Sharp R-5H53 Service Manual

R-5H53

SHARP SERVICE MANUAL

s9111 R5H53J::

MICROWAVE OVEN

MODEL

in interests of user-safety the oven shcutd be restored :G .;s ,~rrg,r;d’
condition and oniy manufacturer orlginal svare qarrs -nus; x ~sec:

-‘i-c _

TABLE OF CONTENTS

Fage

APPEARANCE

VIEW

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

. . INSIDE

COVER

GENERAL

IMPORTANT

INFORMATION

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

. . . .

. .._.......... I

CAUTION, MICROWAVE RADIATION,WARNING ,,.......,.,..,..,,....,......,,.....,...,...,.,,....................,..,.,....,...... 1

PRODUCT SPECIFICATIONS

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

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

2

OPERATION

SEQUENCE

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

..

3

FUNCTION

OF IMPORTANT

COMPONENTS

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

..,....

4

SERVICING

. . . . . . . . . . . . . . . . . . . . . . . ..*..............................................................................................................................

5

TEST

PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TOUCH

CONTROL

ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDl
MICROWAVE

MEASUREMENT

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

WIRING

DIAGRAM

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

PICTORIAL

DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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

6

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

16

RE .....................................................

23

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

27

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

28

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

29

CONTROL PANEL CIRCUIT

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

30

PRINTED WIRING DIAGRAM

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

31

PARTS

LIST

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

32

PACKING

AND

ACCESSORIES

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

38

SHARP CORPORATION

R-5H53

APPEARANCE VIEW

1. Ventilation openings

2. Oven lamp

3. Oven door with see through
window

4. Coupling

5. Roller Stay

6. Removable turntable

7. Hinges

8. Safety door latches

9. Door open button

10. Touch Control Panel
1 1. Digital readout

12. Waveguide cover

13. Access cover for oven
lamp replacement

Touch Control Panel

SENSOR INSTANT ACTION

1

f

I

-SENSOR !&ANT ACTlOb -

PADS

J

Touch once to cook or reheat

4 popular menu.

iRESh ‘VEGETABLES

II

REHEAT ’

BEVERAGE

1 -NUMBER PADS

k
L

I /
!=

i­/

&
r-

-­I

r=

t

/
1

I
1

1
/

I
1

/
I

I

/

-I

+-

C
r

t

SENSOR COOK PADS

Touch to select Fresh or

Frozen foods In Sensor modes.

(
I

SENSOR COOK MENUS~-----l~

EASY DEFRQST PAD

/ i

Touch to defrost
entering weight.

MEMORY

Touch to enter one frequently
used cooking programme.

Touch to recall the memorized

programme.

I

VARIABLE COOKING
CONTROL PADS

power setting.
If not touched, HIGH is auto­matically selected.

STOP/CLEAR PAD -------l j

L

Touch to erase during pro­gramming.
Touch once to stop operation
of oven during cooking: touch
twice to cancel cooking pro­gramme.

SENSCG C03K

’ Ross’ bee:

Z qoast lamb

cioast zh1cke.n

1 c

4 Lorned ;nea!
5 Desserts
0 Cake / Pudciric

7 Stewed iruc:

b Preserves

iI

I

9 Bacon

lC Porrlcge

ii 6 1

11 SOUP

It

12 Casserole:
?3 Fish fillets

j/ 7 i

1.4 Fice

!I

J

15 Pasta

16 Frozen o!nners

l? Pastrces

js/

- MEMaRY
I

*Place the roller stay on the

coupling in the oven and seat the
turntable on the roller stay.

I
i­I

Touch to enter cooking times,
clock time, weight or quantrty
of food, or to select the Sensor
Cook menus.

-MORE( I\ 1, LESS{ v 1 PADS

1 1
! 1

,
I
i j

I 1
I ;

i 1

Ji

IL

,

1

Touch to increase/decrease
the time in one minute incre-

ments during cooking or to

alter the doneness for the
Sensor Cook, Sensor instant
Action or Easy Defrost modes.

--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.

r

AUTO START/CLOCK PAD

Touch to set clock or Auto

’ Start time.

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R-5H53

PRODUCT DESCRIPTION

SPECIFICATIONS

ITEM

Power Requirements

240 Volts
50 Hertz

DESCRIPTION

Single phase, 3 wire earthed

-____

Power Consumption

1500w

__----- ---_

___----

Power Output

750 watts nominal of RF microwave energy (2 litre water load)
850 watts (IEC-705 1988)
Operating frequency of 2450M Hz

_---

Case Dimensions

Width 616 mm

Height 366 mm
Depth 477 mm

Cooking Cavity Dimensions

--____
Control Complement

Width 406 mm

, Height 248 mm

Depth 422 mm

’ Touch Control System

Clock( I:00 - 12:59 )

Timer (0 - 99 min. 99 sec. )

Microwave Power for Variable Cooking

Repetition Rate;

HIGH

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Full power throughout the cooking time

MED

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

approx. 70% of Full

Power

MED

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

approx. 50% of Full

Power

MED LOW (DEFROST)

. . . . . . . . . . . . . . . . . . . . . . . . . . approx. 30% of Full Power

LOW

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . approx.

10% of Full

Power
SENSOR COOK (Fresh 1 -- ‘I 5, Frozen 11 -- 17)
INSTANT COOKSTART
AUTO START
MEMORY

Se! Weig n:

SENSOR INSTANT ACTION
EASY DEFROST
MORE/LESS pads

Approx. 23 kg

NOTE: Numbers and letters shown after sentences such as “RD44101 U” are for factory use only.

2

R-5H53

OPERATION SEQUENCE

ription of component functions

The fo llowing is a desc
during oven operation.

OFF CONDITION

(RD7:“O:U;

Closing the oven door activates all the door interlock
switches: upper latch switch and lower latch switch.
(In this condition,

the monitor switch contacts are
opened.) The stop switch is activated by the latch
head.

When oven is plugged In, 240 volts A.C. IS
supplied to the control unit. But no components in ine
oven will operate. (Figure O-l on page 28)

1. The display will show flashing “88:88”,

2. To set any program or set the clock, you must touch

the STOP/CLEAR pad first.

3. The dispiay WIII clear and ” ” appears in :he d;.-;-

play and the time

counts up every minute:.

NOTE:When the door is opened by pushrng the door

open button, the contacts of :he reiav RY -1 sre
closed, ther! rhe oven

kmp lights.

MICROWAVE COOKING CONDlTfON

HIGH COOKING

Program desired coctk~ng trme and Variaole Cook+ng
Control by touching ?he NUMBER pads and the HiGti
pad of the Variabi

e Cooking Cont:ol. When rhe STP?,T

pad is touched,

the foiiowing operations occur:

1. The contacts of reiays closed and components
connected to the relays are turned on as foilovds.

(Figure O-2 on page 28’1

~__. I---

Relay

cOcnt?C:ed ccmoGnet77is

__~_ .-._.- --_-- _~-- __ _________

RY-1

Oven lamp,Turncable rrotor Fan motor

RY-2

Power Transformer

-______--

2. 240 volts A.C. is supplied to the primary winding
of the power transformer. The voltage is converted
to about 3.3 volts AC. output on the filament
winding and approximately 2000 volts A.C. high
voltage on the secondary winding.

3. The 3.3 volts filament winding voltage heats the
magnetron filament and the 2000 volts high voltage
is sent to the voltage-doubling circuit, where it is
doubled to a negative voltage of approximately

4000 volts D.C.

4. 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.

5. Upon completion of the cooking time, the power

transformer, oven lamp, etc. are turned off, and the

generation of microwave energy is stopped. The
oven will revert to the OFF condition.

6. When the oven door is opened during a cooking
cycle, the monitor switch. upper and lower latch
switches are activated with the followrng resuits.
The crrcuits to the turntable motor, fan motor and

high voltage components are deenergized, the oven
lamp remains on,

and the digital readout displays
the time still remaining in the cook cycle when the
door was opened.

7 The monitor switch IS electrrcally monrtoring the

operation of the upper and !ower latch switches and
6 mec5ts nrcally associated with the door so that !t
jNi!i funGion tn the foilowtng sequence.

(1 ) ‘v?ihen the door is opened from a closed posi-

Thor;. the upper larch and lower latch switches
operate to open their contacts first, and then
Ihe

sontacts of

the monrtor swatch ciosed and

the :contacts of the stop switch open.

t 21 Wheq the door IS closed from the open position,

:ne comacts oi rhe moG:iIor switch should be
craned firs: and rhe ,zontac;s of :he stop swatch
ar;>

ziosec and ther tipcer !atch and lower

;atc,les are ZiGsee,

/ T’

*

-?cs sf 1,113 ap~?r ap‘-j ;c;Q-~>~: ;aTcjy

di LV

5wttch switches

;a’: wit’r: -:p,eir {be “,o~~tac:s l;i:>~e~:i i,\!ken -,he doOr -

!2

pr.C;n!AA

vyv* i”.A,

T r; e

ccjcn:::zr S\$/iiCh \.A/;ii

form s short c:rc;:i;

Thro!-:cjh ‘h? :‘i!$+ and ihe ‘-!pLy?r _31?c ‘cJ\n/ef ja:ch

ftise

s*jk ctc:?es

i:du~;f-~ :pe fus5 tfj brr~~,y

MED HIGH, MED; MED LOW (DEFROST), LOW
COOKING
When :iarrabie Cooking - Power 1s programmed, the 240
voits A.C. is supplied to the power transformer
rntermittent!y through the contacts of relay! RY -2)
which is operared by the control unrt within a 32 sec­ond time base. Microwave power operation IS as fol-

iO\NS:

_.____

VARI-MODE

ON TIME

OFF TIME

-__.

HIGH

32 sec. 0 sec.

(100% power)

-__

MED HIGH

24 sec. 8 sec.

(approx. 70% power)
MED

18 sec. 14 sec.

(approx. 50% power)
MED LOW (DEFROST) 12 sec.

20 sec.

(approx. 30% power)
LOW 6 sec. 26 sec.

(approx. 10% power)

Note: The ON/OFF time ratio does not correspond

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

(RD71401 U)

3

R-5H53

FUNCTION OF IMPORTANT COMPONENTS

DOOR OPEN MECHANISM

The door can be opened by pushing the open button
on the control panel, refer to Figure D-l. When the
open button is pushed, the open plate on the open
device pushes in the door lever on the door, operating
the latch head linkage.

The lower and upper latch
heads are moved upward, and released from the lower
and upper latch hodks. Now, the door can be opened.

(RD72GOl U;

\

UPPER
LATCH

LOWER

HEAD

LATCH

HEAO

DOOR

OPEN
BUT-TON

Figure D-l.

Door f)pen Mechanism

UPPER AND LOVVER LATCH SWITCHES

The lower latch switch IS mounted in the lower latch
hook and the uppe! latch switch is mounted in the
uoper latch hook.

They are activated by the latch

heads on the door.

When the door is opened, their

switches interrupt the circuit to all components except
the oven lamp and touch contra! panel. A cook cycle
can not take piace until the door is firmly closed there
by activating both interlock switches.

MONITOR SWITCH

The monitor switch is activated (the contacts opened)
by the upper latch head on the door while the door is
closed. This switch is intended to render the oven in­operative by means of blowing the fuse when the
contacts of the upper latch switch and the lower latch
switch fail to open when the door is opened.

Function

1. When the door is opened, the monitor switch con­tacts close (to the ON condition) due to their being
normally closed. At this time the upper latch switch
and the lower latch 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 opened first and then the con-

tacts of upper and lower latch switches close. (On
opening the door, each of these switches operate

\

tnverselv.)

3. If the door is opened and the contacts of the upper

latch switch and lower latch switch fail to open, the
fuse blows simultaneously with closing of the
monitor switch contacts.

CAUTION: BEFORE REPLACING A BLOWN FUSE,

TEST UPPER LATCH SWITCH, LOWER

LATCH SWITCH, MONITOR SWITCH

AND MONITOR RESISTOR

FOR

PROPER OPERATION.

(REFER TO

CHAPTER “TEST PROCEDURE”).

Figure D-Z Latch Switches and Monitor Switch

MAGNETRON TEMP. FUSE

The temperature fuse located on the cavity top plate
near the magnetron to prevent damage to the
magnetron if an overheated condition develops in the
tube due to cooling fan failure, obstructed air ducts,
dirty or blocked air intake, etc.
Under normal operation, the temperature fuse remains
closed. However, when abnormally high temperatures
are reached within the magnetron the temperature fuse
will open at 115’C, causing the oven to shut down.

This is a fuse and it does not reset.

OVEN THERMAL CUT-OUT

(‘RD72403U)

The thermal cut-out located on the wall of the steam
duct. It is designed to prevent damage to the oven
cavity, if foods in the oven catch fire due to over heat­ing produced by improper setting of cooking time or

failure of control unit etc..

Under normal operation, the oven thermal cut-out re-

mains closed.

However, when abnormally high tem­peratures are reached within the steam duct, the oven
thermal cut-out will open at 115OC, causing the oven
to shut down.

(‘RD72407U)

R-5H53

SERVICING

WARNING TO SERVICE PERSONNEL

Microwave ovens contain circuitry capable of producing very high voltage ;;nd current, contac:
lowing parts:

yjj;n ;oi -

High voltage capacitor, Power transformer, Magnetron, High voltage re

ctifler assembly, High vo;;age 7a~ness.

REMEMBER TO CHECK JiJ

1) Disconnect the supply.

2) Door opened, and wedged open.

3) Discharge high voltage capacitor
’ WARNING AGAINST THE CHARGE OF THE

HIGH-VOLTAGE CAPACITOR

The high-voltage capacitor remains ,zharged
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 hrgh-voltage rectifier:
against the chassis with the use of an insu­lated screwdriver.

Sharp

recommend that

wherever possibie
fault-finding is carried out wirh the suppiy discon­nected. It may in, some cases, be necessary to
connect the supply after the outer case has been
removed, in this event carry out 30 checks and then
disconnect the leads to the primary 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 3[3, checks and reconnect the
leads to the primary of the power transformer.

REMEMBER TO CHECK B

11 Reconnect all teads removeo fro,m car-

: , D (2 :- 2 :? ; c

_-

during testing.

2) Replace the ourer case i,catsl!nel;

3) Reconnect the suppiy
a?;

Run the oven Checic ail ftii;ct:cr;s

Microwave ovens should not be ru:; ?rn~:\. T~l -0s~
for the presence of m;Zrovvave 3nerf~v JV::-~~:” s

3

cavltjf, p/aca a czg of CsiC; :~a:?-‘-’

‘2 r

, ‘?~e 3~ ?r~

‘,urc:table, close the dt>or acl:! set Fe ;~s~:~:e~.b,~~+t~

timer for two (2) lmjc:L;les. ~53: r,ble ,qc:-j5r 12~ 1 -;

H iGH and pusi? the ST;;=- z~:tfi=

.iui.

'l',jr‘t! r’?t

T i,‘i; 2

.q:qutes has $iapsed , ‘;j,~e: 3? 7~r5 ~:a:?mii~~ I~-?.::.

.A% -v

rha;

the water 2s new 70: !f :h* :,v&er ;erya;rs 2-i~
carry 0~1 3C checks 3cd s-,3,y~~ire :?,E -:­nections to the corn~o~e:-: 5eifig xstss!

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.

(RD81 GO1 H)

TROUBLESHOOTING GUIDE

When troubleshooting the microwave oven, it is helpful
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 in the
monitor-upper latch-lower latch switch
circut, check the monitor switch, upper
and lower latch witches and monitor
resistor before reolacina the fuse.

R-5H53

TEST PROCEDURE

POSSIBLE
CASE AND
~;X'~~TIVE

ONDITION

PROBLEM

)FF
:ONDITION

N
ONDITION

ENSOR
30KING
3NDITION

Home fuse blows when power supply cord i:
plugged into wall receptacle.

FUSE M8A blows when power supply cord is
plugged into wall receptacle. (The door is closed]

“88:88” does not appear in display but powel

supply cord is plugged into wall receptacle.

Display does not operate properly wher
STOP/CLEAR pad is touched. (An audible signa
should sound and time of day should appear or
display.

Display appears, but oven lamp does not light
with door open.

When the door is opened, fuse M8A blows,
Fan motor does not operate.

(Display appears)

Turntable motor assembly does not operate

(Display appears)

Oven lamp does not light.
(Display appears)

Home fuse or breaker operates when the IN­STANT COOK/START pad is touched.

oven seems to be operating but little
or no heat is produced in oven load. (Microwave
cooking control is set at FULL POWER position.)

Oven does not cook properly when programmed
for variable cooking powers. (Oven operates
properly at FULL POWER)

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

Oven stop as soon as when the INSTANT
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Oven does not cook properly when programmed
in the EASY DEFROST cooking mode. (Oven op­srates properly by manual cooking mode.)

&en is in the sensor cooking condition or one
iouch reheat cooking condition, but AH sensor
does not end 1st stage or does not stop cooking
cycle or the oven stops soon.

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R-5H53

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7

R-5H53

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.

I

CARRY OUT 3D CHECKS

Isoiate 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 replaced

MICROWAVE OUTPUT POWER (2 liter water load)

(RD82AOl Uj

The following test procedure should be carried out with the microwave oven in a fully assembled
conditron (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.
calorie is generated.

When P(W) heating works for t(second), approximately P x t/4.2

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

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

-

The formula is as follows;

P x t /’ 4.2 = V x AT

P (W) = 4.2 x V x CIT : t

:Cld:r condition for the water load !s as follows:

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

Water load . . . ...2300 mi

Initial temperature

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

. . . . . IO+1 ‘C

P = 75 x CT

Heating time . . . . . . 1 min. 52 sec. ~

I

Vieeasurin~ method:

Li,‘i Use two i iitre Pyrex beakers with a diameter of approximately of 7 2cms.

51

Place i iitre of 1 O’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.
Dj Piace th t e wo beakers as touching each other in the centre of the cavity.
E) Set the timer to f minute and 52 seconds at 100% power (the time required to raise the water

temperature 7 0 degrees C.)
FI 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

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

Temperature after 1 min. 52 set

Tl =lO”C T2=11”C

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

Temperature difference Cold-Warm

Tl = 20°C T2 = 21 “C

= =

Mean temperature rise AT

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

ATI 10°C AT2 10°C

. . . . . . . .

Measured output power

AT = (AT1 +AT2) / 2 = (IO’C + 10°C) / 2 = 10°C

The equation is “P= 75 x AT”

---

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*.................

P= 75 x 10°C = 750 Watts

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

1

power.

CAUTION: 1°C CORRESPONDS TO 75 WATTS.

REPEAT MEASUREMENT IF THE POWER IS INSUFFICIENT.

8

R-5H53

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

I

q-1 OC)

iT2 OC!

i-r: OCi

o-2 “Cl

Hea: up for I mm. 52 set

MICROWAVE OUTPUT POWER (lEC-705-1988)

The following test procedure should 5e carried out with :he mtc:ob~,ave oven in a fuiiy assembled
condition (outer case fitred j I

Microwave output power from the magnetron can be measured by
way of IEC 705. i.e. it can be measured by using waIer load how +m:~ch I: car: be absorbed by the
water load. To measure the microwave output power !r! the microwave ov?g, the reiatton of [;a;­orie and watt is used. When PtW! heating works for t(second), ar=erox,ma:eiv
is generated. On :he other hand

P x t, 4 18: calorie

If :he temperature oi Ihe water JV!T~ 4::~:i‘; VISES AT ; C: durlnc:

this microwave heating per:od, the Calorie *z~f rhe wager is ‘V x AT

The formula is as follows:

Pxt

a,?87 = L, x 2-T

p p/) = 4 18: ,y ‘,I .‘( ‘\T

:

Our condition for the water ioad is as foiiows:

Room temperaturF

.I.. ,.. . . .

arouna 20-G

Waler load

. . . . . . . . SO0 g

?o\,j/er SCCClt ‘joitage

P = 85 x AT

Iriit!ai tempera:l;re . . . . . .I 0 12-C

Heat:ng Lime

~- --- --~--.-- ~~ - --~ --

Rated *image

49 set

Measuring condition:

1. Container
The water container must be a cylindrrcal borosilicate glass vessel naving a maxrmum mater!ai
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 test.

3. Temperature of the water
The initial temperature of the water is (10 f 2)X.

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 scaied 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.

Measuring method:

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

2. Add the 7 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 value n T of
(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. Calculate the microwave power output p in watts from above formula.

Initial temperature

__.-___--

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

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

Tl = 11°C

9

R-5H53

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER COMPONENT TEST

Temperature after

(49 + 2) =

51

sec.

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

T2 = 21 “C

Temperature difference Cold-Warm

.,.................................................,..........,..... ATI = 10°C

Measured output power

The equation

is “P= 85 x AT” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

P= 85 x 10°C = 850 Watts

-_____ -___

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

output power.

CAUTION: 1°C CORRESPONDS TO 85 WATTS. REPEAT MEASUREMENT IF THE POWER IS

INSUFFICIENT.

T2”C

*eal up for 51 sec.

(RD82A03U)

B POWER TRANSFORMER TEST

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

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.

:ZkFFk’ 3:-lT

32 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 continurty of al! three windings. The following readings
shouid be obtained :-

a. Primary wrnding ----------less than 7 .5 ohms.

5. Secondary winding -------80 ohms.

c. Filament wending ---------less than 2 ohm.

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

should be replaced.

CARRY OUT 4J CHECKS

(RD82405J1

c 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-CC of the high voltage rectifier and note the reading obtained. Reverse the meter leads and note

IO

R-5H53

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

this second reading. The normal resistance is infinite in one direction and more than 100 k!2 In
the other direction.

CARRY OUT 4R CHECKS
ASYMMETRIC RECTIFIER TEST

CARRY OUT 3D CHECKS.

*qzL ‘JOLTAGE

REcT,F,ER

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 zc:oss the :ermlnals
ATB 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 as:/mme:ric rectifier

is good. If an asymmetric rectifier is shorted in either direction, then the :he asymme:r:c ecrliier
is probably faultly and must be replaced with the high voltage rectifier.

When the asvmmwic
rectifier is defective, check whether magnetron, high voltage rectifier, high voltage sabre or
ment winding of the power transformer is shorted.

fila-

CARRY OUT 4R CHECKS
NOTE: FOR MEASUREMENT OF THE RESISTANCE OF THE RECTIFiE?, T?E !3&3-E?tzS

OF THE MEASURING INSTRUI\/IENT MUST HA,‘V/E ,A ‘Jc-JLTAGE AT LEAST E i’C~y.5

BECAUSE OTHERWISE AN iNFINITE RESISTANCE MIGHT BE SHC’\/VN iiN BGik
DIRECTIONS.

G’-x-“- --

4rOL3’d.‘,

D

HIGH VOLTAGE CAPACITOR TEST

CARRY OUT 30 CHECKS.

A.

B.

C.
D.

E.

F.

G.

Isolate the high voltage capacitor from the circuit.

Continuity check must be carried out with measuring instrument which is set io the highesT
resistance range.
A normal capacitor shows continuity for a short time (kick) and then a resisiance of about
10 MR after it has been charged.

A short-circuited capacitor shows continuity all the time.
An open capacitor constantly shows a resistance about 10 MQ because of its internal 10

MQ resistance.

When the internal wire is opened in the high voltage capacitor, the capacitor shows an in­finite resistance

The resistance across all the terminals and the chassis must be infinite when the capacitor

is normal.

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

CARRY OUT $J CHECKS

(RD82604J)

E

SWITCH TEST

CARRY OUT D 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

Plunger Operation

COM to NO

COM to NC

COM; Common terminal

Released

Open circuit

Short circuit

NO; Normally open terminal

Depressed

Short circuit

Open circuit

NC;

1

Normally closed terminal

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

CARRY OUT $J CHECKS.

11

R-5H53

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

F

MONITOR SWITCH TEST

CARRY OUT 3D CHECKS.

Before performing this test, make sure that the upper latch switch lower latch switch are oper­ating properly referring to the above Switch Test Procedure. Disconnect the wire leads from the
monttor switch (NC) terminal. Check the monitor switch operation by using the ohmmeter as

follows. .

BLACK WIRE

When the door is open the meter
should indicate a closed circuit. When

the monitor switch actuator is pushed

by a screw driver through the lower
latch hole on the front plate of the
oven cavity with the door opened (in

this condition the plunger of the

monitor switch is pushed in), the me-

ter should indicate an open circuit. If

Improper operation is indicated, re­place the defective switch. After test­ing the monitor switch, re-connect the

wrre lead to the monitor switch (NC)
terminal.

CARRY OUT 4R CHECKS

G

~~~~

TEMPERATURE FUSE TEST

CARRY OUT 30 CHECKS
A continuity check across the temperalure fuse termrnals should Indicate a closed circuit unless

the temperature of the temp. fuse reaches approxrmatelv

“r ‘I 5’ C. An open the temperature fuse
indicates overheating of the magnetron assembfv. If the temperature fuse indicates a open err­cuit, replace the temperature fuse and check for restricted air flow to the magnetron through the
opening In the chassis, especrally the air duci ant: fan motor.

CARRY OUT &R CHECKS

THERMAL CUT-OUT TEST

CARRY OUT 3D CHECKS

A continuity check across the thermal cut-out terminals sould indicate a closed circuit. If the
temperature of the steam duct reaches approximately 115°C the thermal cut-out opens. (This
thermal cut-out reset at below -2O’C) An open thermal cut-out indicates overheating of the oven
cavity. Check for restricted air flow to the magnetron through the opening in the chassis, espe­cially the air duct and fan motor.

CARRY OUT Q CHECKS
CAUTION IF THE THERMAL CUT-OUT INDICATES OPEN CIRCUIT, REPLACE THE THER-

MAL CUT-OUT.

I

BLOWN FUSE F M8A

CARRY OUT a CHECKS

1. If the fuse M8A is blown, there could be 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 M8A is blown, there could be short in the asymmetric rectifier 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.

3. If the fuse M8A is blown when the door is opened, check the upper latch switch, lower
latch switch monitor switch and monitor resistor.

12

R-5H53

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

If the fuse M8A is blown by incorrect door switching replace the defective switch(s) and

the fuse M8A.
CARRY OUT 4R CHECKS

CAUTION: Only replace fuse M8A with the correct value replacement.

J MONITOR RESISTOR TEST

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

Using an ohmmeter and set on a low range.
Check between the terminals of the monitor resistor. The resrstance of monitor is aporox. 0.8Q.
If incorrect readings are obtained, replace the monitor resistor and check the fuse ~Vl8A. upper

latch switch, lower iatch swatch and wire harness.
CARRY OUT @ CHECKS.

TOUCH CONTROL PANEL ASSEMBLY TEST

The touch control panel consists of circurts including semiconductors such as LSI ICs, etc
Therefore, unlike conventional microwave ovens, proper maintenance cannot be performec \mitl?
only a voltmeter and ohmmeter.

vided into two units, Control

In this service manual, the touch control panel assembly IS do-

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

scribed according to the symptoms indicated.

1. Key Unrt.
The foiiowing symptoms indrcate a defective key unrt. Replace the kev unit.
a) When touching the pads, a certain pad produces no signal at ail.
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 Panel
The following symptoms indicate a defective control unit. Replace the controi unit.
2-l tn 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 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.

d) Proper temperature measurement is not obtained.

L

EASY DEFROST TEST

(1) Place one cup of water in the center of the turntable tray in the oven cavity.
(2) Close the door, touch the “EASY DEFROST” pad.

(3) Touch the number 5 pad to enter weight (0.5 Kg. is set).
(4) Touch “START” pad. Now the oven is in EASY DEFROST cooking condition.
(5) The oven will operate as follows.

1 ST STAGE

2ND STAGE

LEVEL

TIME

LEVEL

TIME

100?6

75sec.

50%

125sec.

3RD STAGE

LEVEL

TIME

0%

400sec.

4TH STAGE

LEVEL

TIME

30% 160sec.

13

R-5H53

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER COMPONENT TEST

(6) If improper operation is indicated, the control unit is probably defective and should be

checked.

M RELAY TEST

Remove the outer case and check voltage between Pin Nos. 1 and 3 of the 3-pin connector (A)

on the control unit with an A.C. voltmeter. The meter should indicate 240 volts, if not check oven

circuit.

RYI and RYZ Relay Test

These relays are operated by D.C. voltage.

Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.

DC. voltage indicated

. . . . . . . . . . Defective relay.

DC. voltage not indicated . . . . . . ..Check diode which is connected to the relay coil. If diode is

good, control unit is defective.

I

RELAY SYMBOL

OPERATIONAL CONNECTED COMPONENTS

VO LTAG E

I

RYI Approx. 13 V.D.C.
RY2

ADDrox 14 V. D C.

Oven lamp/Turntabie motor/Cooling fan motor
Power transformer

N

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 trou­bieshooting guide given below for repair.

Problem. POWER ON, indicator does not light up.

__--____ ---__

ZTEPC

Lj i .

OCC!JRRENCE CAL’SE OR CORRECTION ---__

7 ‘TL -

-____

I I!e rated vo!tage IS no: apolled to POWER terminal

Check supply voltage and oven main unit

si CPU connector (CN-A)

____--___- _

-,

The rated voltage IS spoiled to pr!mar\ srde of power

Power transformer or secondary cIrcuIt defective.

transfcrmer Check and repair

~--____

3nli ;latterr a; “a’ IS broken

‘inser: lumper wire Jl and solder.

Pa:reri- a: ’ 2”

apd “0” are broker

*insert the coil RCILF2003YAZZ between “c” and

“d”

hJC3T[ L

4+ tpe rime of tpese repairs make a vlsua! IP-
spect’on of the varlstor fol burning damage
and examine the transformer with tester for the
presence of [aver shor?-clrcult (check primary
coil resisrance)
It anv abnormal conaittoT? IS detected, replace
the defective parts.

0

AH SENSOR TEST

Checking the initial sensor cooking condition

(1 ) The oven should be plugged in at least five minutes before sensor cooking.
(2) Room temperature should not exceed 95”F(35”C).
(3) The unit should not be installed in any area where heat and steam are generated. The unit

should not be installed, for example, next to a conventional surface unit. Refer to the

“INSTALLATION Instructions”.

(4) Exhaust vents are provided on the back of the unit for proper cooling and air flow in the

cavity.To permit adequate ventilation, be sure to install so as not to block these vents.
There should be some space for air circulation.

14

R-5H53

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER

COMPONENT TEST

(5) Be sure the exterior of the cooking container and the interior of the oven are dry. Wipe off

any moisture with a dry cloth or paper towel.

(6) The Sensor works with food at normal storage temperature.For example, chicken pieces

would be at refrigerator temperature and canned soup at room temperature.

(7) Avoid using aerosol sprays or cleaning solvents near the oven while using Sensor settings.

The sensor will detect the vapor given of by the spray and turn off before food is properly
cooked.

(8) After about 41 minutes if the sensor has not detected the vapor of the food, ERROR will

appear and the oven will shut off.

Water load cooking test

Make sure the oven has been plugged in at least five minutes before checking sensor cook op-

eration. The cabinet should be installed and screws tightened.

(1) Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring cup.
(2) Place the container on the center of tray in the oven cavity.
(3) Close the door.
(4) Touch SENSOR COOK FRESH pad and number pad 8. Now, the oven is in the sensor

cooking condition and SC-8 will appear in the display.

(5) Touch Start pad.The oven will operate for the first 16 seconds, without generating micro-

wave energy.

NOTE: ERROR will appear if the door is opend or STOP/CLEAR pad is touched during first stage

of sensor cooking.

(6) After approximately 16 seconds, microwave energy is produced, oven should turn off when

water is boiling (bubling).

If the oven does not turn off, replace the AH sensor or check the control unit, refer to explanation

below:

TESTING METHOD FOR AH SENSOR AND/OR CONTROL UNIT

To determine if the sensor is defective, the simplest method is to replace it with a new replacement
sensor.

(1) Disconnect oven from power supply and remove outer case.
(2) Discharge the high voltage capacitor.
(3) Remove the AH sensor.
(4) Install the new AH sensor.
(5) Re-install the outer case.
(6) Reconnect the oven to the power supply and check the sensor cook operation proceed as

follows:
6-l. Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring

cup.
6-2. Place the container on the center of tray in the oven cavity.
6-3. Close the door.
6-4. Touch SENSOR COOK FRESH pad and number 8 pad.
6-5. Touch Start pad. The control panel is in automatic Sensor operation.
6-6. The oven will turn off automatically when the water is boiling (bubbling).

If new sensor dose not operate properly, the problem is with the control unit.

CHECKING CONTROL UNIT

(1) Disconnect oven from power supply and remove outer case.
(2) Discharge the high voltage capacitor.
(3) Disconnect the wire leads from the cook relay.
(4) Disconnect the sensor connector that is mounted to lower portion of control panel.
(5) Then connect the dummy resistor circuit (see fig.) to the sensor connector of control panel.
(6) Reconnect the oven to the power supply and check the sensor cook operation proceed as

follows:
6-1. Touch SENSOR COOK FRESH pad and number 8 pad.
6-2. The control panel is in the sensor cooking operation.
6-3. After approximately 20 seconds, push plunger of select switch.

This condition is same as judgement by AH sensor.
6-4. After approximately 3 seconds, cooking operation turns off, an audible signal will

sound, and the display will then revert to the time of day.

15

R-5H53

TEST PROCEDURES (CONT’D)

PROCEDURE

LETTER COMPONENT TEST

If the above is not the case, the control unit is probably defective.
If the above is proper, the AH sensor is probably defective.

PLUNGER

I

To Connector (FI
on Control Unit

Rl,R2 : 22R &- 1% 1 i2W

R3:lOkQ + 5% 1/4W

R4 : 1 MCI f 5% 1/4W

NC
NO

F-l - m

F-Z- rc

Sensor Dummy Resistor Circuit

OUTLINE OF TOUCH CONTROL PANEL

ihe touch control section consists of the foliowing

units as shown rn the touch control panei circuit.

iI> Key Unit
(2) Contra! Unit

Tne prrnctpal functions of these units and the signals

communrcated among them are explained beiow.

Key Unit

The ke\f unii is com2osec of a matrix. signals generated
: r:

the iSI are sent T#-

; e

P63,P04,P36,PG7, p: 7 P: fBnrP< Jey

unit

thrnugh

LYnen a key pat !s roscned, a signal is c.ompieted

through

:ne kev dni: and passed oack to the LSi

:aroUgh zs-;-?Iz 12 i>erf5:7- the funcirc>T :r,a: n/as ye­ouesied.

Control Unit

Zontroi iintt cons:sis .of iSi. power source circuit,
synchronizrng signal crrcurt. ACL circuit, buzzer circurt,
temperature measurement clrcu;:,

reheat sensor cfrcuit

and Indicator circuit.
‘I) LSI

This LSI controls tne

temperature measurement
signai. reheat sensor signal. key strobe signal. relay
driving signai for oven function and indicator sig­nal.

2) Power Source Circuit

This circuit generates
contra! unit.

voltage necessary in the

Symbol Voltage Application

----­VC

-5.ov

VP

LSI (ICI), ACL circuit

-26V

Fluorescent display tube : Grid

VF-

3Vac

and anode voltage

Filament of fluorescent display

VF+

----

tube
(VF- to VF-C voltage)

3)

4)

5)

fi)

71

8)

9)

Synchronizing Signal Circuit

The power source synchronizing signal is avaiiable

in order to compose a basic ‘standard time in the
clock circuit.

It accompanies a very smali error because it works

on commercral frequency.

ACL Circuit

A. circuit to generate a signal which resets the LSI

to ;he inltiai state when power is supplred.

&uzzer Circuit

The buzzer responds to signais from the LSI to
emrt noticing sounds (key touch sound and com-

aletion sound).

(RD9; AA1 U/

Reheat Sensor Circuit

This ctrcuit detects moisture of a food which is
cooking,to allow its automatic cooking.

Stop Switch

A switch to “tell” the LS! 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.

16

R-5H53

LSl(lZA393DR)

DESCRIPTION OF LSI

The I/O signals of the LSl(lZA393DR) are detailed in the following table.

PIN NO. 1

L

SIGNAL VREF

I

l/O

IN

Reference voltage input terminal.

A reference voltage appiied to the A/D converter In the LSI. Connected to GND (OV)

RD(:Ij<Aji

PIN NO.

2-4

-__-

1 SIGNAL IN7-IN5

I

I/O

IN

Heating constant compensation terminal.

+?),G>.-ji:_it

PIN NO 5

-____-- -.--__- ~--__--- ~~

-~

_i

SIGNAL INA

__- --~- - ----~~~ ~~_. ~~ I ~

It 0 / IN

Terminal to change functions according to the model.

Signal in accordance with the model in operation is applied to se? up its function

i-‘

_ ,-A -2

1

_~ >-- ._/

PIN NO. 6 SIGNAL

i rd3

i 0

IN

Input signal which communicates the door open!‘close information to LSI.

Door closed; “H” level signal! OV). / Door opened: “L” level signal(-5V)

- ---

,. L -’

^L ; ‘j

PIN NO. 7

-~._~ .r7YzILS’“!!!~L~ - ‘f“” ~~ - I i cz 129 ~--

Connected to GND.

PIN NO. 8

.---L.

SIGNAL

\r\jl

I-

i ,P

I

2

j p.;

AH sensor input.

This input is an anaiog input ierm;nai iron -.he AH sc?nsor sirc,~,:, 3flG ;~Fc~c:& +:

y--q 1 3

y

converter built into the LSI.

‘i’,.. ,c 1 -

t-u__r~-

PIN NO. 9

~___

~~ .__7z!G!!lpIN0 .~ ~~_- ~ _ -T=-- IN

Used for initial balancing of the bridge circuit(absoiu:e humidity sensor): This input !s an anal05 *!~i=,-: rermlnai

from the AH sensor circuit, and connected to the A D converter burit into the LS;

PIN NO. IO-14

1

SIGNAL P47-P43

~__-- __.- -~-~-_.-------~-~

L

i/O

OUT

-~ _ ~~

Used for initial balancing of the bridge circuit(absolute humidity sensor)

PIN NO.

15-l 7

~_____.

Terminal not used.

SIGNAL

P42- P40

110 OUT

__- I

PIN NO. 18

1 SIGNAL P37

1

l/O

OUT

---____

Oven lamp driving siqnal.

To turn on and off shut-off relay( RYI ).

I

20 muc

r

The square waveform voltage is delivered to the ‘- - - -

-+

relay( RYl ) driving circuit and relay (RY2) control circuit.

L-L

PIN NO.

/ 19

1 SIGNAL

P36

I

I/O

OUT

Terminal not used.
PIN NO.; 20

1 SIGNAL

P35

Maclnetron high-voltage circuit driving signal.

To turn on and off the cook relay(RY2).

l/O

OUT

I

--

In high operation, the signals holds “L” level during

H’GH ?TT____
microwave cooking and “H” level while not cooking, In
other cooking modes (MED HIGH, MED, MED LOW,

LOW) the signal turns to “H” level and “L” level in repe-

MED “l”qLm

tition according to the power level.

ME0

17

R-5H53

PIN NO.

/ 35

1 SIGNAL R2

I

I/O

/ IN

Siqnal similar to R3.

When any one of G-10 line keys on key matrix is touched, a corresponding signal will be input into R2.

(RD93CA8U)

PIN NO. 36

1 SIGNAL Rl

I

I/O

I IN

Signal similar to R3.

When any one of G-9 line keys on key matrix is touched, a corresponding signal will be input into RI.

(RD93CABU)

PIN NO. 37

RO

1 SIGNAL

I

I/O

IN

-~-____~

Siqnal similar to R3.

When any one of G-8 line keys on key matrix is touched, a corresponding signal will be input into RO.

(RD93CABUi

PIN NO. 38

__-

______ ~___

VP

~~ 1 SiGNAL

I

l/O

IN

Anode (seqment) of Fiuorescent Display light-up voltaqe: -26V.

Vp voltage of power source circuit input.

(RD93GABlJI

PIN NO. 39-40

Terminal not used.

L

SiGNAL P17-PI6

-_lL!!!LOUT!

PIN NO. 41

SIGNAL PI 5

-__

___-

Seqment data siqnais.

The relationship between signals and indicators are as foilows:

I

I/O

OUT

_____-

Signal Segment

Pl 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . .

..i. . . . . . . LB

PI 4... . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . UB

P13...

. . . . . . . . . . . . . . . . . . . . . . . . . . . . ~ . . . . . .

k

P12 ..,........................

. . . . . . . . . . ‘ . . . j

PII. . . . . . . . . ..*..............~...I.........L,,

I

,

PI0 . . . . . . . . . . . .

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

.I.

h

PO7 . . . . . . . . . . . . . . . . . . . . .

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

g

Signai

PC6 . .

. . . . , .

Segment

s..........,.

f

PO5

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

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

PO4 ............... ...................

:

PO3

., . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . c

PO2 . ..t........... ~ ./.,....................... b

PO?

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

a

moq 1-i

JxrKI:z.

-2w.

PIN NO. 42 1 SIGNAL

PI4

I

I/O

OUT

Seqment data siqnil.

Signal similar to PI 5.

Key strobe siqnai.

Signal applied to touch-key section. A pulse signal is input to RO-R3 terminal

while one of G-l line keys on key matrix is touched.

(RD939A3U1

PIN NO.

i 43

1 SIGNAL PI3

I

I/O

/ OUT

Seqment data siqnal. Signal similar to PI 5.

(RD939AZUl

PIN NO.

/ 44

Segment data signal.

Signal similar to PI 5.

PIN NO. ; 45

Seqment data signal.

Signal similar to PI 5.

SIGNAL 1 PI2

I

l/O

j OUT

Kev strobe siqnal.

Signal applied to touch-key section. A pulse signal is input to RO-R3 terminal

while one of G-2 line keys on key matrix is touched.

(RD939A3U)

SIGNAL

PI 1

I

l/O

/ OUT

Kev strobe siqnal.

Signal applied to touch-key section. A pulse signal is input to RO-R3 terminal
while one of G-3 line keys on kev matrix is touched.

(RD939A3U)

PIN NO.

/ 46

1 SIGNAL

PI0

l/O

/ OUT

Seament data siqnal. Signal similar to PI 5.

I

PIN NO.

/ 47

1 SIGNAL

PO7

Seqment data siqnal.

Kev strobe siqnal.

(RD939AZU)

I

I/O

I OUT

Signal similar to PI 5. Signal applied to touch-key section. A pulse signal is input to RO-R3 terminal

while one of G-4 line keys on key matrix is touched.

(RD939A3U)

19

R-5H53

PIN NO, 48

_____

Segment data signal.

Signal similar to PI 5.

PIN NO. 49

SIGNAL : PO6

I

I/O

OUT

Kev strobe signal.

Signal applied to touch-key section. A pulse signal is input to RO-R3 terminal
while one of G-5 line keys on key matrix is touched.

(RD939A3U)

1 SIGNAL PO5

I

I/O

j OUT

Segment data signal. Signal similar to PI 5.

(RG939A2U)

PIN NO.

50

1 SIGNAL I PO4

I

I/O

1 OUT

Segment data signal.

Signal similar to PI 5.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to RO-R3 terminal
while one of G-6 line keys on key matrix is touched.

(RDS39A3Uj

PIN NO. 51

-___--.-

1 SIGNAL / PO3

1 l/O i OUT

Segment data signal. Kev strobe signal.

Signal similar to PI 5.

Signal applied to touch-key section. A pulse signal is input to RO-R3 terminal
while one of G-7 line keys on key matrix is touched.

(RD939A3U)

PIN NO. ’ 52-53 1 SIGNAL 1 PO2-PO1

I

l/O I OUT

Segment data signal. Signal similar to PI 5.

(RD939A2U)

PIN NO. 54

- ---_____

1 SIGNAL ’ PO0

I

i/O

OUT

Diqit selection signal.

The relation between digit signal and digit are as follows:

Digit signal

Digit

P23

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

1 st.

334 -_

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd.

“25 . . . . . . . . . . ..~.,....~................................,.....,

3rd.

PZE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4th.

2?7

LI

pa?;

. . 1 . . ..t... . . . . . . . . . . . .

5th.

., ,

,.. . . . . . . . . . . . . . . . . . . . . . . . . . .._

6th.

P23

P24 -.-J-L---

P26 n

r<?r-,sii\’

ccle [sti!se

ts output in every 13 period, and

7 7, I-

‘p‘.+ L ‘is one gr~ci oi the Fluorescent Display.

P26 e--km.-

P27 --A!--

i-l

-----* (1)10

DIN NO

55-59

SIGNAL P27- P23

I/O OUT

----- -__

I

Binit selection sianal. Signal similar to PI 5.

C RD938A2U)

PIN NO

60-61

SIGNAL

P22- P21

i/o

OUT

Terminal not used.

___~

I

PIN NO. 62

Connected to GND.

1 SIGNAL P20

I

I/O

/ OUT

PIN NO.

63/64

~____-~

Connected to GND.

SIGNAL

AVCC,‘VSS

I

I/O

1 IN

20

R-5H53

ABSOLUTE HUMIDITY SENSOR ClRCUlT

(1) Structure of Absolute Humidity Sensor

The absolute humidity sensor includes two
thermistors as shown in the illustration. One
thermister is housed in the closed vessel filled with
dry air while another is in the open vessel. Each
sensor is provided with the protective cover made
of metal mesh to be protected from the externai
airflow.

SeMmg port Sensing pan

(2) Operational Principle of Absolute Humidity

Sensor

The figure below shows the basic structure of an
absolute humidity sensor.

A bridge circuit is
formed by two thermistors and two resistors !X
and R2).
The output of the bridge circuit is to be amplified
by the operational amplifier.

Each thermistor is supplied with a current to keep

itself heated at about 150°C (302°F) and :he re-

sultant heat is dissipated in the air and if the two
thermistors are placed in different humidity conai­tions they show different degrees of hea:
conductivity leading to a potential difference be­tween them causing an output voltage from the
bridge circuit, the intensity of which is increased
as the absolute humidity of the air increases. Since
the output is very minute, it will be amplified by the
operational amplifier.

~~~~~ :‘~er~

Absolute humidity (g/m’ I

(3)Detector Circuite of Absolute Humidity

Sensor

This detector circuit is used to detect the output
voltage of the absolute humidity circuit to allow the

LSl to control the sensor cooking of the unit.

When the unit is set in the sensor cooking mode,

16 seconds later the detector circuit starts to func-

tion and the LSI observes the initial voltage avail-

able at its IN1 terminal. With this voltage given, the
switches SW1 to SW5 in the LSI are turned on in
such a way as to change the resistance values in
parallel with R-l.
Changing the resistance values results in that there
is the same potential at both F-3 terminal of the
absolute humidity sensor and IN0 terminal of the
LSI. The voltage of IN1 terminal will indicate about

-2.5V. This initial balancing is set up about 16
seconds after the unit is put in the Sensor Cooking

mode.
As the sensor cookmg proceeds, the food IS heated
to generate moisture by which the resistance bal­ance of the bridge circuit is deviated to increase the
voltage available at IN? terminal of the LSi. Then
the LSI observes that voltage at IN1 terminal and
compares it *with its initial value, and when the
comparison rate reaches the preset value (fixed for
each menu to be cooked), the LSI causes the unit
to stop sensor cooking; thereafter, the unrt gets in
the next necessary operation automatically
When the LSi starts to derect rhe initial voltage at

tN1 terminal 16 seconds after Ihe gnit has been put

.

in the Sensor

Cooking mode, rf :T ;s tmpossrbie tc

take a baiance of ine bridge c!rcuit due to Qiscon-

nection of the absolute humrdity sensor, ERROR

will reappear on the ciispiay and the cxk:ng is

stopped.

Absolute humidity senscr ‘t--ll?

;‘I btil

vc:-3v

I

SW,

PO&+--&
P-/Q2
P452Jj

P44-/

,Tq

21

SERVICING

I. Precautions for Handling Electronic

Components

This unit uses CMOS LSI in the integral part of the
circuits. When handling these parts, the following
precautions should be strictly followed.
CMOS LSI have extremely high impedance at its
input and output terminals. For this reason, it is
easily influenced by the surrounding high voltage
power source, static electricity charge in clothes,
etc,and sometimes it is not fully protected by the
built-in protection circuit.

in order to protect CMOS LSI.

1) When storing and transporting, thoroughly
wrap them in aiuminum foil.
Also wrap all 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.

1M.Q

2. Shapes of Electronic Components

9

2. Servicing of Touch CantroE Panel

$;‘e describe the procedures to permit servicing of
tne touch

control . panel of ?he microwave oven and
:ne precautions you must take when doing so.
To perform the servicing, power to the touch con­tro! panel is availabie either from the power line of
the oven itself or from an external power source.

(‘I) Servicing the touch control panef with

power supply of the oven:

CAUTION:

-l-HE HIGH VOLTAGE TRANSFORMER OF
THE MlCRQWAVE OVEN IS STILL LIVE

DURING SERVICING AND PRESENTS A
HAZARD.

Therefore, when checking the performance of

the touch control panel, put the outer cabinet

on the oven to avoid touching the high voltage

transformer,

or unplug the primary terminal

(connector) of the high voltage transformer to

turn it off; the end of such connector must 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 it­self is so short that the two can’t be separated.

For those models, check and repair ail the

controls (sensor-related ones included) of the
touch control panel while keeping it connected
to the oven.

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

tween the touch control panel and the oven

proper is long enough that they may be sepa-

rated from each other. For those models,
therefore, it is possible 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 door
sensing switch (on PWB) of the touch control

panel with a jumper, which brings about an
operational state that is equivalent to the oven
door being closed.
As for the sensor-related controls of the touch
control panel, checking them is possible if
dummy resistor(s) with resistance equal to that

of the controls are used.

(2) Servicing the touch control panel with

power supply from an external power
source:

Disconnect the touch control panel completely
from the oven properand short both ends of
the door sensing switch (on PWB) of the touch
control panel,which brings about an opera­tional state that is equivalent to the oven door
being closed.

Connect an external power
source to the power input terminal of the touch
control panel, then it is possible to check and
repair the controls of the touch control panel;

r; is alsc possible to check the sensor-related
controls of the touch control panel by using the
dummy resistor(s).

4, Servicing Toois

Toois

required to service the touch control panel

assem b!y

.’

: \ Sctdering rron: 30W

[II is recommended to use a soidering iron with a

grounding terminal.)

2) Oscitloscope:

Single beam, frequency range:
DC - 10Mti.z type or more ad­vanced model.

3: Others:

Hand tools

5. Other Precautions

7) Before turning on the power source of the
control unit, remove the aiuminum foil applied
for preventing static electricity.

2) Connect the connector of the key unit to the
control unit being sure that the lead wires are
not twisted.

3) After aiuminum foil is removed, be careful 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, making sure that ail connections are
tight.

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

22

R-5H53

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

WARNING: Avoid possible exposure to microwave energy.

Please follow the instructions below

before ooeratina the oven.

1. CARRY OUT 3D CHECKS.

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 heads to rise, it is then possible to hear a
“click” as the door switches operate.)

3. Visually check the door and cavity face plate for
damage (dents, cracks, signs of arcing etc.).

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

3. The door gasket or seal is damaged.

4. The door is bent or warped.

5. There are defective parts in the door inter!ock sys­tern.

6. There are defective parts in the microwave generat­ing and transmission assembly

7. There is visible damage to the oven:.

Carry out any remedial work that is necessary before

Do not operate the oven:

operating the oven.

1. Without the RF gasket (Magnerron’f.

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

2. if the wave guide or oven cavity are net !nlac:

ditions exist;

3. If the door is not closed.

I. Door does not close firmly.

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

Please refer to ‘OVEN PARTS, CABINET PARTS, DOOR PARTS’, when carrying out any of the $oilowing removal
procedures:

9

;A,pp”,’ ;

HIGH VOLTAGE COMPONENTS REMOVAL

(HIGH VOLTAGE CAPACITOR AND HIGH VOLTAGE RECTIFIER ASSEMBLY!

To remove the comoonents. oroceed as foilows.

::

3.

4.

5.

CARRY OUT & CHECKS.

Remove one (1) screw holding capacitor hoider to

oven unit.

Remove one (I ) screw holding earth side termfnai

of rectifier ass’y and remove capacitor holder.

Disconnect wire leads and terminal of high voltage
rectifier assembly from high voltage capacitor.
Now, high voltage rectifier assembly can be re­moved.

TRANS. -

MAG. f-

TRANS. -

Shon

protector

i

CAUTION: WHEN REPLACING HIGH VOLTAGE

Sllicon /

Aoctifior

RECTIFIER ASSEMBLY, EARTH SIDE

4

TERMINAL

MUST BE SECURED

FIRMLY WITH A EARTHING SCREW.

1.

2.

3.

4,

1.

2.

3.

MAGNETRON REMOVAL

CARRY OUT 3D CHECKS.
Disconnect wire leads from magnetron.

5. First lower the right-hand side of the magnetron
through magnetron duct.

Carefully loosen four (4) screws holding magnetron

7. Magnetron is now free.

to waveguide flange while supporting the

magnetron from below.

CAUTION:

WHEN REPLACING THE MAGNETRON,

Lower magnetron until antenna is clear of the

BE SURE THE R.F. GASKET IS IN

waveguide.

PLACE AND MAGNETRON MOUNTING

SCREWS ARE TIGHTENED SECURELY.

TURNTABLE MOTOR REMOVAL

CARRY OUT 3D CHECKS.

Open the door and remove turntable and roller stay.
Turn oven unit upside down and remove two (2)
screws holding turntable motor cover to bottom
side of oven cavity and base cabinet right.

4. Disconnect wire leads from turntable motor.

5. Remove two(2) screws holding turntable motor and
pull it out, at this time O-RING attaching with mo-

tor is removed.

23

TURNTABLE COUPLING REMOVAL

1. Remove turntable motor, refer to “Turntable Motor
Removal”.

2. Remove turntable coupling following in order on
illustration.

TURN TABLE

COUPLING

BOTTOM
OVEN CAVITY

T.T. MOTOR

ANGLE

‘O-RING

Turntable Coupling

COOLING FAN MOTOR REMOVAL

1. CARRY OUT 3D CHECKS.

2. Remove wire leads from cooling fan duct.

3. Remove two (2) screws and tab on fan duct hold­ing to top oven cavity.

4. Pull fan blade out of cooling fan motor.

5. Remove two (2) screws and two (2) nuts holding
fan motor.

6. Now cooling fan motor is free.

CONTROL PANEL ASSEMBLY AND COMPONENTS REMOVAL

The complete control panel should be removed for re-

placement of the components.

To remove the control panel, proceed as follows:

1. CARRY OUT 3D CHECKS.

2. Disconnect (A) and (b) connectors from the control
unit.

3. Remove one (1) screw holding the control panel
frame to the oven cavity front flange.

4. Lift up the control panel frame to free the panel
hooks from the bottom opening of back piate.

5. Pull the control panel forward.

Replacement of individual component is as follows:

CONTROL UNIT AND/OR PANEL FRAME

7. Push the holder of 12-pin connector (D) inward
and then pull it

2, Remove the flat cable of key from the 12-pin con-

nector (G) .;

3 Remove the five (5) screws holding the control unit

to the pane! frame.

4. Panei frame and contra! unrt are now free,, separate

them

UPPER LATCH SWITCH AND MONITOR SWITCH REMOVAL

1 CARRY OUT 3D CHECKS.
2 Disconnen- Lo wire leads from switches.

4 Remove upper latch hook from fiange by moving it

downward

3. Remove one (1 > screw holding the upper latch

5. To remove the switch from upper latch hook, push

hook to the oven cavity flange.

outward two i:2j;

retaining tabs holding individual

switch in place.

LOWER LATCH SWITCH, STOP SWfTCH AND LATCH SWITCH REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect wireleads from switches.

4. Remove lower latch hook from flange by moving it
downward.

3. Remove one (I) screw holding the lower latch
hook to the oven cavity flange.

5. Push outward two (2) retaining tabs holding stop
switch in place.

6. Now switches are free.

UPPER/LOWER LATCH SWITCHES, STOP SWITCH AND

MONITOR SWITCH ADJUSTMENT

If the upper and lower latch switches, latch switch,
stop switch and monitor switch do not operate prop­erly due to a mis-adjustment, the following adjustment
should be made.

1. Loosen the one (1) screw holding the upper latch
hook to the oven cavity front flange and the one (1)

screw holding the lower latch hook to the same
flange.

2. With door closed, adjust lower latch hook by mov­ing it back and forth and then adjust the upper latch
hook by moving it back and forth, or up and down.
In and out play of the door allowed by the upper

and lower latch hooks should be less than 0.5 mm.
The vertical position of the upper latch hook should

be placed where the upper latch switch and monitor
switch have activated with the door closed. Vertical
adjustment of the lower latch hook is not possible.

24

-

R-5H53

3. Secure the screws with washers firmly.

4. Make sure of the upper latch switch operation. If
the upper latch switch has not activated with the
door closed, loose one (1) screw holding upper

iatch hook to oven cavity front flange and adjust
upper latch hook position.

HOOU

MONITOR
SWITCH

UPPER
LATCH

After adjustment, make sure of the following:

1. In and out play of door remains less than 0.5 mm
when latched position. First check upper latch hook
position, pushing and pulling upper portion of door
toward the oven face. Then check the lower latch
hook position. pushing and pulling lower portion
of door toward the oven face. Both results (plays
of the door) should be less than 0.5mm.

2. The upper, lower latch and latch switches interruot
the circurt before the door can be opened.

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

SWITCH

LCWER
LATCH
HOOK

STOP

SWITCH
LOWER

LATCH

SWITCH (INSIDE ONE)
LATCH

WITCH (OUTSIDE ONE)

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

Figure C-7. Latch Switch Adjustment

DOOR REPLACEMENT AND ADJUSTMENT

DOOR REPLACEi\/lENi

1. CARRY OUT 30 CHECKS.

2. Remove two (2) screws hoidtng lower oven hinge.

3. Remove the lower oven hinge from ihe door,

4. Remove door assembiy from upper oven hmge.

5. On re-installing door, insert the upper oven hinge
into the door hinge pin.

6. Insert the lower oven hinge into the door hrnge pin.
Then while holding the door in place secure the
lower oven hinge firmly with the two (2) mounting
screws.

7. Make sure door is parallel with oven face lines (left
and upper side lines) and the door latch heads pass

through the latch holes correctly.

Note: After any service to the door;
(A) Make sure that the upper latch switch, lower

latch switch and latch switch are operating
properly.

4. Re-install outer case ant cneck ior mtc:owa:fe
leakage around the door with an approved ,T-I~c:o-
wave survey meter.

(Refer to Microwave Measurement Procedure.;

Note: The door on a micro*vvave oven is designee to

act as an electronic seal preventrng the leakage
of ;nicrowave energy from the oven cavity during
the cook cycle.
that

This function does not require

the door be air-tight,

moisture

(condensation)-tight or light-tight. Therefore,
the occasional appearance of moisture, light or
the sensing of gentle warm air movement around
the oven door is not abnormal and do not of
themselves, indicate a leakage of microwave en­ergy from the oven cavity. If such were the case,
your oven could not be equipped with a vent,
the very purpose of which is to exhaust the
vapor-laden air from the oven cavity.

(B)

(Refer to chapter “Test Procedures”.).
An approved microwave survey meter should
be used to assure compliance with proper
microwave

radiation

emission limitation

standards.

DOOR ADJUSTMENT

The door can be adjusted by keeping the screws of
each hinge loose.

After adjustment, make sure of the following :

1. Door latch heads smoothly catch, the latch hooks
through the latch holes, and also the each latch

head goes through the center of the latch hole.

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 to­ward the cavity face plate.

Figure C-2. Door Replacement and Adjustment

25

R-5H53

LATCH HEAD REMOVAL AND DOOR DISASSEMBLY

Remove the door assembly, refer to item 1, through 5,

of H Door Replacement”.

1.

2.

3.

4.

5.

6.

Place the door assembly on a soft cloth with facing
UP.

lnsert an iron plate (thickness of about 0.5mm) to
the gap between the choke cover and the corner
portion of door panel as shown figure to free the
engaging parts.

Lift up the choke cover.

Now the choke cover is free from the door panel.

Remove the latch spring from the door panel.

Pushing up the latch head, it is now free from door
panel.

R

n

FLAT TVCE
EcnLw.oaIVEa

.-

IiF

WOlECl l v TAPE

Latch Head Remove and Door Disassembly

.

POSITIVE LOCK@

CONNECTOR (NO-CASE TYPE) REMOVAL

Push the lever of positive lock” connector, Pull down

on the positive lock” connector.

Termicul

CAUTION: WHEN

YOU CONNECTING THE

POSIT-WE LOCK@ CONNECTORS TO
THE TERMINALS,

INSTALL THE

POSITWE LOCK@ SO THAT THE LE-
VER FACES YOU

Figure C-3. Positive lock @ connector

26

R-5H53

MICROWAVE

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 bookiet.
Important:
Survey instruments that comply with the requrre­ment for instrumentations as prescribed by the per-

formance standard for mrcrowave ovens must be

used for testing.
Recommended instruments are:
NARDA 8100
NAR DA 8200
HOLADAY HI 1500

SIMPSON 380M

2. Place the oven tray into the oven cavity.

3. Place the load of 275&l 5ml of swater 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

.

MEASUREMENT

an electrically non-conductive material such as
glass or plastic.
The placing of this standard load in the oven is im­portant not only to protect the oven, but also to in­sure that any leakage is measured accurately.
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.
Move the probe slowly (not faster that 2.5cm/sec.)

along the gap.
The microwave radiation emission should be meas­ured at any point of 5cm or more from the external
surface of the oven.

Microwave leakage measurement at 5 cm dis-

tance

(RDEii’3EU)

27

R-5H53

____

---___

_.------- --

SCEMATIC

NOTE: CONDITION OF OVEN

1. DOOR CLOSED.

2 CLOCK APPEARS ON DISPLAY.

l-

AH SENSOR

- -1

3 ‘,,i

Id

I

Jl

iJ:j

I

---

w

L.-i

8
I4 ?

+-sj

o-

E=

$

rii

r%

ZE

Figure O-1. Oven Schematic-OFF Condition

SCEMATIC
NOTE, CONDITION OF C)VEN
1 DOOR CLOSED
2 COgKiNG TIIME PROGRAMMED
3 VARlABLE COOKING CONTROL “hIGH”
i START

%I2 ‘O’JCHIED

SCEMATIC

NOTE: CONDITION OF OVEN

1. DOOR CLOSED.
?

“FRESH” OR “FROZEN” PAD TOUCHED
5 DESIRED SENSOR SETTING NO TOUCHED
4 START PAD TOLlCHED

_____ --

I
L

$-+

0
aa
i-0
IzL

g
2E

r---

r-1 I

L.3

i----J

8

84

z!

Figure O-2. Oven Schematic-Cooking or Sensor Cooking Condition

28

I

I

c)

I

n

I

m

0 0

m

--_____

---

_---------.- .-... - .-- --. I

I b

.- _____

CN-E

II

AH sensor assembly

55

MAIN Touch control unit

CN-E

0

FAN MOTOR

r---j BLK [

7

1

4

MONITOR
SWITCH

UPPER

1

I

/

FUSE MBA 6
FUSE HOLDER

0

BLU j--+

CN-

WHT j--

1/

-----d

H.V.C.

WHT )--

-

WHT k

-

I--

II ----

-

4

CAB SIDE

-

- RED

CN-A

-EEI--

-

-

,

1

-

I-

q UUO~
1 3 !i 7

1

E4

@I

OVEN
THERMAL

::MP

---f PNK

CUT-OUT

FUSE

NO

GRN )--

t

OVEN CAVITY SIc)E

-a

- COM

Y

STOP

E

SWITCH

I

2

+

‘%

t

I

t

IU

-------- .-- -----_ __ _

CN-B

CAHTEII- 1

-

I

I

lH.V.RECTIFIER

~~ -~

P4~t.e l.@is Positive lock*connector.

T1.YELLOW lead wire may be Pink.

a

Figure S-l. Pictorial Diagram

-.
I

--

---

0

- ---- -.--. -_ .- _I .__

.-

n

m

0 I

----- ---- -------.-.---

C) m

---Y-u YI**-“l.““” 1 LI1”-yyIIY”

b

-II_-

L 1

R-5H53

I I ,%
I

I I

: i-.i

5

g$

I

L

>

;p g

::

%

1

I

*fZ

1 1 WV 1 “‘I 1

.”

SO

‘W

~

s

t- 0

dp”‘“F2

j IJ

*SE,dOOOl 13

*

?i gi

65, Zi

;I -

h

i ---i

1

2

3 4 5

6

30

1

2

3

4

5

6

Cll

Figure S-3. Printed Wiring Board

I

1

I 2 3

I

I

4

I

5

6

31

MH53

PARTS LIST

Note : The voltage supplied to the parts n*r are greater than 25OV.

REF. NO. 1 PART NO.

DESCRIPTION

1 O’TY ICODE

ELECTRICAL PARTS

*
*
*
*

l- 1

QACCAA018WREO Power supply cord

1

AQ

;I ;

QFS-CAOlOWREO Fuse M8A

AE

QFSHDA002WREO Fuse holder

i AE

l- 4 QFS-TAOlOWREO Temperature fuse 115°C

1 AG

I.- 5 QSOCLAOOlWREO Oven lamp socket

1

AK

l- 6 QSW-MA007WREO Upper lower latch switches, stop switch

3 AE

(V-5230D-069)

l- 7 RLMPTA029WREO Oven lamp

AK

l- 8

QSW-MAOO9WREO Monitor switch (V-5220D-070)

i AE

l- 9 RMOTEA162WREO Cooling fan motor

1

AW

l-10 RMOTDA055WREO Turntable motor

AR

l-11 RTRN-A246WREO Power transformer

:. BM

l-12

RC-QZA075WREO High voltage capacitor

AU

l-13 FH-DZA005WREO High voltage rectifier ass'y

i AP

l-14

RV-MZA089WREO Magnetron

1 BG

l-16 RTHM-A015WREO Thermal cut-out

115°C

1 AF

l-17

RR-WZA003WREO Monitor resistor 0.8n 20W

AF

1-18

FDTCTA123WRKO AH sensor assembly

t AY

CABINET PARTS

;I ;

GCABUA260WRPO Outer case cabinet

BA

GDAI-A138WRWO Base plate (Right)

i AP

-4

z- 5

LANGK0243WRPO Capacitor holder
GLEGP0021WREO Foot

2'

AC
AB

2- 6

LSTPP0065WRFO Cord anchorage (Upper)

1 AA

2- 7

LSTPP0066WRFO Cord anchorage (Lower)

AA

2- 8 LANGQ0382WRMO Earth angle

t AB

2- 9 PCUSGAlGOWREO Vibration proof cushion

1 AD

2-10

PCUSGA24OWRPO Vibration cushion

1

AD

CONTROL PANEL PARTS

3- 1 CPWBFA470WRKO Control unit (Not Replaceble Item)

1

3- 1A QCNCMA23ODREO 4-pin connector (A)

BQ

3- 1B QCNCMA275DREO 2-pin connector (B)
3- 1c

QCNCMA145DREO 3-pin connector (F)

3- 1D

QCNCWA030DREO 12-pin connector (G)

3- 1E RV-KXA009DREO Fluorescent display tube

Cl

RC-KZA087DREO Capacitor

O.lvF 50V

c2

VCEAB31VW108M Capacitor

1OOOpF 35V

c3 VCEAB31EW476M Capacitor

47pF 25V

c4

VCKYBllEX153N Capacitor

0.015pF 25V

c5

VCEAB31CW476M Capacitor

47pF 16V

C6,7,20,VCKYDllCY103N Capacitor

O.OlpF 16V

C60

C8

RC-KZA031DREO Capacitor

O.lpF 25V

c21 VCTYF31HF103Z Capacitor

O.OlpF 50V

C80

VCEAB31HW474M Capacitor

0.47pF 50V

C81 VCEAB31HW335M Capacitor

3.3pF 50V
CFl RCRS-AOlODREO Ceramic resonator CST4.00MGW
Dl-5

VHDlSR139-11B Diode (lSR139)

D60-61, VHDlSS270A/-1Diode (lSS270A)

D81-82,
D84-85,
D91-97

ICl

RH-IZA393DREO LSI

IC2

RH-IZA31ODREO IC

g:o,40

VS2SB793///-4 Transistor (2SB793)
VSDTA143ES/lB Transistor (DTA143ES)

Q30

RH-TZA063DREO Transistor (2SA933S)

AC
t AB
1

AB
1 AE

AW
t AA
1 AF

AA
i AA

AA
ii AA

1 AA
1AA

AA
t AA

AD
5' AA

13 AA

1 AV
1 AL

AC

2' AA
1 AB

32

-

R-5H53

Vote :

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

REF. NO. 1 PART NO.

I

DESCRIPTION Q’T’

-

t

i

3

Y c

:ODE

AB
AC
AC
AA
AA

Q80
Q81

z2

R2,5,85

VSDTA114YS/-3 Transistor

VSDTD143ES/-3 Transistor

RH-TZA097DREO Transistor
VRD-B12EF432J Resistor
VRD-B12EF102J Resistor

VRD-B12HF621J Resistor

VRD-B12HF751J Resistor

VRD-B12EF153J Resistor

VRD-B12EF332J Resistor

(DTA114YS)
(DTD143ES)
(DTB143ES)

4.3kn 1/4W
lkn 1/4W

62022 1/2W
75ofl 1/2w
15kfl 1/4W

3.3kn 1/4w

1

AA
AA
AA
AA

R3
R4
R6,20
R40,

R91-97

RlOO-10
R51
R60

R61

R62

VRS-B13AA331J
VRD-B12EF512J
VRD-B12EF103J
VRD-B12EFlOlJ

AA
AA
AA
AA

Resistor 33of2 1w
Resistor 5.lkn 1/4w
Resistor

lOk0 1/4W

Resistor loon 1/4w
Resistor 2OOQ 1/4w

Resistor

18D 1/4W

Resistor l.OMf-l 1/4W
Relay (OJ-SH-112LM)
Relay (VS14MB)

Buzzer (PKM22EPT-CA THAI)
Transformer

Varistor (TNR15G471K)

Zener diode (HZ6A-3)
Zener diode (HZ16-1)

i

1
1

1

i

i
1

i

i
1

1

::
1

5

-

1
1

::
1

AA
AA
AA
AH
AK

R81 VRD-B12EF201J
R82

VRD-B12EF180J

R200

VRD-B12EF105J
RYl RRLY-AO20DREC
RY2 RRLY-A059DREC

SP40 RALM-A007DREC
Tl RTRNPA067DREC
VRSl RH-VZAOlODREO
ZDl

VHEHZGA3///-1
ZD2 VHEHZlGl///-1

AF
AR
AE
AC
AA

AA
AK
AX
AD
AA

ZD3 RH-EZA105DREO Zener diode (RD4.3ESB2)

3-

2 HPNLCA901WRFO

Control panel frame

3-

3 DUNTKA491WRKO

Key unit assembly

3-

4 JBTN-A710WRFO

Open button

3-

5 MSPRDA003WREO

Open button spring

3-

6 XEPSD30PlOXSO

Screw;Control unit mounting

OVEN PARTS

AA

BN
AN
AV
AF
AA

AC
AB
AD
AD
AD

AD
AA
AM
AH
AH

AE
AA
AE
AM
AK

AB

AA
AB
AB
AD

AA

4- 1
4- 2
4- 3
4- 4
4- 5

DOVN-A171WRTO Oven cavity
FROLPA036WRKO Roller stay
NTNT-AOOlWRFO Turntable tray
PCOVP0279WREO Waveguide cover
PCLICQOOlYBEO Clip

NCPL-A015WRFO Turntable coupling
PPACGA017WREO O-ring
MHNG-A121WRMO Oven hinge (upper)
PHOK-A032WRFO Upper latch hook
PHOK-A033WRFO Lower latch hook

4- 6
4- 7
4- 8
4- 9
4-10

t

1
1
1

1

t
1
1

i

;
1

4-11
4-12
4-13
4-14
4-15

MLEVPA096WRFO Door open lever
MSPRTOlOOWREO Button spring
FDUC-A154WRYO Steam duct
PDUC-A474WRFO Fan duct
PDUC-A473WRFO Magnetron duct

FFANJ0031WRKO Fan blade assv
LSTY-0030WRE0 Fan retainer ­PCOVPA130WRPO Turntable motor cover
FDAI-AO61WRKO Base plate (left) assy
GDAI-A088WRWO Base plate (left)

GLEGP0021WREO Foot
PCUSGA154WRPO Cushion
GFTARAOOlWRWO Oven lamp access cover
PFILWA027WRPO Oven lamp filter

MHNG-A122WRMO Oven hinge (lower)

4-16
4-16A
4-17
4-18
4-18A

4-18B
4-19
4-20
4-21
4-22

I I

2

4-23

PCUSGAOGlWRPO Leader cushion

DOOR PARTS

CDORFA524WRKO Door assembly, complete.
DDORFA442WRYO Door panel
FCOVAA049WRKO Door screen assembly
GCOVHA241WRFO Choke cover
FANGKA068WRYO Latch angle

1 BP
1 BB

BB

i AH
1 AL

:- 1
5- 2
5- 3
5- 4

33

R-5H53

Note : The voltage supplied to the parts “*1 are greater than 250V.

REF. NO.

5- 5
5- 6

;I ;
5- 9

PART NO. DESCRIPTION

LSTPPA097WRFO Upper latch head
LSTPPA098WRFO Lower latch head
MLEVFA008WRPO Latch lever
MLEVPA178WRFO Head lever
MSPRT0059WREO Latch sprint

GWAKPA132WREO Door frame

$C! ;
PSHE-A022WREO Door panel sheet (L)
PSHE-A023WREO Door panel sheet (S)

S-10
5-11
5-12

*
*

6- 1
6- 2
6- 3
6- 4
6- 5

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

7- 1

2

;I 3

4

;I 5
7- 6

7- 7
7- 8
7- 9
7- 10

7- 11
7- 12
7- 13
7- 14
I- 15

7- 16
7- 17
7- 18
7- 19
7- 20

MISCELLANEOUS

QW-QZA066WREO High voltage wire A
QW-QZA067WREO High voltage wire B
TCADCA226WRRO Cook book
FW-VZA770WREO Main wire harness
TINSEA557WRRO Operation manual

TSPCNB586WRRO Name plate
TCAUHAO95WRRO Caution label
FW-VZB113WREO Stop switch harness
QTANN0033WREO cord connector

SCREW, NUT AND WASHER

LX-CZA020WREO Special screw
LX-EZA042WREO Special screw
XOTSD40P12000 Screw; M4 x 12
LX-EZA004WREO Special screw
LX-BZ0174WREO Special screw

XFPSD30P14000 Screw;

M3 x 14 zinc plated steel

XFPSD40PlOOOO Screw;

M4 x 10 zinc plated steel

XHTSD40P08RVO Screw; M4 x

8 zinc plated steel
XFPSD40PlOKOO Screw; M4 x 10 zinc plated steel
XNESD40-32000 Nut;

M4 x 3.2 zinc plated screw

XHPSD40P08KOO Screw; m4 x

8 zinc plated steel
XWWSDSO-06000 Washer;

MS x 0.6 zinc plated steel
LX-BZA036WREO Special screw
XOTSD40P12RVO Screw;

M4 x 12 zinc plated steel

XBPSD40P25000 Screw; M4 x 25 zinc plated steel
XHPSD30PlOXOO Screw;

M3 x 10 zinc plated steel

XHPSD40P22000 Screw;

M4 x 22 zinc plated steel
LX-BZA064WREO Special screw
XFPSD30PlOOOO Screw: M3 x 10 zinc plated steel
XFPSD30P08000 Screw; M8 x

8 zinc plated steel

HOW TO ORDER REPLACEMENT PARTS

4
2

z
1

1

2

;
3

41

z
1

1
5
1
2

AA
AB
AA
AA
AA

AA
AA
AA
AA
AA

AA
AA
AA
AA
AA

AA
AA
AA
AA
AA

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

1. MODEL NUMBER

2. REF. NO.

3. PART NO. 4. DESCRIPTION

(RDP1303Ll)

\

34

R-5H53

1 I 2 3 4

5 6

’ OVEN PARTS

/

1

2

3

4

/

5

6

35

R-5H53

I

B

I

I

i

,

cl

/

I

D

E

F

G

H

i

1

2

3

4

5

6

__--__

-

CABINET PARTS

1

/

2

3

-

4

5

6

36

R-5H53

1

/

2

I

3 I 4 5 6

/ CONTR

.
I

OL PANEL PARTS

C

0

3-4

,-----

-.

DOOR ASSEMBLY

/

\

/

\

/

/

/

/H

/

\ /--

/

1 /

I

2

/ 3 4

/

5 6

37

R-5H53

MISCELLANEOUS

”

P

(Capacitor)

I Capacitor) (Transformerj

l Actual wire harness may be different than illustration.

PACKING AND ACCESSORIES

l TRAY HOLDER

(SPADFA075WRE

---- .---___I_

jH.RAY PACKING FORM i 1

(SPADPAi 28WREO) ’

l Not replaceable items

‘91 0 SHARP CORP. (9k0.55E) Printed in Australia

38