Sharp R-3A53, R-3A53B Service Manual

Download

Page 1

R-3A53 R-3A53B

SHARP SERVICE MANUAL

S7105R3A53PJZ

_1-1- --.II__ .----- -_ __ _ I. .^ II

MICROWAVE OVEN

MODELS

R-3A53

Photo R-3A53

R-3A53B ’

In interests of user-safety the oven should be restored to its original

condition and only manufacturer original spare parts must be used.

TABLE OF CONTENTS

Page

GENERAL

IMPORTANT

INFORMATION

......................................................................................................

CAUTION, MICROWAVE RADIATION,WARNING

......................................................................................

PRODUCT SPECIFICATIONS

.........................................................................................................................

APPEARANCE VIEW ........................................................................................................................................ 3

OPERATION SEQUENCE

.................................................................................................................................

FUNCTION OF IMPORTANT COMPONENTS

..............................................................................................

SERVICING

........................................................................................................................................................

TEST PROCEDURE

........................................................................................................................................ 10

TOUCH

CONTROL

ASSEMBLY

..................................................................................................................

COMPONENT

REPLACEMENT AND ADJUSTMENT PROCEDURE ..................................................... 25

MICROWAVE MEASUREMENT ...................................................................................................................

TEST DATA

AT A GLANCE .............................................................................. :-.

..........................................

WIRING

DIAGRAM

.......................................................................................................................................

PICTORIAL

DIAGRAM

..................................................................................................................................

CONTROL

PANEL CIRCUIT ......................................................................................................................... 39

PRINTED

WIRING DIAGRAM ..................................................................................................................... 40

PARTS LIST

.................................................................................................................................................... 41

PACKING AND ACCESSORIES

...................................................................................................................

SHARP CORPORATION

Page 2

SERVICE MANUAL

SHARI=

MICROWAVE OVEN

R-3A53/ R-3A53B

GENERAL IMPORTANT INFORMATION

This Manual has been prepared to provide Sharp Corp. Service engineers with Operation and Service Information.

It is recommended that service engineers carefully study the entire text of this manual, so they will be qualified to render satisfactory customer service.

___-

CAUTION

MICROWAVE RADIATION

Service engineers should not be exposed to the micro-

wave energy which may radiate from the magnetron or

other microwave generating devices if it is improperly

used or connected. All input and output microwave connections, waveguides, flanges and gaskets must be secured. Never operate the device without a microwave energy absorbing load attached. Never look into an open waveguide or antenna while the device is energized.

WARNING

Never operate the 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 not any other visible damage with the oven.

Servicing and repair work must be carried out only by trained service engineers,

All the parts marked ,,*‘I

on parts list are used at voltages

more than 250V.

SHARP CORPORATION

OSAKA, JAPAN

R-3A53 R-3A53B

/ .

PRODUCT SPECIFICATIONS

b, .

> S.,“. I “‘ .I,b,i’i~ 1x “/. *II ~

I^% V.&L

I ” *, ; I ‘: *.

9”

l,i

?-pap I

4’A” ,‘

_ ” “WXhI (_

Li”y.t I * &‘a* ‘

: j

OPERATING SEQUENCE 1;

,sj

‘>

* -.I

“-

7* l.s P’.

* *^ ,

” , jlll

t,-- i

? ,(, ,

I ,”

\ s

jx &&.l~~;@~” $2, ,; ‘&::p; ai- 1

_ *r_. .s”*z‘,+;*c, ?

I’ i,

6. FUNCTION OF IMPORTANT *‘-

COMPONENTS

“‘ 2‘

j:-

* ,

S”i ” *

_ I>

. 5

” bus*”

* _) f , .-;

‘,

III .-VC .“:

‘<r :

.< “?

,A* *$ 1 * Ti 1,;:“;

b *-

: & _ a*” * &a ,‘,:wt -* +,. -*,_ .a*.:4 $s. ,^6

‘ib

” Ps’

vs,a& A$“pq> <:,*, ;:, 2 ,z -‘*? * jr &

*j,7 1u

s a I

“WC XI ,*<ddA.+,s^ -

*s v&&*‘b

-i&s n d,v*

j a!

“;;r k;$

& $f

TROUBLESHOOTING CHART -“I

$3 j

* ,

^ ’

’ $$ * ‘> ;~

d,> Cc

’ - ~%+&&j

3 (”

: %*.,&’

“* I

& $&

TEST PROCEDURE

.‘

I k’

TOUCH CONTROL PANEL

* *

ASSEMBLY

;g+$

-- ‘*‘PB*h-

““,,‘&,“a

“.I

; -~<p&i‘r~~~,, “p”‘, ” s 8%

” “<f:“~&~~~~~~ ^

,:. *

j e’ 2; $@? I;$

I *

”

t , (‘” j$& g&g+) ,:* &- :‘.;*“’ -x

; ,-

‘-‘?,&>i “, (_ ;,

?$5 ^ f ( *. T, ”

” ” ,+~.:21&&

_ a “I 7” $‘$

t ;‘

* I A.?**$+

> 3

i”

CoMPoNENT I;;P;;;-EMEI;y \4:‘; “~

; B

AND ADJUSTMENT

PROCEDURE ,j&

* ” ( *, ,” * ? ? : ^C 1

,‘“4;:*”

S.%.

“j *” V” lb*< ,-: (>

I+”

<*_I ’

: ( ** ;“*

: ,,,$s”, :.* -.:k, ~

“! “^ ,< 5,

> “$

,’

* ‘:,,v j “: ‘i+i

5, :J4

_ “ii , i

<_I <( >

6 i

_ ;p

” : Q

a”

MICROWAVE MEASUREMENT ,

S,’

; f*

<I,”

” *

” s ” ,E , OX “?“i , ( y” Ins

“” ^^

.s._i) ir

*. ‘< _ ‘” ;

,, ~ -;&L”

tL ( *“““‘<&~

J” s , 4,12%>) * 1

: ?U 9*;; 9 6

% x

”

“, _, ^^“h^ -%L :

? s 9* ii.

* , >:* “::-: t&S ,~<~c,,*:&,,~; j

e &J--&y i *

/ $w..&<

+ =

’ : g y ‘Y

TEST DATA TAii A’ib

_ .z ’ ,”

w*>

TEST POINTS ON CONTROL

“~

UNIT

3, I

^ I

_ I

i” 0

; ,** i*’

r ,

SC!:,

~_” ‘:’

>?a>,’ .,* \:-,,

* (

tl-r s j

- 5’

“-- \<

I t

;f‘ ”

“;

WIRING DIAGRAM

“*

;

3” ,.

s *

L it: -r

L _ ‘l ( *v

,,” & a^ j_s ‘, iv ;& ?‘a g&“~~-“” xi , SI d

1 “~

2% ” ’

.:=f~ “$

“;iSL”.i * 4,

<^I ?bb\l

3 ! 2 * :*** ““1 (Y

\: >>

:“2. j A* ,- ,( 2; h-- ~ B *xi 3

i$s,.; ‘&,;’

^ c

.^.< >

’ 1”s ~

i ^V‘”

^_I

s t”

S*‘

- ”

:”

\<’ ,

PRINTED WIRING BOARD

- ”

“

, ’ I’ x ,,(

~;;*<:

‘y 3

1x_ “- , Y,

\. (

2, * “i

k”

-:‘:$g ;t, :- g&&, $ -=&.J\ “dg ;&@“+&

1 ,;s

d’k *i*‘,> $\): “p&&g&. L L s!*,- j I

‘c,,’ h: ;b ; * y 28,

SIS I

* “:

I-\ / < I

“, +,r

_I”>> /

-a *

PARTS LIST

Page 3

R -3A53 R-3A53B

PRODUCT SPECIFICATIONS

SPECIFICATION

ITEM

Power Requirements

! I

DESCRIPTION

1 240 Volts : Australia

230- 240 Volts : New Zealand

50 Hertz

Power Consumption

I_--------

Power Output

_____---

Outside Dimensions

Single phase, 3 wire earthed

---I

1 .I 6kW Awox. 5.0 A,

/ 700W (IEC-705-1988),‘6OOW (2 litre water load) 1 Operating frequency of 2450MHz

, Width 450mm 1 Height 285mm ) --Depth 340mm

Cooking Cavity Dimensions / Width 285 mm

i Height 185 mm

~-__-____----

i Depth 313mm

Turntable diameter

I 272mm

--____

Control Complement / Touch Control System

/ Clock! I:00 - 12:59 )

Timer (0 - 99 minutes 99 seconds )

, Microwave Power for Variable Cooking

Repetition Rate;

HIGH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Full power throughout the cooking time

MEDIUM HIGH ,.***...............*.*................

approx. 70% of Full Power

MEDIUM . . . . ..t...........................................

approx. 50% of Full Power

MEDIUM LOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . approx. 30% of Full Power

LOW

.,...*....*..*,..........,..........................,.....

approx. 10% of Full Power

AUTO COOK

--~ Set Weight

1 EASY REHEAT ’ EASY DEFROST 1 INSTANT COOK/START j MEMORY ’ AUTO START/CLOCK

VARIABLE COOKING CONTROL INSTANT ACTION (4 menu) NUMBER STOP/CLEAR

Approx. 14.0 kg

GENERAL INFORMATION

WARNING

THIS APPLIANCE MUST BE EARTHED

IMPORTANT

THE WIRES IN THIS MAINS LEAD ARE COLOURED IN ACCORDANCE WITH THE FOLLOWING CODE:

GREEN-AND-YELLOW : EARTH BLUE : NEUTRAL BROWN

: LIVE

Page 4

R-3A53 R -3A53B

APPEARANCE VIEW

0.6

1. Ventilation openings

8. Door button open

2. Oven lamp

9. Touch Control Panel

Waveguide cover 10.

Digital readout

4. Hinges 11. Access cover for oven lamp replacement

5. Safety door latches

12. Power supply cord

See through door 13.

Roller Stay

7. Hole of oven cavity

14.

Turntable

*Place the-roller stay on

the hole of oven cavity in the oven and seat the turntable on the roller stay.

Touch Control Panel

I 2 SERVE QUANTITY PAD

INSTANT ACTION PADS

Touch once to cook or reheat 4 popular menu.

AUTO COOK

mode.

AUTO COOK MEN& NUMBER PADS

clock time, weight or quantity of food, or to select the Auto Cook menus.

MEMORY

Touch to enter one frequently used cooking programme.

Touch to recall the memorized

programme.

VARIABLE COOKING CONTROL PADS

Touch to select microwave power setting. If not touched, HIGH is auto-

matically selected.

STOP/CLEAR PAD

Touch to erase gramming. Touch once to stop operation of oven during cooking; touch twice to cancel cooking programme.

I I

- INSTANT ACTION -

AUTO START/CLOCK PAD

Touch to set clock or Auto Start time.

To cook two serves, touch this pad prior to touching the INSTANT ACTION pad.

- 3 SERVE QUANTITY PAD

To cook three serves, touch this pad prior to touching the INSTANT ACTION pad.

4 SERVE QUANTITY PAD

To cook four serves, touch this pad prior to touching the INSTANT ACTION Pad.

- EASY DEFROST PAD

Touch to defrost meat by entering weight.

MORE( A 1, LESS( v 1 PADS

Touch to increase/decrease the time in one minute increments during cooking or to increase/decrease the time

whilst programming the Auto Cook, INSTANT ACTION or Easy Defrost modes.

-J

.INSTANT COOK/START PAD

Touch once to cook for 1 minute at HIGH or increase by 1 minute multiples each time

this pad is touched during cooking. Touch to start oven after setting programmes.

Page 5

I?-3A53 R-3A530

OPERATING SEQUENCE

OFF CONDITION

3. Closing the door activates all door interlock switches (1 st latch switch, 2nd latch switch and stop switch).

IMPORTANT

When the oven door is closed, the monitor switch contacts (COM -

NC) must be open.

When the microwave oven is plugged in a wall outlet.

Rated voltage (240 Volts : Australia, 230- 240 Volts : New Zealand) is supplied to the point Al + A3 in the

control unit.

Figure O-l on page 33 (For Australian) Figure O-3 on page 34 (For Ney Zealand)

The display flashes “88:88”. To set any programmes or set the clock, you must first touch the STOP/CLEAR key.

91 .

” appears in the display and the time counts

up every minute.

NOTE: When the oven door is opened, the oven

lamp comes on at this time.

MICROWAVE COOKING CONDITION

HIGH COOKING

Enter a desired cooking time with the touching NUMBER key and start the oven with touching START key.

Function sequence

Figure O-2 on page 33 (For Australian) Figure O-4 on page 34 (For New Zealand)

CONNECTED COMPONENTS

RELAY

Oven lamp, Fan motor, Turntable motor

-Power transformer

RYI RY2 -

1. Rated voltage is supplied to the primary winding of the power transformer. The voltage is converted to about 3.3 volts A.C. output on the filament winding and high voltage of approximately 2000 volts A.C. on the secondary winding.

2. The filament winding voltage (3.3 volts) heats the magnetron filament and the high voltage (2000

volts) is sent to the voltage doubling circuit, where

it is doubled to negative voltage of approximately

4000 volts D.C..

The 2450 MHz microwave energy produced in the

magnetron generates a wave length of 12.24 cm.

This energy is channeled through the waveguide

(transport channel) into the oven cavity, where the food is placed to be cooked. When the cooking time is up, a signal tone is heard and the relays RYI + RY2 go back to their home position.

The circuits to the oven lamp, power

transformer, fan motor and turntable motor are cut

off.

When the door is opened during a cook cycle, the switches come to the following condition.

CONDITION

DURING

DOOR OPEN

SWITCH

CONTACT

COOKING (NO COOKING)

1st latch switch

COM- NO

Closed

Open

Monitor switch

COM- NC

Open Closed

2nd latch switch

COM - NO

Closed Open

Stop switch

COM- NO Closed Open

The circuits to the power transformer, fan motor and turntable motor are cut off when the 1st latch switch, 2nd latch switch and stop switch are made open. The oven lamp remains on even if the oven door is opened after the cooking cycle has been interrupted, because the relay RYI stays closed. Shown

in the display is the remaining time. MONITOR SWITCH CIRCUIT

The monitor switch is mechanically controlled by

oven door, and monitors the operation of the 1 st and 2nd latch switches.

6-1

When the oven door is opened during or after the cycle of a cooking program, the 1 st latch and 2nd latch switches must open their contacts first. After that the contacts (COM - NC) of the monitor switch can be closed and then contacts of the stop switch can be opened.

6-2. When the oven door is closed, the contacts

(COM - NC) of the monitor switch must be opened and the contacts (COM - NO) of the stop switch must be closed first. After that the contacts of the 1st latch switch and 2nd latch switches are closed.

6-3. When the oven door is opened and the contacts

of the 1st and 2nd latch switches remain closed. The fuse M6.3A will blow, because the monitor switch is closed and a short circuit is caused.

Page 6

R -3A53 R-3A53B

MEDIUM HIGH, MEDIUM, MEDIUM LOW,

LOW COOKING

When the microwave oven is preset for variable cook-

ing power, 240 volts A.C. power is supplied to the power transformer intermittently within a 32-second time base through the relay contact which is coupled with the current-limiting relay, The following levels of microwave power are given.

SETTING

32 set ON

HIGH

24 set ON

8 set OFF

MEDIUM HIGH

m-1 Approx 70% = 490 Watts

18 sec. ON

14 set OFF

MEDIUM m-1 .Approx 50% = 350 Watts

12 sec. ON

20 set OFF

MEDIUM LOW

J-1 Approx 30% = 210 Watt:

6 set ON

26 set OFF

LOW

J] Approx 10% = 70 Watts

NOTE: The ON/OFF time ratio does not exactly corre-

spond to the percentage of microwave power, because approx. 2 seconds are needed for heating up the magnetron filament.

FUNCTION OF IMPORTANT COMPONENTS

DOOR OPEN MECHANISM

The door can be opened by pushing the door open

button on the control panel. When the door open

button is pushed, the switch lever is moved upward, operating the latch head.

The latch head is moved

upward, and released from the latch hook. Now, the door can be opened.

Door

Latch hook

Latch head

2nd latch switch

1 st latch switch

IST LATCH SWITCH SW1 2ND LATCH SWITCH SW2 STOP SWITCH SW4

1. When the oven door is closed, the contacts (COM

- NO) must be closed.

2. When the oven door is opened, the contacts (COM

- NO) must be opened.

MONITOR SWITCH SW3

1. When the oven door is closed, the contacts (COM- NC) must be opened.

2. When the oven door is opened, the contacts (COM- NC) must be closed.

3. If the oven door is opened and the contacts (COM - NO) of the 1 st and 2nd latch switches fail

to open, the fuse M6.3A blows simultaneously with closing the contacts (COM - NC) of the monitor switch.

CAUTION: BEFORE REPLACING A BLOWN FUSE F

M6.3A TEST THE IST AND 2ND LATCH

SWITCHES, MONITOR SWITCH AND

MONITOR RESISTOR FOR PROPER OPERATION. (REFER TO CHAPTER “TEST PROCEDURE”.)

MONITOR RESISTOR R 0.8 i2 20W

The monitor resistor prevents the fuse M6.3A bursting when the fuse M6.3A blows due to the operation of the monitor switch.

Switch lever

Figure D-l. Door Open Mechanism

Page 7

R -3A53 R-3A53B

ASYMMETRIC RECTIFIER

The asymmetric rectifier is a solid state device that prevents current flow in both directions. And it prevents the temperature rise of the power transformer by blowing the fuse M6.3A when the high voltage rectifier is shorted.

.+galG” VOLTAGE RECTIFIER

The rated peak reverse voltage of Dl of the asymmetric rectifier is 6 KV The rated peak reverse voltage of D2 of the asymmetric rectifier is 1.7 KV. Dl and D2 of the asymmetric rectifier or high voltage rectifier are shorted when the each peak reverse voltage goes beyond the each rated peak reverse voltage. (The process of blowing the fuse M6.3A.)

1. The high voltage rectifier is shorted by any causes when microwave cooking.

2. The peak reverse voltage of D2 of the rectifier goes beyond the rated peak reverse voltage 1.7 KV in the

voltage doubler circuit.

3. D2 of the rectifier is shorted.

4. The large electric currents flow through the high

voltage winding of the power transformer.

5. The large electric currents beyond 6.3A flow

through the primary widing of the power transformer.

6. The fuse M6.3A blows by the large electric currents.

7. The power supply to the all electrical parts is cut off.

FUSE F M6.3A

1. The fuse M6.3A blows when the contacts (COM

- NO) of the 1 st latch switch and 2nd latch switch remain closed with the oven door open and when the monitor switch closes.

2. The fuse M6.3A also blows when asymmetric rectifier, H.V. rectifier, H.V. wire harness, H.V. capacitor, magnetron or secondary winding of power transformer is shorted.

3. If the wire harness or electrical components are short-circuited, the fuse M6.3A blows to prevent an electric shock of fire hazard.

NOISE FILTER (FOR NEW ZEALAND)

The noise filter assembly prevents radio frequency interference that might flow back in the power circuit.

TEMPERATURE FUSE TFI 150°C (MG)

This fuse protects the magnetron against overheating.

If the temperature goes up higher than 150°C because the fan motor is interrupted, the air inlet duct is blocked or the ventilation openings are obstructed, the fuse blows and cuts off the power supplying to the power transformer. The defective fuse must be replaced with new rated one.

TEMPERATURE FUSE TF2 115°C

If the temperature of the temp. fuse goes up higher than 115°C because the ventilation openings are obstructed, the fuse blows and cut off the power supplying to the power transformer. The defective fuse must be replaced with new rated one.

TEMPERATURE FUSE TF3 150°C (OVEN)

The temperature fuse located on the top of the oven

cavity is designed to prevent damage to the oven if the

foods in the oven catch fire due to over heating

produced by unproper setting of cook time or failure

of timer motor.

Under normal operation, the temperature fuse remains

closed. However, when abnormally high temperatures are reached within the oven cavity, the temperature fuse will open at 1 50°C, causing the oven to shut down.

TURNTABLE MOTOR TTM

The turntable motor drives the roller stay to rotate the turntable.

FAN MOTOR FM

The fan motor drives a blade which draws external cool air. This cool air is directed through the air vanes sur-

rounding the magnetron and cools the magnetron. This air is channeled 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

Page 8

R-3A53 R-3A53B

SERVICING

WARNING TO SERVICE PERSONNEL

Microwave ovens contain circuitry capable of producing very high voltage and current, contact with any part of the high voltage circuit will result in electrocution.

REMEMBER TO CHECK 3D

1) Disconnect the supply.

2) Door opened, and wedged open.

3) Discharge high voltage capacitor.

REMEMBER TO CHECK 4R

1) Reconnect all leads removed from components during testing.

2) Replace the outer case (cabinet).

3) Reconnect the supply.

WARNING AGAtNST THE CHARGE OF THE

HIGH-VOLTAGE CAPACITOR

4) Run the oven. Check all functions.

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, of the connecting lead of the high-voltage rectifier)

against the chassis with the use of an insu-

lated screwdriver.

Sharp recommend

that

wherever

possible

fault-finding is carried out with the supply discon-

nected. It may in, some cases, be necessary to connect the supply after the outer case has been removed, in this event carry out $J checks and then disconnect the leads to the prrmary of the power

transformer. Ensure that these leads remain isolated from other components and the oven chassis. (Use

insulation tape if necessary.) When the testing is completed carry out 3D checks and reconnect the leads to the primary o-he power transformer.

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 microwave timer for two (2) minutes. Set the power level to

HIGH and push the START button. When the two minutes has elapsed (timer at zero) carefully check that the water is now hot. If the water remains cold carry out 30 checks 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 carried out.

TROUBLESHOOTING GUIDE

When troubleshooting the microwave oven, it is

helpfull to follow the Sequence of Operation in performing the checks. Many of the possible causes of trouble will require that a specific test be performed. These tests are given a procedure letter which will be found in the “Test Procedure”section.

IMPORTANT: If the oven becomes inoperative be-

cause of a blown fuse (M6.3A) in the

I-st latch switch - 2nd latch switch monitor switch - monitor resisitor circuit, check the 1 st latch switch, 2nd

latch switch, monitor switch and monitor resistor before replacing the fuse (M6.3A).

Page 9

R-3A53 R-3A53B

NOTE: “0” means direct cause and part. “A” means indirect cause and part.

CK: CHECK, RE: REPLACE

I--wcI)t-

aa00wn3aw

W W 7 LL

2 > $+J >EZ

i2sl

N D

iii

I 0 N

PROBLEM

Home fuse blows when power supply

cord is plugged into wall outlet. Fuse M6.3A blows when power supply

cord is plugged into wall outlet.

88 : 88 does not appear in display but

OFF CONDITION

power supply cord is plugged into wall

outlet.

Display does not operate properly when STOP/CLEAR pad is touched.

Oven lamp does not light at door opened. (Display appears.)

Oven does not start when START pad is touched. (Display appears.)

0 0

Oven lamp does not light. (Display

appears.) Fan motor does not operate. (Display

appears.)

Turntable motor assembly does not operate. (Display apears.)

Oven or any electrical parts does not stop. But cooking time is 0 or STOP/CLEAR pad is touched.

IIN 30NDITION

Oven seems to be operating but little or no heat is produced in oven load. (Micro-

000 00 0

wave power level is set at HIGH.) Oven does not seem to be operating

properly when MEDIUM HIGH, MEDIUM, MEDIUM LOW or LOW is set. (Oven

operates properly at HIGH and then the STOP/CLEAR pad is touched the oven stops. )

Oven goes into cook cycle but shuts down before end of cooking cycle.

* Oven stops as soon as when the START

pad is touched.

n/\nr\r\r\

Page 10

R-3A53 R-3A53B

CK: CHECK, RE: REPLACE

w Y ?L

c3 u-

u :: :: u ii 5 v v :: 5 :: -I 2

00 00 0 0 0 0

I I I

0 0 0

lo~o~0~0~ 10 0

0 0 00

000 ’ 00

0 0 /o/ 101 0

01 lOI IOI 0

-a 00 I

0 00

I I

OOA

0 0

Page 11

R-3A53 R-3A53B

TEST PROCEDURES

PROCEDURE

LETTER

COMPONENT TEST

MAGNETRON TEST

NEVER TOUCH ANY PART IN THE CIRCUIT WITH YOUR HAND OR AN INSULATED

TOOL WHILE THE OVEN IS IN OPERATION.

CARRY OUT 30 CHECKS

Isolate the magnetron from the high voltage circuit by removing all leads connected to the filament

terminal.

To test for an open circuit filament use an ohmmeter to make a continuity test between the

magnetron filament terminals, the meter should show a reading of less than 1 ohm.

To test for a short circuit filament to anode condition, connect ohmmeter between one of the filament terminals and the case of the magnetron (ground). This test should be indicated an infinite resistance. If a low or zero resistance reading is obtained then the magnetron should be re

laced,

MICROWAVE OUTPUT POWER (2 liter water load)

(R 82AOlU)

The following test procedure should be carried out with the microwave oven in a fully assembled condition (with outer case fitted). Microwave output power from the magnetron can be measured by way of substitution, i.e. it can be measured by using a water load how much it can be absorbed by the water load. To measure the microwave output power in the microwave oven, the relation of calorie and watt is used. When P(W) heating works for t(second), approximately P x t/4.2 calorie is generated.

On the other hand, if the temperature of the water with V(ml) rises AT

(“C) during this microwave heating period, the calorie of the water is V x AT.

I The formular is as follows;

P x t / 4.2 = V x AT P (W) = 4.2 x V x AT /t

Our condition for the water load is as follows:

Room

temperature . . . . . . . . . . . . . . . . . . . . . around 20°C

Power supply Voltage . . . . . . . . . . . . . Rated voltage

Water load . . . ...2000 ml

Initial temperature

. . . . . . . 1 O+ 1 “C

P=60xAT

Heating time . . . . . . 2min. 20 sec. /

Measuring method: A) Use two 1 litre Pyrex beakers with a diameter of approximately of 12cms. B) Place 1 litre of 10°C water in each beaker. C) Mark Tl on the one beaker and mark T2 on the other one. And stir the water and measure the

temperature of water the thermometer and note them. The graduation of the thermometer must

be scaled by 0.1 “C at minimum and an accurate mercury thermometer is recommended. D) Place the two beakers as touching each other in the centre of the cavity. E) Set the timer to 2minute and 20 seconds at 100% power (the time required to raise the water

temperature 10 degrees C.) F) The time must be measured with stopwatch or wristwatch. G) After 1 minute and 52 seconds, stop the oven by opening the door. H) Remove the two beakers from the oven and measure the temperature of the water by stiring the

water with the thermometer and noting the readings.

Example

Initial temperature

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tl = 10°C

= 11 “C

Temperature after 2min. 20 sec. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tl

= 20°C T2 = 21 “C I

Temperature difference Cold-Warm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1

= 10°C

AT2 = 10°C

Mean temperature rise AT AT = (AT1 +AT2) / 2 = (IOOC + IO'C) / 2 = 10°C

. . . . . . . . ;

Measured output power The equation is “P=

60 x

AT”

= . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

60 x 10°C

600 Watts

NOTE: The measured output power should be at least +I5 % of the rated output

power.

CAUTION: 1°C CORRESPONDS TO 60 WATTS.

REPEAT MEASUREMENT IF THE POWER IS INSUFFICIENT.

Page 12

R-3A53 R-3A53B

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

(Tl OC)

(T2 OC)

(T2 OCI

Heat up for 2min. 20 sec.

MICROWAVE OUTPUT POWER (IEC-705-1988)

(RD82A02U)

The following test procedure should be carried out with the microwave oven in a fully assembled

condition (outer case fitted). Microwave output power from the magnetron can be measured by way of IEC 705, i.e. it can be measured by using water load how much it can be absorbed by the water load. To measure the microwave output power in the microwave oven, the relation of cal-

orie and watt is used. When P(W) heating works for t(second), approximately P x t/4.1 87 calorie

is generated. On the other hand, if the temperature of the water with V(ml) rises AT (“C) during this microwave heating period, the calorie of the water is V x AT.

The formular is as follows;

Pxt/4.187=VxAT

P(W)=4.187xVxAT/t

Our condition for the water load is as follows:

Room temperature . . . . . . . . . . . . . . . . . . . . . around

20°C

Power supply Voltage . . . . . . . . . . . . . Rated voltage

Water load

. . . . . . . . 1000 g Initial temperature . . . . . . . 10+2”C Heating time . . . . . . . . . . . . . . . . 60 sec.

P=70xAT

Measuring condition:

I. Container

The water container must be a cylindrical borosilicate glass vessel having a maximum material thickness of 3 mm and an outside diameter of approximately 190 mm.

2. Temperature of the oven and vessel

The oven and the empty vessel are at ambient temperature prior to the start of the fest.

3. Temperature of the water

The initial temperature of the water is (10 + 2)“C.

4. Select the initial and final water temperature so that the maximum difference between the final

water temperature and the ambient temperature is 5°C.

5. Select stirring devices and measuring instruments in order to minimize addition or removal of

heat.

6. The graduation of the thermometer must be scaled by 0.1 “C at minimum and an accurate thermometer.

7. The water load must be (1000 + 5) g.

8. “t” is measured while the microwave generator is operating at full power. Magnetron filament heat-up time is not included.

NOTE: The operation time of the microwave oven is “t + 2” sec. 2 sec. is magnetron filament

heat-up time.

Page 13

R -3A53 R-3A53B

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

Measuring method:

1. Measure the initial temperature of the water before the water is added to the vessel (Example: The initial temperature Tl = 11 “C)

2. Add the 1 litre water to the vessel.

3. Place the load on the centre of the shelf.

4. Operate the microwave oven at HIGH for the temperature of the water rises by a va (10 & 2) “C.

5. Stir the water to equalize temperature throughout the vessel.

6. Measure the final water temperature. (Example: The final temperature T2 = 21 “C)

7. Caluculate the microwave power output p in watts from above formula.

ue A T of

Initial

temperature

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tl =

11 “C

Temperature

after

(60

+ 2) = 62

sec. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T2 =

21 “C

Temperature

difference Cold-Warm

AT1 =

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10°C

Measured output power

The equation

is “P=

70 x

AT”

P= 70 x 10°C = . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 700 Watts

JUDGMENT: The measured output power should be at least _+I5 % of the rated

output power.

CAUTION: 1°C CORRESPONDS TO 70 WATTS. REPEAT MEASUREMENT IF THE POWER IS

INSUFFICIENT.

T2”C

Heat up for 62 sec.

Page 14

R-3A53 R-3A53B

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

POWER TRANSFORMER TEST

WARNING: High voltages and large currents are present at the secondary wind-

r---- _

ing and filament winding of the power transformer. It is very dangerous to work

near this part when the oven is on.

NEVER make any voltage measurements of the

high-voltage circuits, including the magnetron filament.

CARRY OUT 3D CHECKS.

Disconnect the leads to the primary winding of the power transformer. Disconnect the filament and secondary winding connections from the rest of the HV circuitry. Using an ohmmeter, set on a low range, it is possible to check the continuity of all three windings. The following readings should be obtained :-

a. Primary winding ----------I .96 ohms approximately.

b. Secondary winding - - - - - - -97.2 ohms approximately.

c. Filament winding ---------less than 1 ohm.

If the reading obtained are not as stated above, then the power transformer is probably faulty and should be replaced.

CARRY OUT 4R CHECKS

Page 15

R-3A53 R-3A53B

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

HIGH VOLTAGE RECTIFIER ASSEMBLY TEST

HIGH VOLTAGE RECTIFIER TEST

CARRY OUT 3D CHECKS.

Isolate the high voltage rectifier assembly from the HV circuit. The high voltage rectifier can be

tested using an ohmmeter set to its highest range. Connect the ohmmeter across the terminal

B+C of the high voltage rectifier and note the reading obtained. Reverse the meter leads and note

this second reading. The normal resistance is infinity in one direction and more than 100 kfI in

the other direction.

CARRY OUT $fj CHECKS

ASYMMETRIC RECTIFIER TEST

CARRY OUT 3D CHECKS.

Isolate the high voltage rectifier assembly from the HV circuit. The asymmetric rectifier can be tested using an ohmmeter set to its highest range. Connect the ohmmeter across the terminals A+B of the asymmetric rectifier and note the reading obtained. Reverse the meter leads and note this second reading. If an open circuit is indicated in both directions then the asymmetric rectifier is good. If a asymmetric rectifier is shorted in either direction, then the the asymmetric rectifier is probably faultly and must be replaced with the high voltage rectifier. When the asymmetric rectifier is defective, check whether magnetron, high voltage rectifier, high voltage wire or filament winding of the power transformer is shorted.

CARRY OUT 4J CHECKS

NOTE: FOR MEASUREMENT OF THE RESISTANCE OF THE RECTIFIER,

OF THE MEASURING INSTRUMENT MUST HAVE A VOLTAGE AT

BECAUSE OTHERWISE AN INFINITE RESISTANCE MIGHT BE S DIRECTIONS.

THE BATTERIES

LEAST 6 VOLTS,

HOWN IN BOTH

D HIGH VOLTAGE CAPACITOR TEST

CARRY OUT 3D CHECKS.

A. Isolate the high voltage capacitor from the circuit. B. Continuity check must be carried out with measuring instrument which is set to the highest

resistance range.

C. A normal capacitor shows continuity for a short time (kick) and then a resistance of about

10 MQ after it has been charged. D. A short-circuited capacitor shows continuity all the time. E. An open capacitor constantly shows a resistance about 10 Mf2 because of its internal 10

MI2 resistance. F. When the internal wire is opened in the high voltage capacitor, the capacitor shows an in-

finite resistance

G. The resistance across all the terminals and the chassis must be infinity when the capacitor

is normal.

If incorrect readings are obtained, the high voltage capacitor must be replaced.

CARRY OUT 4FJ CHECKS

Page 16

R-3A53 R-3A53B

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

SWITCH TEST

CARRY OUT 3D CHECKS.

Isolate the switch to be tested and using an ohmmeter check between the terminals as described in the following table.

Table: Terminal Connection of Switch

1 Plunger Operational ~~ C6M to NO

COM to NC 1

COM; Common terminal

S.C.; Short circuit NO; Normally open terminal O.C.; Open circuit NC; Normally closed terminal

If incorrect readings are obtained, make the necessary switch adjustment or replace the switch.

CARRY OUT 4R CHECKS.

TEMPERATURE FUSE TEST

CARRY OUT 3D CHECKS

Disconnect the leads from the terminals of the temp. fuse. Then using an ohmmeter, make a continuity test across the two terminals as described in the table below.

CARRY OUT 4R CHECKS

Table: Temperature Fuse or Thermal Cut-out Test

Temperature of Temperature of

Indication of

“ON” condition “OFF” condition

ohmmeter

Parts Name

(closed circuit). (open circuit).

(When room

(“Cl (“C)

temperature is

approx. 20°C.)

Temp. fuse 1 50°C

This is not resetable Above 1 50°C Closed circuit

(MG)

type.

Temp. fuse

This is not resetable Above 115°C Closed circuit.

115Oc

type

Temp. fuse 1 50°C

This is not resetable Above 1 50°C Closed circuit

(OVEN)

type.

If incorrect readings are obtained, replace the temp. fuse or thermal cut-out.

An open circuit temperature fuse 150°C indicates that the magnetron has overheated, this may be due to resistricted ventilation, cooling fan failure or a fault condition within the magnetron or HV circuit.

An open circuit temp. fuse 150°C (OVEN) indicates that the oven cavity has over heated, this may be due to no load operation or catching fire of foods in the oven cavity.

An open circuit temp. fuse 115°C indicates that the inner parts of the oven have overheated, this may be due to resisted ventilation.

An open circuit temperature controller indicators that the steam duct reaches high temperature.

Page 17

R-3A53 R-3A530

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

G MONITOR RESISTOR TEST

CARRY OUT 30 CHECKS. Disconnect the leads from the monitor resistor or surge resistor.

Using an ohmmeter and set on a low range. Check between the terminals of the monitor resistor or surge resistor as described in the following table.

Table: Resistance

Resistor

Resistance

-1

Monitor resistor

Approx. O.Sn

If incorrect readings are obtained, replace the monitor resistor or surge resistor

CARRY OUT 4R CHECKS.

MOTOR WINDING TEST

CARRY OUT 3D CHECKS

Disconnect the leads from the motor. Using an ohmmeter, check the resistance between the two terminals as described in the table below.

Table: Resistance of Motor

otors

Resistance

1 F

an motor 1 Approximatelv 252 ohms

1 Turntable motor

1 Approximately 13.75 kohms

If incorrect readings are obtained, replace the motor. (Also refer to test procedure I)

CARRY OUT 4R CHECKS

LIVE TEST FOR MOTOR WINDINGS

CAUTION: The following procedure requires the oven to be connected to the supply

and should only be used if the relevant “cold” checks for the motor under test are inconclusive.

1. CARRY OUT 3D CHECKS

2. Disconnect the leads from the primary of the power transformer. Make sure that the leads remain isolated from other oven components and chassis. (Use insulation tape if necessary.)

3. Connect a voltmeter, set to 250V AC, across the motor terminals. (Refer to the relevant motor test procedure or pictorial diagram for the correct terminal numbers.)

4. Arrange the meter in a position where it can be read during the test. (Do not touch the meter, meter leads or oven circuitry while the oven is active.)

5. Close the oven door.

6. Set the reievant timer for about three (3) minutes, set the power level to HIGH and push the START button.

7. Note the reading on the meter and carefully observe the motor under test to see if it is turning.

8. CARRY OUT 3D CHECKS

9. Remove test meter leads. 1 O.Reconnect the leads to the primary of the power transformer.

If a reading of 240 volts AC was obtained (step 7) but the motor was not turning then it is faulty and should be replaced. If the meter indicated that no supply was present then the wiring to the motor should be checked for continuity.

Page 18

R-3A53 R-3A53B

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

NOISE FILTER TEST

WHT

CARRY OUT 3D CHECKS

Disconnect the leads from the terminals

Rl 10 M ohm f 20%

of the noise filter.

Using an ohmmeter, check between the

terminals as described in the following

L iminl

cxtzo%

l.OmH 0 06&F

R2 1 5 M ohm f 20%

CvtZo?d

0 0022,1F

table.

MEASURING POINTS

------I-

INDICATION OF OHMMETER

Between N and L

Approximately 1.5M0

Between terminal N and WHITE

Short circuit

Between terminal L and RED

! Short circuit

If incorrect readings are obtained, replace the noise filter unit. CARRY OUT 4R CHECKS

BLOWN FUSE F M6.3A

CARRY OUT 3D CHECKS

1. If the fuse M6.3A is blown, there could be a shorts or ground in electrical parts or wire harness. Check them and replace the defective parts or repair the wire harness.

2. If the fuse M6.3A is blown when the door is opened, check the 1st latch switch, 2nd latch switch, monitor switch and monitor resistor.

If the fuse M6.3A is blown by incorrect door switching replace the defective switch(s) and

the fuse M6.3A.

3. If the fuse M6.3A is blown, there could be a short in the asymmetric rectier or there could be

a ground in wire harness.

A short in the asymmetric rectifier may have occured due to short or ground in H.V. rectifier, magnetron, power transformer or H.V. wire. Check them and replace the defective parts or repair the wire harness.

CARRY OUT 4R CHECKS

CAUTION: Only replace fuse with the correct value replacement.

Page 19

R-3A53 R-3A53B

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER COMPONENT TEST

TOUCH CONTROL PANEL ASSEMBLY TEST

The touch control panel consists of circuits including semiconductors such as LSI, I&, etc. Therefore, unlike conventional microwave ovens, proper maintenance cannot be performed with only a voltmeter and ohmmeter. vided into two units, Control

In this service manual, the touch control panel assembly is di-

Unit and Key Unit, and troubleshooting by unit replacement is de-

scribed according to the symptoms indicated.

1. Key Unit. The following symptoms indicate a defective key unit. Replace the key unit. a) When touching the pads, a certain pad produces no signal at all. b) When touching a number pad, two figures or more are displayed.

c) When touching-the pads, sometimes a pad produces no signal.

2. Control Unit The following symptoms indicate a defective control unit. Replace the control unit. 2-l In connection with pads. a) When touching the pads, a certain group of pads do not produce a signal. b) When touching the pads, no pads produce a signal. 2-2 In connection with indicators a) At a certain digit, all or some segments do not light up. b) At a certain digit, brightness is low. c) Only one indicator does not light. d) The corresponding segments of all digits do not light up; or they continue to light up. e) Wrong figure appears.

f) A certain group of indicators do not light up.

g) The figure of all digits flicker. 2-3 Other possible troubles caused by defective control unit.

Buzzer does not sound or continues to sound.

b) Clock does not operate properly.

c) Cooking is not possible. d) Proper temperature measurement is not obtained.

M PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING

BOARD (PWB) IS OPEN.

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. If the foil pattern is open, follow the troubleshooting guide given below for repair.

Problem: POWER ON, indicator does not light up.

STEPS OCCURANCE CAUSE OR CORRECTION

1 ‘The rated AC voltage is not present at POWER ter- Check supply voltage and oven power cord. Please

minal of CPU connector (CN-A)

use term “Low voltage transformer” when refering to

transformer Tl

2 The rated AC voltage is present at primary side of low Low voltage transformer or secondary circuit defec-

voltage transformer. tive. Check and repair.

3 Only pattern at “a” is broken.

‘Insert jumper wire J3 and solder.

4 Pattern at “a” and “b” are broken. *Insert the coil RCILF2003YAZZ between “c”

i--

“d”.

NOTE:’ At the time of these repairs, make a visual in-

spection of the varistor for burning damage and examine the transformer with tester for the presence of layer short-circuit (check primary coil resistance). If any abnormal condition is detected, replace

the defective parts.

D82

Page 20

R-3A53 R-3A53B

TOUCH CONTROL PANEL ASSEMBLY

OUTLINE OF TOUCH CONTROL PANEL

The touch control section consists of the following units as shown in the touch control panel circuit.

(1) Key Unit (2) Control Unit

The principal functions of these units and the signals communicated among them are explained below.

Key Unit

The key unit is composed of a matrix, signals generated

in the LSI are sent to the key unit through SO-S6. When a key pad is touched, a signal is completed through the key unit and passed back to the LSI through K4-K7 to perform the function that was requested.

Control Unit

Control unit consists of LSI, power source circuit, synchronizing signal circuit, ACL circuit, buzzer circuit and indicator circuit.

1) LSI

This LSI controls the key strobe signal, relay driving signal for oven function and indicator signal.

2) Power Source Circuit

This circuit generates voltage necessary in the control unit.

Svmbol Voltaae Aoolication VDD

-12v

LSI (ICI ), ACL circuit VREF VP

al&v LSI (ICI)

Fluorescent display tube : Grid

and anode voltage VFI

3V P-P Fib”,“ent of fluorescent display

VF2 (VFI to VF2 voltage)

3) Synchronizing Signal Circuit

The power source synchronizing signal is available

in order to compose a basic standard time in the

clock circuit.

It accompanies a very small error because it works

on commercial frequency.

ACL Circuit

A circuit to generate a signal which resets the LSI to the initial state when power is supplied.

Buzzer Circuit

The buzzer is responsive to signals from the LSI to emit noticing sounds (key touch sound and completion sound).

Door Sensing Switch

A switch to “tell” the LSI if the door is open or closed.

Relay Circuit

To drive the magnetron, fan motor, turntable motor and light the oven lamp.

Indicator Circuit

Indicator element is a Fluorescent Display.

Basically, a Fluorescent Display is a triode having a cathode, a grid and an anode. Usually, the cathode of a Fluorescent Display is directly heated and the filament serves as cathode. The Fluorescent Display has 6-digits, 13-segments are used for displaying figures.

Page 21

R -3A53

R-3A53B

DESCRIPTION OF LSI

LSl(lZA377DR)

The I/O signals of the LSl(lZA377DR) are detailed in the following table.

PIN NO. / 1

Signal to sound buzzer.

SIGNAL / T

I/O

1 OUT

A: Key touch sound (0.12 sec.).

B: Completion sound (2.4 sec.).

PIN NO. / 2 1 SIGNAL /

VDD

I/O

_-_---_

Power source voltage: -12V

VDD voltage of power source circuit input.

PIN NO. / 3 SIGNAL

/ VREF

I/O

Reference voltage input terminal.

A reference voltage applied to the A/D converter in the LSI. The reference voltage is generally maintained at -6.15V

PIN NO.

j 4

1 SIGNAL 1 VP

I/O

___-

/ IN

Anode (segment) of Fluorescent Displav illumination voltage: -26V

Vp voltage of power source circuit input.

PIN NO. / 5 SIGNAL / INT

I/O

/ IN

Signal svnchronized with commercial source frequencv(50Hz).

This is the basic timing for time processing of LSI.

PIN NO. 1 6 1 SIGNAL 1 CNVSS

Power source voltage input terminal.

Connected to GND.

I/O

1 IN

PIN NO. / 7-10 1 SIGNAL / FO-F3

I/O

1 OUT

Segment data sionals.

Refer to the touch control panel circuit for the relationship between signals and indicators.

Normally, one pulse is output in every synchronized signal period, and input to the anode of the fluorescent display.

PIN NO. 11

1 SIGNAL / SO

l/O

1 OUT

Segment data signal.

Signal similar to FO.

Kev strobe siqnal.

Signal applied to touch-key section. A pulse signal is input to K4-K7 terminal while one of D-8 line keys on key matrix is touched, Terminal not used.

PIN NO. j 12

Segment data signal.

Signal similar to FO.

Key strobe signal.

SIGNAL / Sl

I/O

) OUT

Signal applied to touch-key section. A pulse signal is input to K4-K7 terminal while one of D-7 line keys on key matrix is touched.

Page 22

R-3A53 R-3A53B

PIN NO. j 13

Segment data signal.

Signal similar to FO.

Key strobe sianal.

SIGNAL j S2

I/O ; OUT

~-____--

--- ---- ..-- - _____ _

Signal applied to touch-key section. A pulse signal is input to K4-K7 terminal while one of D-6 line keys on key matrix is touched.

PIN NO. 1 14

SIGNAL / S3

I/O

’ OUT

----~

Segment data signal.

Signal similar to FO.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to K4-K7 terminal while one of D-5 line keys on key matrix is touched.

G-NO. 1 15

Segment data signal.

Signal similar to FO.

Key strobe signal.

1 SIGNAL i S4

-I-

I/O

; OUT

___---__- -____ ----

Signal applied to touch-key section. A pulse signal is input to K4-K7 terminal while one of D-4 line keys on key matrix is touched.

PIN NO. / 16

1 SIGNAL j S5

--L-!E-OUT

___ .

Segment data signal.

Signal similar to FO.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to K4-K7 terminal while one of D-3 line keys on key matrix is touched.

PIN NO. 17 1 SIGNAL LS6

. __ _-___-_-- _

I/O

1 OUT

Segment data signal.

Signal similar to FO.

Key strobe sianal.

Signal applied to touch-key section. A pulse signal is input to K4-K7 terminal while one of D-2 line keys on key matrix is touched.

PIN NO. / 18

1 SIGNAL j S7

l/O

: OUT

-__-__-___

____--

Seqment data signal.

Signal similar to FO.

PIN NO. 1 19

1 SIGNAL 1 XOUT

Internal clock oscillation frequency control output.

Output to control oscillation input of XIN.

I/O

i OUT

----A.--

___I___ -..- ___.-

PIN NO. ‘/ 20

1 SIGNAL 1 XIN

I I/O

i IN

Internal clock oscillation frequency input settins

The internal clock frequency is set by inserting the ceramic filter oscillation circuit with respect to XOUT terminal.

PIN NO. 1 21

1 SIGNAL / VSS

Power source voltane input terminal.

Connected to GND.

I/O

) IN

--- ___--

Page 23

R-3A53 R-3A530

PIN NO.

/ 22-24 1 SIGNAL j Dll-D9

I/O

/ OUT

Diqit selection siqnal.

Refer to the touch control panel circuit about the relation between signals and digits.

Normally, one pulse is output in every synchronized signal period, and input to the grid of the fluorescent display.

PIN NO. I 25-27

Qiqit selection signal.

Signal similar to Dll .

1 SIGNAL / 08-06

I/O

1 OUT

PIN NO. 28

Segment data siqnal.

Signal similar to FO.

1 SIGNAL / D5

I/O

j OUT

PIN NO.

29-31

Terminal not used.

1 SIGNAL /

D4-D2

I/O

/ OUT

PIN NO. i 32

1 SIGNAL 1 Dl

Maqnetron Hiqh-voltaqe circuit drivinq siqnal.

To turn on and off the cook relay.

I/O

1 OUT

In high operation, the signals holds “H” level during microwave cooking and “L” level while not cooking. In other

cooking modes (MED. HIGH, MED., MED. LOW, LOW) the signal turns to “H” level and “L” level in repetition according to the power level.

PIN NO. 1 33

1 SIGNAL / DO

I/O

1 OUT

Oven lamp, turntable motor and coolinq fan motor drivinq signal. (Square Waveform: 50Hz)

To turn on and off the control relay. The pulse signal (50Hz) is delivered to the control relay driving circuit and cook relay control circuit.

PIN NO. 1 34

Auto clear terminal.

1 SIGNAL 1

RESET

l/O

/ IN

Signal is input to reset the LSI to the initial state when power is supplied. Temporarily set to “H” level the moment power is supplied, at this time the LSI is set. Thereafter set at “L” level.

PIN NO. 35

1 SIGNAL 1 K7

I/O

Siqnal cominq from touch key.

When either one of D-9 line keys on key matrix is touched, a correspondin signal out of SO-S6 will be input into

K7. When no key is touched, the signal is held at “L” level.

PIN NO. / 36 1 SIGNAL j K6

1 ILO / IN

Signal cominq from touch key.

When either one of D-10 line keys on key matrix is touched, a corresponding signal will be input into K6.

PIN NO. 1 37

1 SIGNAL 1 K5

I/O

/ IN

Siqnal cominq from touch key.

When either one of D-l 1 line keys on key matrix is touched, a corresponding signal will be input into K5.

PIN NO. / 38 1 SIGNAL / K4

I/O

/ IN

Signal cominq from touch kev.

When either one of D-12 line keys on key matrix is touched, a corresponding signal will be input into K4.

Page 24

R-3A53 R-3A53B

PIN NO, 1 39

1 SIGNAL j K3

I/O

/ 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.

PIN NO. 1 40

1 SIGNAL j K2

l/O

/ IN

Input sianal which communicates the door open/close information to LSI.

Door closed; “H” level signal. Door opened;

“L” level signal.

PIN NO. 1 41

Terminal not used.

1 SIGNAL j Kl

I/O

PIN NO. 1 42

1 SIGNAL j KO

--Terminal to change cooking constant.

I/O

Page 25

R-3A53 R-3A53B

SERVICING

I. Precautions for Handing Electronic

Components

This unit uses PMOS LSI in the integral part of the circuits. When handing these parts, the following precautions should be strictly followed.

PMOS LSI have extremely high impedance at its input and output terminals. For this reason, it is easily influenced by the surrounding high voltage power source, static electricity charged in clothes, etc,and sometimes it is not fully protected by the built-in protection circuit. In order to protect PMOS LSI.

1) When storing and transporting, thoroughly

wrap them in aluminum foil. Also wrap PW boards containing them in aluminium foil.

2) When soldering, ground the technician as

shown in the figure and use grounded soldering iron and work table.

. .

approx. 1 MR

IRYN

2. Shapes of Electronic Components

ECB

Trakistor DTA 1 l4ES DTC 114ES DTD 143ES

3. Servicing of Touch Control Panel

We describe the procedures to permit servicing the touch control panel of the microwave oven and the cautions you must consider when doing so. To carry the servicing, power supply to the touch control panel is available either from the power line of the oven proper itself of from an external power source.

(1) Servicing the touch control panel with

power supply from the oven proper:

CAUTION: THE HIGH VOLTAGE TRANSFORMER OF THE MICROWAVE OVEN IS STILL ALIVE TO GIVE YOU DANGER DURING SER-

VICING.

Therefore, when checking the performance of the touch control panel,put the outer cabinet on the oven proper to keep from touching the

high voltage transformer, or unplug the primary terminal (connector) of the high voltage transformer to turn it off; and the end of such connector shall be insulated with an insulating tape. After servicing, be sure to replace the leads to their original locations.

A. On some models, the power supply cord be-

tween the touch control panel and the oven

proper is so short that they can’t be separated

from each other.

For those models, therefore, check and repair all the controls (with the sensor-related ones included) of the touch control panel while keeping it in contact with the oven proper.

B. On some models, on the other hand, the power

supply cord between the touch control panel and the oven proper is so long that they may be separated from each other. For those mod-

els, therefore, it is allowed to check and repair the controls of the touch control panel while keeping it apart from the oven proper;in this case you must short both ends of the stop switch (on PWB) of the touch control panel with a jumper, which brings about an operational state that is equivalent to that with the oven door being closed. As to the sensor-related controls of the touch

control panel, their checking is allowed if the dummy resistor(s) whose resistance is equal to that of,those controls is used.

(2) Servicing the touch control panel with

power supply from an external power source:

Disconnect the touch control panel completely from the oven proper,and short both ends of the stop switch (on PWB) of the touch control panel,which brings about an operational state that is equivalent with the oven door being closed. And connect an external power source

to the power input terminal of the touch control

panel, and then it is allowed to check and repair

the controls of the touch control panel;as in the

case of (1) - B above, it is here also possible to

check the sensor-related controls of the touch control panel by using the dummy resistor(s).

4. Servicing Tools

Tools required when servicing the touch control panel assembly.

1) Soldering iron: 30W (To prevent leaking current, it is recommended to use a soldering iron with a grounding terminal.)

2) Oscilloscope:

Single beam, frequency range:

DC - IOMHz type or more ad-

vanced model.

3) Others:

Hand tools

5. Other Precautions

I) Before turning on the power source of the

control unit, remove the aluminum foil applied

for preventing static electricity.

2) Connect the connectors of the indicator and key units to the control unit taking care that the lead wires are not twisted.

3) After aluminum foil is removed, take extra care that abnormal voltage due to static electricity etc. is not applied to the input or output terminals

4) Attach connectors, electrolytic capacitors, etc. to PWB, taking care that all connections are

tight.

5) Be sure to use specified components where high precision is required.

Page 26

R-3A53 R-3A530

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

WARNING: Avoid possible exposure to microwave energy. Please follow the instructions below

before operating the oven.

1. CARRY OUT 3D CHECKS.

I. Door does not close firmly.

2. Make sure that a definite “click” can be heard when

2. Door hinge, support or latch hook is damaged.

the microwave oven door is unlatched. (Hold the

3. The door gasket or seal is damaged.

door in a closed position with one hand, then push

4. The door is bent or warped.

the door open button with the other, this causes the

5. There are defective parts in the door interlock sys-

latch heads to rise, it is then possible to hear a

tern.

“click” as the door switches operate.)

6. There are defective parts in the microwave generat-

3. Visually check the door and cavity face plate for

ing and transmission assembly.

damage (dents, cracks, signs of arcing etc.).

7. There is visible damage to the oven.

Carry out any remedial work that is necessary before operating the oven.

Do not operate the oven:

1. Without the RF gasket (Magnetron).

2. If the wave guide or oven cavity are not intact.

Do not operate the oven if any of the following con-

ditions exist;

3. If the door is not closed.

4. If the outer case (cabinet) is not fitted.

Please refer to ‘OVEN PARTS, CABINET PARTS, DOOR PARTS’, when carrying out any of the following removal

procedures:

OUTER CASE REMOVAL

To remove the outer case, proceed as follows.

1. Disconnect oven from power supply.

2. Open the oven door and wedge it open.

3. Remove the screws from rear and along the side edge of case.

Note: For Australian model

Remove the two (2) LHSTIX screws from the rear of the outer case cabinet, using special driver LHSTIX (LR-4).

LHSilX SCREW DRIVER (SIZE LH-4)

LHiTlX SCREW

Note: When securing or loosening the LHSTIX screw,

LHSTIX (LR-4) TYPE screw driver should be used.

4. Slide the entire case back about 1 inch (3cm) to free it from retaining clips on the cavity face plate.

5. Lift the entire case from the oven.

6. Discharge the H.V. capacitor before carring out any

further work.

7. Do not operate the oven with the outer case removed.

N.B.; Step I,2 and 6 form the basis of the 3D checks.

CAUTION: DISCHARGE

HIGH VO LTAG E

CAPACITOR BEFORE TOUCHING ANY

OVEN COMPONENTS OR WIRING.

Page 27

R-3A53 R-3A53B

HIGH VOLTAGE COMPONENTS REMOVAL

(HIGH VOLTAGE CAPACITOR AND HIGH VOLTAGE RECTIFIER ASSEMBLY)

1. CARRY OUT 3iJ CHECKS.

2. Release the H.V.C. cover from the bottom plate as shown in Figure C-l.

8. Remove the single (1) screw holding the earth side terminal of the high voltage rectifier assembly to the capacitor holder.

3. Slide the tabs of the H.V.C. cover to the direction the arrow shows with releasing the tab A from the back plate.

4. Remove the H.V.C. cover from the back plate of the oven cavity.

5. Disconnect the H.V. wire A with the filament lead of the power transformer from the high voltage capacitor.

6. Disconnect the H.V. wire of the H.V. rectifier as-

sembly from the power transformer. p-

7. Remove the single (1) screw holding the capacitor

9. Disconnect the H.V. rectifier assembly from the high

voltage capacitor.

1 O.Now, high voltage capacitor and H.V. rectifier are

free.

CAUTION: WHEN REPLACING HIGH VOLTAGE

RECTIFIER ASSEMBLY, ENSURE THAT

THE CATHODE (EARTH) CONNECTION

SECURELY FI)(ED TO

THE

CAPACITOR

HOLDER

WITH AN

EARTHING SCREW.

holder to the bottom plate.

Bottom plate

Tab A

Figure C-l. H.V.C Cover Removal

High Voltage wire A

ower transformer

Figure C-Z. Wiring of H.V. Wire A

CAUTION: When replacing high voltage compo-

nents, wire the H.V. wire A as shown in

Figure C-2.

POWER TRANSFORMER .REMOVAL

1. CARRY OUT3JCHECKS

2. Disconnect the main harness from the power transformer

3. Disconnect the H.V. wire of the H.V. rectifier as-

sembly from the power transformer.

4. Disconnect the filament lead of the power transformer from the H.V. wire A.

5. Disconnect the filament lead of the power transformer from the magnetron.

6. Remove the three (3) screws holding the power transformer to the bottom plate.

7. Remove the trans cushion from the power transformer.

8. Remove the power transformer from the bottom plate. Now, it is free.

Page 28

R -3A53 R-3A53B

MAGNETRON REMOVAL

I, CARRY OUT 3D CHECKS

4. Remove the magnetron from the waveguide with

2. Disconnect leads from magnetron.

3. Carefully remove four (4) screws holding magnetron to waveguide, when removing the screws hold the magnetron to prevent it from fall-

ing.

care so the magnetron antenna is not hit by any metal object around the antenna

CAUTION: WHEN REPLACING THE MAGNETRON,

BE SURE THE R.F. GASKET IS IN PLACE

AND THE

MAGNETRON MOUNTING SCREWS ARE TIGHTENED SECURELY.

CONTROL PANEL REPLACEMENT

Removal

1. CARRY OUT 3D CHECKS.

2. Disconnect the leads from the control panel.

3. Raise the tab of the oven cavity.

4. Lift up the control panel assembly.

5. Release the control panel from the oven cavity.

6. Now, the control panel assembly is free.

Installation

1. Put the tabs of the control panel into the holes of the oven cavity.

2. Push down the control panel.

3. Fold the tab of the oven cavity as shown in Figure C-4 (a).

Note: If the tab of the oven cavity has been broken,

to hold the control panel to the oven cavity use the single (1) screw (XOTSD40P12000) as shown in Figure C-4 (b).

Control panel Control panel

Tab of the

oven cavity

ity

Note: If the tab of the oven cavity has been broken,

to hold the control panel to the oven cavity use the single (1) screw (XOTSD40P12000) as shown in Figure C-4 (b).

Figure C-3. Control Panel Removal

Control panel

Screw : XOTSD40P 12000

Figure C-4 (a). Control Panel Installation

Figure C-4 (b). Control Panel Installation

FAN MOTOR ASSEMBLY REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect the wire leads from the fan motor.

3. Remove the two(2) screws holding the fan motor

to the back plate of the oven cavity.

4. Now, the fan motor is free.

Page 29

R-3A53 R-3A53B

TURNTABLE MOTOR REPLACEMENT

Removal

Re-install

1. Disconnect the oven from the power supply.

2. Remove the turntable and roller stay from the oven cavity.

3. Turn the oven over.

4. Cut the four (4) bridges holding the turntable motor cover to the bottom plate with the cutting pliers as shown in Figure C-5 (a).

CAUTION: DO NOT DROP THE TURNTABLE

MOTOR COVER INTO THE OVEN AF-

TER CUTTING THE BRIDGES. BE-

CAUSE IT WILL DAMAGE THE WIRE LEADS OF THE MOTOR. --AND IT IS DIFFICULT TO REMOVE IT OUT OF

THE OVEN.

Remove the any sharp edges on the turntable motor cover and the bottom plate with the cutting pliers. Remove the single (1) screw and the single (1) washer on the bottom plate as shown in Figure C-5 (a).

Re-install the O-ring. Appply the grease (Shinetsu silicone grease G-420 of Sinetsu Chemical Co. Ltd. or Toray Silicone grease SH-14 of Toray Silicone Co.,

Ltd.). to the O-ring and the roots of the turntable motor shaft as shown in Figure C-6.

Re-install the single (1) washer to the turntable motor. Re-install the turntable motor with the O-ring and washer to the oven cavity with the single (1) screw. Re-connect the wire leads to the turntable mo-

tor.

Remove the turntable

tom plate.

Disconnect the wire

motor.

Remove the single

motor cover from the bot-

leads from the turntable

(1) screw holding the turntable motor to the oven cavity. Remove the turntable motor from the oven cavity. Remove the O-ring and washer from the turntable motor.

lO.Now, the turntable motor is free.

Turntable motor cover

Cuttrng

Bridges / Bridges

Bottom

pliers

Figure C-5 (a). Turntable Motor Cover Removal

Turn

Roots of turntable motor shaft

table motor

Insert the tab of the turntable motor cover into the hole of the bottom plate as shown in Figure C-5-(b).

Re-install the turntable motor cover to the bottom plate with the screw and the washer which are removed at the above step 2 as shown in Figure C-5 (b).

Screw: XFPSD40P08000

asher: XWSSD40-10000

Bottom plate

Figure C-5 (b). Turntable Motor Cover

Re-install

Washer

Apply the grease here

Figure C-6. Washer and O-ring Installation and Grease Applying

Page 30

R -3A53 R-3A53B

OVEN LAMP SOCKET REMOVAL

1. CARRY OUT 30 CHECKS.

2. Lift up the oven lamp socket.

3. Pull the wire leads from the oven lamp socket by pushing the terminal hole of the oven lamp socket with the flat type small screw driver.

4. Now, the oven lamp socket is free.

CAUTION: When replacing the oven lamp socket, re-

place it so that the side where the black

dot is put faces upward.

Own lamp sodcot

Twminal

Flat type small

Torminai holo

Figure C-7. Oven Lamp Socket

POWER SUPPLY CORD REPLACEMENT

(FOR AUSTRALIAN MODEL)

Removal

1. CARRY OUT 3D CHECKS.

2. Disconnect the brown wire of the power supply cord from the fuse holder.

3. Remove the connector CE-230 by cutting the con-

nected wire leads to it.

4. Remove the single (1) screw holding the green/yellow wire of the power supply cord to the oven cavity.

5. Remove the single (1) screw holding the cord anchorage to the oven cavity.

6. Remove the power supply cord from the oven.

Re-install

1. Insert the power supply cord into the cord anchorages.

2. Connect the brown wire of the power supply cord

to the fuse holder.

3. Install the green/yellow wire of the power supply cord to the oven cavity with the single (1) screw

tightly.

Blue wire of power supply cord

White wire of main harness

Connector CE-230

4. Make sure that the blue wire and the white wire are stripped for 15 mm length as shown in Figure C-l 1.

5. Wind the conductors of Blue and White wires each other.

6. Insert the stripped wire leads into the connector CE-230.

7. Clamp the connector CE-230 with the correct tool tightly.

Cord anchorage

Brown wire

CE230

Green/Yellow wire

Figure C-8 Power Supply Cord

Replacement

for Australian Model

-7

Blue wire

Page 31

R-3A53 R-3A53B

POWER SUPPLY CORD REPLACEMENT

(FOR NEW ZEALAND MODEL)

Removal

1. CARRY OUT 3D CHECKS

2. Loosen the two (2) screws holding the brown and blue wires of the power supply cord to the cord

connector on the noise filter.

3. Loosen the single (1) screw holding the earth angle

and earth wire of power supply cord.

4. Remove the single (1) screw holding the cord anchorages to the oven cavity.

5. Remove the power supply cord.

Re-install

1. Insert the power supply cord -into the cord anchorages.

2. Insert the brown and blue. wires of power supply cord into the terminals of cord connector, referring to pictorial disgram. And tighten the screws.

3. Insert the earth wire of power supply cord into the earth angle, and tighten the screw holding the earth angle.

4. Tighten the single (I) screw holding the cord anchorages.

5. CARRY OUT 4iJ CHECKS

Noise filter

Cord anchorage

Cord connector

Brown wire

Green/Yellow wire

Earth angle

Figure C-9. Power Supply Cord Replacement

For New Zealand Model

Terminal

Positive lock’ connector

Figure C-IO. How to release the positive lock@’ connector.

Procedure

1. Pushing the lever of positive lock’connector,

2. Pull down the connector from the terminal.

3. Now, the connector is free.

CAUTION: The positive lock@ terminal can not be

disconnected by only pulling. Because once you (Service personal) have connected the positive lock’ connector to the terminal, the positive lock’ connector has been locked.

Page 32

R-3A53 R-3A53B

IST LATCH SWITCH, 2ND LATCH SWITCH,

STOP SWITCH AND MONITOR SWITCH REMOVAL

1. CARRY OUT 3D CHECKS. 2, Remove the control panel assembly referring to

“CONTROL PANEL REPLACEMENT”.

3. Disconnect the leads from all switches.

4. Remove the two (2) screws holding the latch hook to the oven cavity.

5. Remove the latch hook.

6. Remove the switch(s) from the latch hook by pushing the retaining tab backwards slightly and turning the switch(s) on the post.

7. Now, the switch(s) is free.

Latch Hook,

Post

Figure C-l 1. Switches

IST LATCH SWITCH, 2ND LATCH SWITCH

STOP SWITCH AND MONITOR SWITCH ADJUSTMENT

If the 1st latch switch, 2nd latch switch, stop switch and monitor switch do not operate properly due to a mis-adjustment, the following adjustment should be made.

1. CARRY OUT 3D CHECKS

2. Loosen the two (2) screws holding the latch hook to the oven cavity front flange.

3. With the door closed, adjust the latch hook by moving it back and forward. In and out play of the door allowed by the latch hook should be less than

0.5 mm. The horizontal position of the latch hook should be placed where the stop switch and moni-

tor switch have activated with the door closed. The vertical position of the latch hook should be

placed where the 1st and 2nd latch switches have activated with the door closed.

4. Secure the screws with washers firmly.

5. Make sure of the 1 st latch switch,-2nd latch switch, stop switch, and monitor switch operation. If those switches have not activated with the door closed, two (2) screws holding latch hook to oven cavity front flange and adjust the latch hook position.

After adjustment, make sure of following:

1. In and out play of door remains less than 0.5 mm when latched position. First check latch hook posi-

tion, pushing and pulling the door toward the oven face. The results (play of the door) should be less than 0.5mm.

2. The 1st and 2nd latch switches interrupt the circuit before the door can be opened.

3. The monitor switch contacts close when the door is opened.

4. The stop switch contacts open when the door is opened.

5. Re-install outer case and check for microwave leakage around the door with an approved microwave survey meter. (Refer to Microwave Measurement Procedure.)

Door ,

2nd latch switch

Monitor switch

1 st latch switch

Switch lever

Figure C-l 2. Latch switches Adjustment

Page 33

R -3A53 R-3A53B

DOOR REPLACEMENT AND ADJUSTMENT

DOOR REPLACEMENT

1. CARRY OUT3lJCHECKS

2. Remove two (2) screws holding the lower oven hinge to the bottom plate. The lower oven hinge is now free.

3. Open the door by pushing the door open button.

4. Remove door assembly from the upper oven hinge by pulling it forward.

5. Re-install the door assembly to the upper oven hinge.

6. On re-installing new door assembly, secure the lower oven hinge with the two (2) mounting

screws to the oven cavity. Make sure the door is parallel with bottom line of the oven face plate and the latch heads pass through the latch holes correctly.

7. CARRY OUT 4R CHECKS

Note: After any service to the door, an approved

microwave survey meter should be used to assure compliance with proper microwave radiation standards. (Refer to Microwave Measurement Procedure.)

CHOKE COVER REMOVAL

1. Insert an iron plate(thickness of about 0.5mm) or flat type screw driver to the gap between the choke

cover and door panel as shown figure to free the

engaging part.

2. Lift up the choke cover, now cover is free.

DOOR ADJUSTMENT

When removing and/or loosening hinges such as in door replacement, the following adjustment criteria are taken.

Door is adjusted to meet the following three conditions by keeping screws of hinge loose. I. Adjust door latch heads at a position where they

smoothly catch the latch hook through the latch

holes. Refer to latch switch adjustments.

2. Deviation of the door alignment from horizontal line

of cavity face plate is to be less than 1 .Omm.

3. The door is positioned with its face depressed to-

ward the cavity face plate.

4. Reinstall outer case and check for microwave

leakage around the door with an approved microwave survey meter. (Refer to Microwave Measure ment Procedure.)

UPPER OVEN HINGE

DOOR

TCHd ADS

CHOKE COVER

I I

lRo~~

DOOR PANEL

Figure C-14. Choke Cover Removal

DOOR PARTS REMOVAL

Remove the door assembly, referring to from item 1

through item 4 of “DOOR REPLACEMENT”.

1. Place the door assembly on a soft cloth with latch heads facing up.

2. Remove the choke cover, referring to “CHOKE COVER REMOVAL”.

\OUTER

CASE CABINET 3.

LATCH HEAD REMOVAL

Release the latch spring from the tabs of the latch

head.

Release the latch head from the door panel.

5. Now, the latch head is free.

Figure C-l 3.Door Assembly Replacement

and Adjustment

Page 34

R-3A53 R-3A53B

MICROWAVE MEASUREMENT

After adjustment of door latch switches, monitor switch and door are completed individually or collectively, the following leakage test must be performed with a survey instrument and it must be confirmed that the result meets the requirements of the performance standard for microwave oven.

REQUIREMENT

The safety switch must prevent microwave radiation

emission in excess of 5mW/cm2 at any point 5cm or more from external surface of the oven.

PREPARATION FOR TESTING:

Before beginning the actual test for leakage, proceed

as follows;

1. Make sure that the test instrument is operating normally as specified in its instruction booklet. Important:

Survey instruments that comply with the require-

ment for instrumentations as prescribed by the per-

formance standard for microwave ovens must be

used for testing.

Recommended instruments are: NARDA 8100 NARDA 8200 HOLADAY HI 1500

SIMPSON 380M

2. Place the oven tray into the oven cavity.

3. Place the load of 275&l 5ml of water initially at 20 +5”C in the centre of the oven tray. The water container should be a low form of 600 ml beaker with inside diameter of approx. 8.5cm and made of an electrically non-conductive material such as glass or plastic. The placing of this standard load in the oven is im-

portant not only to protect the oven, but also to in-

sure that any leakage is measured accurately.

4. Close the door and turn the oven ON with the timer set for several minutes. If the water begins to boil before the survey is completed, replace it with 275ml of cool water.

5. Move the probe slowly (not faster that 2.5cm/sec.) along the gap.

6. The microwave radiation emission should be meas-

ured at any point of 5cm or more from the external

surface of the oven.

Microwave leakage measurement at 5 cm distance

Page 35

R-3A53 R-3A53B

TEST DATA AT A GLANCE

Parts Symbol

Value / Data

High voltage capacitor

0.94uF AC 2000V

Fuse F

M6.3A 250V

Thermal cut-out (OVEN) TC

145°C

Temp. fuse (MG)

TFI

150°C Temp. fuse TF2 115°C Temp. fuse (OVEN) TF3

150°C Magnetron MG Filament < 1 n

Filament -

chassis 00 ohm.

Oven lamp -.

25W El4 250V Monitor resistor R

0.8Q 2OW

Power transformer

Filament winding < 1 R

Secondary winding Approx. 97.2Q

Primary winding Approx. 1.96fi

TEST POINTS ON CONTROL UNIT

In/Out put terminal

Input (Supply) Input (Stop switch)

Output (Oven ,lamp Fan motor, Turntable motor)

Output (Power transformer) Output (Earth)

Test point

Al - A3 Bl- 82 Al - A5

Al - A7

B2 - Chassis

Volt

240V

Resistance

(Disconnect the power plug

and door is closed)

Approx. 934R

Of2

126Q

2.2n

WARNING: DISCONNECT THE PLUG WHEN MEASURING RESISTANCE.

Page 36

AC CORD CONNECTION BRN : BROWN

BLU : BLUE G-Y :

GREEN AND YELLOW STRIPE

/lB : SECTIONAL AREA

OF 0.75mm2 MIN.

sw1:

1ST. LATCH SWITCH

NOTE: CONDITION

l.DOOR CLOSED

2.CLOCK APPEARS ON DISPLAY

G-4

240V+OHz

TFI: ELOC (MG)

TFJ: EG.

15oc

(OVEN)

0 0

FAN MOTOR

SW2

SWITCH

,b 0

SW3 MONITOR

RMONITOR

SWITCH

H.V. RECTIFIER

L-----J

MGZ MAGNETRON

Figure 0- 1. Oven Schematic-OFF Condition

For Australia Model

% CAUTION:

The temp fuse 15OC m is used for the oven which its serial nu&er is from 9012XxXxX. The thermal cut-out143 E Is used for the oven which its serial number is

till 9011xxxxx.

SCHEMATIC

NOTE: CONDITION

OF OVEN

3.DOOR CLOSED

2.COOKING TIME PROGRAMMED

3.START KEY TOUCHED

TFl: ELiO, MG)

TF3 FEE

15OC

(OVEN)

-T&-v-t

“^“.“.“v

1\-I

SW3 MONITOR

R MONITOR

SWITCH

FEET

ASYMaTRIC RECTIFIER

T: POWW

TFIANSFOF+iEFl

IA 17

H.V. RECTIFIER

TF2 TEbiJ FUSE

115c

SW2 ?!%H

SWITCH

Figure O-2. Oven Schematic-ON

Condition

For Australia Model

Page 37

I CAUTION:

The tenp fuse lS0C Iu la used for the oven which its aerial number 1s from S012XXXXX. me thermal cut-out U; la used for the oven which its serial number is from S011XXXXX.

NOISE FILTER

I ”

I IO.O022), _

I I 0.002a

1 I

BYPASS CAPACITOR

IOU

------------------i

AC CORD CONNECTION

BROWN k?: i BLUE G-Y :

GREEN AND

YELLOW STRIPE /lB : SECTIONAL AREA

OF 0.75fntn2 MIN.

sw1:

TF3: TEW FUSE 15oc (OVEN1

TF2 zs FUSE

TFJ: TEEP FUSE

150 c (OVEN)

TF2 ::z FUSE

SW% IST. '

LATCH SWITCH ”

IST. LATCH SWITCH

SW2 ?ZCH

SWITCH

SCHEMATIC

NOTE: ;$JN;lX;ON

CCNTROL UJIT

--_---_

;

SW2 2la. LATCH SWITCH

SCHEMATIC

NOTE: CONDITION

r-l

OF OVEN

l.DOOR CLOSED

1. I73014 CLOSED

2.COOKING TIMED PROGRAMMED

3.START KEY

2.CLOCK APPEARS ON DISPLAY

RMONITOFI

SWITCH

Fx?

------l-

SW3 MONITOR

R MONITOR

SWITCH

!F::%F

r--

--I

I::::

-I-

H.V. RECTIFIER

L------J

m MAGNETRON

Figure O-3. Oven Schematic-OFF Condition

For New Zealand Model

H.V. RECTIFIER

L-----l

UG: MAGNETFi0N

Figure O-4. Oven Schematic-ON Condition

For New Zealand Model

Page 38

R: MONITOR

RESISTOR

TTM: TURNTABLE

SWi: 1ST LATCH

HIGH VOLTAGE

%: Positive Lock

(NO-Case Type)

See page 30,

H.V.RECTIFIER

Figure S-l. Pictrial Diagram( For Australian Model)

til

Page 39

R-3A53 R-3A53B

. .

k. is

..oG

--+X0 ILWUY l-l----d

w5 I%

@ $zg r’“-” ~ ,,,

waai--I

fk f

/* i

h z

z =E!

+ io

.I It

3 4 5

Page 40

R -3A53 R-3A53B

1 2

3 4 5 6 ’

;: s

r.@

--.

;; 5 $5 8 8

- z P 4

__A

”

“I ...

VXWET

gL&+mr- --j

:I + $5

$$;

1 ’ is E $’

-, i-i

r- -7

is s: 3

ci m’

3 ci

i3 Ii

n lo

z E

0 i

z g

Page 41

R-3A53 R-3A536

I-

-1

1 2 3 4 /

* ,

’ m,BFA~ 26

Figure S-4. Printed Wiring Board

------I

Page 42

R-3A53 R-3A53B

PARTS LIST

Note :

The voltage supplied to the parts “*” are greater than 250V.

REF. NO. 1 PART NO.

DESCRIPTION

1 Q’TY ICODE

* *

l- 1 l- 2

l- 3 l- 4 l- 5

l- 6 l- 7 l- 8 l- 9 l- 9

l-10 l-11

l-12 l-12 l-13

l-14 l-15

l-16 l-17 l-18

l-19 l-20

ELECTRICAL PARTS

QFSHDA002WREO Fuse holder (For Australian) QFS-TA014WREO Temp. fuse 150°C (MG)

QSW-MA007WREO 1st latch switch (V-5230D-069) QSW-MA009WREO Monitor switch (V-5220D-070) FW-QZA068WRKO H.V.

rectifier assembly

--____ QFS-TA014WREO Temp. fuse 150°C (OVEN)

RC-QZAllSWREO High voltage capacitor FMOTEA208WRKO Fan motor with fan blade QACCAAOllWREO Power suplly cord (For Australian) QACCAA018WREO Power supply cord (For New Zealand

QFS-C0019WREO Fuse M6.3A QFS-TAOlOWREO Temp. fuse 115°C

RV-MZA129WREO Magnetron (.For New Zealand) RV-MZA130WREO Magnetron (For Australian) QSOCLAOllWREO Oven lamp socket

RLMPTA029WREO Oven lamp RMOTDA086WREO Turntable motor

RR-WZA003WREO Monitor resistor 0.8n 20W RTRN-A282WREO Power transformer FPWBFA214WRKO Noise filter (For New Zealand)

QSW-MA007WREO 2nd latch switch (V-5230D-069) QSW-MA007WREO Stop switch (V-5230D-069)

1 1

1 1 1

1 1 1 1 1

1 1

t 1

1 1

CABINET PARTS

AE AG

AF AF AY

AG AW

BA AP AP

AG AG

BL AH

AK AP

AX AF

2- 1 2- 1 z - - l-2

l-3

2- 2 2- 2

2- 3 2- 4 2- 5

FFTASAO35WRKO Oven lamp access cover assembly (R-3A53) FFTASA051WRKO Oven lamp access cover assembly (R-3A53B) PCUSGA306WRPO Cushion PSLDPAOOSWRPO Lamp

reflector

GCABUA306WRPO Outer case cabinet (R-3A53) GCABUA347WRPO Outer case cabinet (R-3A53B)

FDAI-A135WRWO Bottom plate FHNG-AO96WRTO Lower oven hinge

GLEGPA023WREO Foot

AN AN AA AD

-BD

AW AK AB

CONTROL PANEL PARTS

3- 1 CPWBFA441WRKO Control unit(New Zealand only) 3- 1A QCNCMA078DREO $-pin connector (A)

- 1B

QCNCM0027WREO 2-pin connector (B)

- 1c

QCNCWA03ODREO 12-pin connector (D)

3- 1D RV-KXA037DREO Fluorescent display tube

RC-KZA032DREO Capacitor O.lpF 50V ~

VCEAB31VW108M Capacitor

1000pF 35V

VCEAB31EW476M Capacitor

47pF 25V .

C6,7,20,VCKYBllEX103N Capacitor

O.OlpF 25V

C21,40

c50-53

VCKYDllHB331K Capacitor

330pF 50V

C80

VCEAB31HW104M Capacitor

O.lpF 50V

C81

VCEAB31HW225M Capacitor

2.2pF 50V

C82

VCEAB31HW335M Capacitor

3.3pF 50V

c90 VCC-F31H-680J Capacitor

68pF 5ov

c91

VCC-F31H-181J Capacitor

CF90

180pF 5ov

RCRS-2008DRE0 Ceramic filter KBRGOOB (6OOkHz)

Dl-5

VHDllESl///-1Diode (11ESl)

D50-57, VHDlSS270A/-1Diode (lSS270A)

D80-83

1 BP 1 AD

AB ; AE 1 AU

1 AB

; AB 5

4 AA

i AA 1 AA 1 AA

1 AB 1 AF 5

12 AA

ICl

RH-IZA377DREO LSI

1 AR

VS2SB910MR/-4 Transistor (2SB910MR)

1 AC

Q20,82

VSDTC114ES/-3 Transistor (DTC114ES)

2 AB

VSDTA114ES/-3 Transistor (DTA114ES)

1 AB

VSDTD143ES/-3 Transistor (DTD143ES)

1 AC

Page 43

R-3A53 R-3A53B

Note : The voltage supplied to the parts rr*n are greater than 250V.

PART NO.

DESCRIPTION

REF. NO.

R2 R3 R4 R5 R6

R10 R7,11,21 R30 R31 R40

R41 R50-53 R150-15' R80 R81

R82 R83 R90 RYl RY2

-~ SP30 Tl VRSl ZDl ZD2

-ZD3 ZD10,20 3- 2

3- 3

3- 6 3- 7

VRD-B12HF272J Resistor

2.7kn 1/2W

VRD-B12HF102J Resistor

1kQ 1/2W

VRD-B12HF112J Resistor

l.lkn 1/2w

VRD-B12EF82lJ Resistor

82OzT 1/4W

VRN-B12EK392F Resistor

3.9kir (F) 1/4W

--VRD-B12EF123J Resistor

12kn 1/4W

VRD-B12EF103J Resistor

1Okn 1/4w

VRD-B12EF102J Resistor

lkn 1/4W VRD-B12EF332J Resistor 3.3kf2 1/4W VRD-B12EF473J Resistor

47kR 1/4W

VRD-B12EF563J Resistor

56kQ 1/4W

VRD-B12EF183J Resistor 18kQ 1/4W

VRD-B12EF623J Resistor

62kS2 1/4W

VRD-B12EF471J Resistor

47OQ 1/4w

VRD-B12EF201J Resistor

VRD-B12EF39GJ Resistor

200R 1/4w

39R 1/4w

VRD-B12EF122J Resistor

1.2kn 1/4W RRLY-A020DREO Relay (OJ-SH-112LM) RRLY-A059DREO Relay (VS14MB-NR)

RALM-AO14DREO Buzzer (PKM22EPT-CA) RTRNPA064DREO Transformer RH-VZAOlODREO Varistor (TNR15G471K). VHEHZ12Bl//-1 .Zener diode (HZ12B-1) VHEHZGC2///-1 Zener diode (HZ6C-2)

EEHZGA3///-1 Zener diode (HZ6A-3) VHEHZllA3//-1 Zener diode (HZllA-3) HPNLCA884WRFO Control panel frame (R-3A53) HPNLCA980WRFO Control panel frame (R-3A53B) DUNTKA479WRKO Key unit assembly (R-3A53)

-~DUNTKA480WRKO Key unit assembly (R-3A53B) GMADIA054WRFO Display window JBTN-A680WRFO Open button (R-3A53) JBTN-A677WRFO Open button (R-3A53B) MSPRDA014WREO Open button spring

XEPSD30PlOXSO Screw; Control unit mtg.

OVEN PARTS

4- 1 4- 2

;I j 4- 5

FROLPA050WRKO Roller stay NTNT-A034WRFO Turntable PPACGA054WREO Cushion

MLEVPA171WRFO Switch lever

PHOK-A062WRFO Latch hook

4- 6 ;I ;

4- 8-l 4- 8-2

4- 8-3 4- 8-4 4- 9 4-10 4-11

-____ 4-12 4-13 4-14 4-15 4-16

4-17 -4-18 4-19 4-20 4-21

LBNDKA038WRPO Capacitor holder

MHNG-A225WRTO Upper oven hinge

DOVN-A314WRKO Oven cavity assembly FOVN-A233WRTO Oven cavity LBOS-A042WREO Waveguide stub

XBPUW50P08000 Screw XWSUW50-13000 Washer LX-WZA028WREO Washer LSTPPA069WRFO Cord anchorage (upper) LSTPPA070WRFO Cord anchorage (lower)

PCLIC0026WREO P-clip PCOVPA208WRFO H.V.C. cover PCOVPA241WREO Waveguide cover PPACGA073WREO Trans. cushion

PCUSUA190WRPO Cushion

---PDUC-A395WRFO Air guide PDUC-A399WRWO Air duct PFILWA041WREO Lamp filter PPACGA097WREO O-ring LANGQA167WRMO Earth angle (For New Zealand)

DOOR PARTS

Q’TY

1 1 1 1

1 1

3 1 1 1

1 1

1 1 1 1

1 1 1

; 1

2 1 1 1

1 1

1 3

1 1 1 1 1

: 1 1 1

1 1 1 1 1

1 1

1 1 1 1

AB AA AA AA AA

AA AA

AA AA AA

AA AA

AA AH AK

AG AS AE AB AA

AC AA AR

BA BA

AG AG AC

AC AF AP

AH AG BN BN AG

AP AB AB AD AC

-AA AF AL AD AC

AG AP AA AG AC

DDORFA493WRKO Door assembly, complete (R-3A53)

1 BK

DDORFA498WRKO Door assembly, complete (R-3A53B)

1 BK

Page 44

R-3A53 R-3A53B

Note :

The

REF. NO.

-1

;- 1

5- 2 5- 2 5- 3

5- 3

- 4 z- 4 5- 5 5- 6

voltage supplied to the parts m*” are greater than 250V.

PART NO.

DESCRIPTION

1 Q’TY ICODE

FDORFA199WRTO Door panel (R-3A53)

~ l

FDORFA195WRTO Door panel (R-3A53B)

1 BC

GCOVHA229WRFO Choke cover (R-3A53)

1 AK

GCOVHA227WRFO Choke cover (R-3A53B)

1 AM

HPNL-A364WREO Door screen (R-3A53)

HPNL-A369WREO Door screen (R-3A53B)

LSTPPA091WRFO Latch head (R-3A53)

LSTPPA089WRFO Latch head (R-3A53B)

MSPRTA081WREO Latch spring

PSHEPA333WREO Sealer film

MISSCELANOUS

6- 1 6- 2 G- 2 6- 3 6- 3

6- 3 G- 4 6- 5 6- 6 6- 7

;I “9

6-10

TINS-A268WRRO Instruction book FW-VZB043WREO Main wire harness (For Australian) FW-VZB047WREO Main wire harness (For New Zealand) TSPCNB514WRRO Rating label (For Australian R-3A53) TSPCNB522WRRO Ratina label (For New Zealand R-3A53)

TSPCNB523WRRO Rating label (For Australian R-3A53B) QW-QZA136WREO High voltage wire A FW-VZA910WREO Switch harness QTANP0020YBEO Connector CE-230 TCAUHAOSSWRRO Caution label

TCADCA323WRRO Cookbook TGAN-A002WRRO Guarantee card (For New Zealand) TCAUH0123WRRO Micro caution (For New Zealand)

1 1 1 1 1

AK AY AY AG AG

AG AH AL

AF AS

1 AE

SCREWS AND WASHER

7- 1 XOTSD40P12000 Screw; M4 x 12 zinc plated steel

7- 2 XHTSD40P08RVO Screw; M4 x 8 zinc plated steel

7- 3 XHSSE40P08000 Screw; M4 x 8 (R-3A53)

7- 3 XHSSF40P08000 Screw; M4 x 8 (R-3A53B)

;

7- 4 LX-CZA029WREO Special screw (LHSTIX R-4)(For Australian)

7- 5 LX-CZ0052WREO Special screw

7- 6 LX-EZA036WREO Special screw

c- - 7 7 XOTSE40P08000 Screw; M4 x 8 (R-3A53)

XOTSF40P08000 Screw; M4 x 8 (R-3A53B)

7- 8 XWSSD40-10000 Washer;

7- 9 XBTSD40P08RVO Screw;

7-10 XFPSD30PlOOOO Screw; M3 x 10

7-11 XFPSD40P08KOO Screw; M4 x 8 zinc plated steel

7-12 XFPSD40P08000 Screw; M4 x 8 zinc plated steel

7-13 XFPSD40P30000 Screw; M4 x 30 zinc plated steel

7-14 XOTSD40P12RVO Screw; M4 x 12

7-15 XWUSE40-05000 Washer;

HOti TO ORDER REPLACEMENT PARTS

To have your order filled promptly and correctly, please furnish the following information.

1. MODEL NUMBER 2. REF. NO.

3. PART NO. 4. DESCRIPTION

AA AA AA AA AA

AA AA

AA AA AA AA AA

AA AA

Page 45

R-3A53 R-3A53B

,A5 -’

I I

For Austraha

I I I

4 5

Page 46

CONTROL PANEL PARTS

6-3

(ForAuss$

DOOR PARTS

/’

r I I I I I I I

I I I I I I I I I I I

I I

I I I

I I

I I I

I I

I I I I I

I I

I I I I I

I I I

I I

I I I

I I

I I I

I I

I I I

I I

Page 47

MISCELLANEOUS

%PACKlNG PAD KIT

(CPADBAlOSWRKO)

.A,

PACKING AND ACCESSORIES

TURNTABLE TRAY

Fi-3A53B, Australia

ROLLER STAY

DOOR PROTECTION SHEET

(SPADPA204WREO)

MICROWAVE OVEN

SHRINK FILM SHEET

% Not Aepkxable items

SPAKCB767WREO R3A53,Austraha SPAKCB775WREO.R3A53B,Australia SPAKCB774WREO:R3A53,New Zealand

1 2 I

3 4

5 6

‘91 0 SHARP CORP. (7K0.93E) Printed in Australia