 2 5 GLEGPA067WRF0 Leg 1 AE CONTROL PANEL PARTS 3 1 CPWBFA766WRK0 Power unit 1 BD 3 1A QCNCMA446DRE0 2 pin connector CN A 1 AC 3 1B QCNCMA422DRE0 9 pin...

Страница 36: ...ion R 309BW 1 AH DOOR PARTS 5 1 FDORFA318WRT0 Door panel 1 BE 5 2 PSHEPA382WRE0 Sealer film 1 AH 5 3 GWAKPA458WRR0 Door frame 1 AY 5 4 HPNL A663WRR0 Door screen 1 AL 5 5 LSTPPA139WRF0 Latch head 1 AF 5 6 MSPRTA084WRE0 Latch spring 1 AB 5 7 PCUSUA481WRP0 Cushion 1 AB 5 8 PCUSUA452WRP0 Cushion 1 AB 5 9 XCPSD40P08000 Screw 4mm x 8mm 1 AA 5 10 XCPSD40P08WN2 Screw 4mm x 8mm 1 AC MISCELLANEOUS 6 1 FROLP...

Страница 37: ... 5 7 8 7 8 7 5 7 7 2 1 4 1 7 2 4 16 7 4 7 6 7 3 6 2 7 3 7 6 1 1 1 1 1 2 4 8 1 7 4 4 7 5 7 5 4 3 7 5 6 1 7 1 1 9 4 6 1 8 6 6 4 17 1 4 4 7 6 7 1 5 4 12 4 14 1 12 7 1 4 2 4 15 1 14 4 13 2 3 4 5 1 3 1 6 7 1 7 6 7 6 7 6 7 6 7 6 2 5 2 4 7 6 7 6 2 4 7 6 2 2 4 11 4 9 4 10 1 13 7 9 7 3 6 10 1 11 1 10 4 19 ...

Страница 38: ... B C D E F G H CONTROL PANEL PARTS DOOR PARTS MISCELLANEOUS 5 2 4 18 5 1 5 4 5 3 5 5 Actual wire harness may be different from illustration 6 4 6 5 6 3 HIGH VOLTAGE TRANSFORMER CAPACITOR 5 10 5 9 3 2 3 4 3 3 3 6 3 5 3 7 3 7 3 7 3 1F 3 1 3 3 1 5 7 5 6 5 8 ...

Страница 39: ...RE0 TOP PAD ASSEMBLY FPADBA341WRK0 PLASTIC BAG SSAKHA034WRE0 Not replaceable items PACKING CASE SPAKCD008WRE0 R 305BW SPAKCD009WRE0 R 309BW BOTTOM PAD ASSEMBLY FPADBA342WRK0 6 2 TURNTABLE TRAY 6 8 INSTRUCTION BOOK PRINTING MATTER 6 1 TURNTABLE SUPPORT TRAY PACK SPADFA397WRE0 INTO THE OVEN CAVITY CABINET COVER SPAKHA003WRE0 ...

Страница 40: ...BY SHARP CORPORATION ALL RIGHTS RESERVED No part of this publication may be repro duced storedinaretrievalsystems ortrans mitted in any form or by any means elec tronic mechanical photocopying record ing or otherwise without prior written per mission of the publisher ...

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