Sharp R-1880LS User manual

1
R-1880LS/LST
Note: R-1880LST is the same as the R-1880LS, only the packing is different.
It is shipped on pallets for Recreational Vehicle distributors.
SERVICE MANUAL
In the interest of user-safety, the oven should be restored to its original condition and only parts identical to those specified should be
used.
WARNING TO SERVICE PERSONNEL: Microwave ovens contain circuitry capable of producing very high voltage and current,
contact with following parts may result in a severe, possibly fatal, electrical shock. (High Voltage Capacitor, High Voltage Power
Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..)
S66M263R1880L
OVER THE RANGE
MICROWAVE OVEN
MODEL R-1880LS/LST
TABLE OF CONTENTS
Page
PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO
AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY.......................................................................2
BEFORE SERVICING...............................................................................................................................................................2
MICROWAVE MEASUREMENT PROCEDURE ....................................................................................................................4
WARNING TO SERVICE PERSONNEL .................................................................................................................................6
FOREWORD AND WARNING ................................................................................................................................................7
PRODUCT SPECIFICATIONS .................................................................................................................................................8
GENERAL INFORMATION....................................................................................................................................................8
OPERATION............................................................................................................................................................................11
TROUBLESHOOTING GUIDE..............................................................................................................................................19
TEST PROCEDURE................................................................................................................................................................22
TOUCH CONTROL PANEL ASSEMBLY .............................................................................................................................33
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE..............................................................................40
PICTORIAL DIAGRAM .........................................................................................................................................................49
LSI UNIT CIRCUIT ................................................................................................................................................................50
PRINTED WIRING BOARD ..................................................................................................................................................51
PARTS LIST ............................................................................................................................................................................52
PACKING AND ACCESSORIES............................................................................................................................................57
This document has been published to be used for after sales service only. The contents are subject to change without notice.
SHARP ELECTRONICS CORPORATION
Service Headquarters: Sharp Plaza, Mahwah, New Jersey, 07430-2135
CONVECTION M i c r o w a v e
CONVECTION
START
MICROWAVE
Convec
Low Mix
Bake
Broil
Bake Sensor
Cook
Roast
Broil
100°F 150°F 275°F 300°F 325°F
350°F 375°F 400°F 425°F 450°F
Clock Turntable
On/Off
Custom
Help
Kitchen
Timer
Fan
Hi/Lo
Light
Hi/Lo
Stop
Clear TouchOn
Slow
Cook
High Mix
Roast
Preheat Sensor
Popcorn
Minute
Plus
Power
Level
Keep
Warm
Sensor
Reheat Defrost
1 2 3 4 5
6 7 89 0
1Cake
2Brownies
3Muffins
4Pizza
1Baked Potatoes
2FrozenVeg.
3FreshVeg. - soft
4FreshVeg. - hard
5FrozenEntrees
6Hot Dogs
7Bacon
8Fish,Seafood
1Poultry
2Chicken Pieces
3TurkeyBreast
4Pork Loin
1Hamburgers
2Chicken Breast
3Steaks
4Pork Chops
SHARP CORPORATION
SHARP ELECTRONICS OF CANADA LTD.
Head Office: 335 Britannia Road East, Mississauga, Ontario L4Z 1W9
[phone]
(IN USA):
(IN CANADA):

2
R-1880LS/LST
PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID POSSIBLE EXPO-
SURE TO EXCESSIVE MICROWAVE ENERGY
(a) Do not operate or allow the oven to be operated with the door open.
(b) Make the following safety checks on all ovens to be serviced before activating the magnetron or other microwave
source, and make repairs as necessary: (1) interlock operation (2) proper door closing, (3) seal and sealing surfaces
(arcing, wear, and other damage), (4) damage to or loosening of hinges and latches, (5) evidence of dropping or
abuse.
(c) Before turning on microwave power for any service test or inspection within the microwave generating compart-
ments, check the magnetron, wave guide or transmission line, and cavity for proper alignment, integrity, and con-
nections.
(d) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation and trans-
mission systems shall be repaired, replaced, or adjusted by procedures described in this manual before the oven is
released to the owner.
(e) A microwave leakage check to verify compliance with the Federal Performance Standard should be performed on
each oven prior to release to the owner.
BEFORE SERVICING
Before servicing an operative unit, perform a microwave emission check as per the Microwave Measurement
Procedure outlined in this service manual.
If microwave emissions level is in excess of the specified limit, contact SHARP ELECTRONICS CORPORA-
TION immediately @1-800-237-4277.
If the unit operates with the door open, service person should 1) tell the user not to operate the oven and 2)
contact SHARP ELECTRONICS CORPORATION and Food and Drug Administration's Center for Devices
and Radiological Health immediately.
Service personnel should inform SHARP ELECTRONICS CORPORATION of any certified unit found with
emissions in excess of 4mW/cm2. The owner of the unit should be instructed not to use the unit until the oven
has been brought into compliance.

3
R-1880LS/LST
NOTES:

4
R-1880LS/LST
MICROWAVE MEASUREMENT PROCEDURE (USA)
A. Requirements:
1) Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave oven should
not exceed 1mW/cm2at any point 5cm or more from the external surface of the oven, measured prior to acquisition by a purchaser,
and thereafter (through the useful life of the oven), 5 mW/cm2at any point 5cm or more from the external surface of the oven.
2) Safety interlock switches Primary interlock relay and door sensing switch shall prevent microwave radiation emission in excess of
the requirement as above mentioned, secondary interlock switch shall prevent microwave radiation emission in excess of 5 mW/cm2
at any point 5cm or more from the external surface of the oven.
B. Preparation for testing:
Before beginning the actual measurement of leakage, proceed as follows:
1) Make sure that the actual instrument is operating normally as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for instrumentation as prescribed by the performance standard for micro-
wave ovens, 21 CFR 1030.10(c)(3)(i), must be used for testing.
2) Place the oven tray in the oven cavity.
3) Place the load of 275±15 ml (9.8 oz) of tap water initially at 20±5½C (68½F) in the center of the oven cavity.
The water container shall be a low form of 600 ml (20 oz) beaker with an inside diameter of approx. 8.5 cm (3-1/2 in.) and
made of an electrically nonconductive material such as glass or plastic.
The placing of this standard load in the oven is important not only to protect the oven, but also to insure that any leakage is
measured accurately.
4) Set the cooking control on Full Power Cooking Mode
5) Close the door and select a cook cycle of several minutes. If the water begins to boil before the survey is completed, replace it
with 275 ml of cool water.
C. Leakage test:
Closed-door leakage test (microwave measurement)
1) Grasp the probe of the survey instrument and hold it perpendicular to the gap between the door and the body of the oven.
2) Move the probe slowly, not faster than 1 in./sec. (2.5 cm/sec.) along the gap, watching for the maximum indication on the meter.
3) Check for leakage at the door screen, sheet metal seams and other accessible positions where the continuity of the metal has been
breached (eg., around the switches, indicator, and vents).
While testing for leakage around the door pull the door away from the front of the oven as far as is permitted by the closed latch
assembly.
4) Measure carefully at the point of highest leakage and make sure that the highest leakage is no greater than 4mW/cm2, and that the
secondary interlock switch does turn the oven OFF before any door movement.
NOTE: After servicing, record data on service invoice and microwave leakage report.

5
R-1880LS/LST
MICROWAVE MEASUREMENT PROCEDURE (CANADA)
After adjustment of the door switches are completed individually or collectively, switch test and microwave leakage test must be per-
formed with survey instrument and test result must be confirmed to meet the requirement of the performance standard
for microwave ovens as undermentioned.
A. Requirements:
Every microwave oven shall function in such a manner that when the oven is fully assembled and operating with it's service
controls and user controls adjusted to yield the maximum output, the leakage radiation, at all points at least 5 cm. from the
external surface of the oven, does not exceed:
1) 1.0mW/cm2 with the test load of 275 ± 15 ml of water at an initial temperature 20 ±5oC.
2) 5.0mW/cm2 when the outer enclosure is removed with a test load of 275 ± 15 ml of water at an initial temperature 20±5oC.
3) 5.0mW/cm2 without a test load.
B. Preparation for testing:
Before beginning the actual measurement of leakage, proceed as follows:
1) Make sure that the actual instrument is operating normally as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for instrumentation as prescribed by CSA and NHW performance standard for
microwave ovens must be used for testing recommended instruments are , NARDA 8100 and NARDA 8200.
2) Place the oven tray in the oven cavity.
3) Place the load of 275±15 ml of tap water initially at 20±5oC in the center of the oven cavity.
The water container shall be a low form of 600 ml beaker with an inside diameter of approx. 8.5 cm (3-1/2 in.) and made of an
electrically nonconductive material such as glass or plastic.
The placing of this standard load in the oven is important not only to protect the oven, but also to insure that any leakage is measured
accurately.
4) Set the cooking control on Full Power Cooking Mode, Close the door and select a cook cycle of several minutes. If the water begins
to boil before the survey is completed, replace it with 275 ml of cool water.
C. Leakage test with enclosure installed :
1) Grasp the probe of the survey instrument and hold it perpendicular to the gap between the door and the body of the oven.
2) Move the probe slowly, not faster than 2.5 cm/sec. along the gap, watching for the maximum indication on the meter.
3) Check for leakage at the door screen, sheet metal seams and other accessible positions where the continuity of the metal has been
breached (eg., around the switches, indicator, and vents).
While testing for leakage around the door pull the door away from the front of the oven as far as is permitted by the closed latch
assembly.
4) Measure carefully at the point of highest leakage and make sure that the highest leakage is no greater than 4mW/cm2, and that the
secondary interlock switch does turn the oven OFF before any door movement.
C. Leakage test without enclosure:
1) Remove the enclosure (cabinet).
2) Grasp the probe of the survey instrument and hold it perpendicular to all mechanical and electric parts of the oven that is accessible
to the user of the oven including, but not limited to, the waveguide, cavity seams, magnetron gap between the door and the body
of the oven.
3) Move the probe slowly, not faster than 2.5 cm/sec. along the gap, watching for the maximum indication on the meter.
4) Measure carefully at the point of highest leakage and make sure that the highest leakage is under 5mW/cm2.
CAUTION: Special attention should be given to avoid electrical shock because HIGH VOLTAGE is generated during this test
No Load test
1) Operate the oven without a load and measure the leakage by the same method as the above test procedure " Leakage test with
enclosure installed"
2. Make sure that the highest leakage should not exceed 5mW/cm2.
NOTE: After servicing, record data on service invoice and microwave leakage report.

6
R-1880LS/LST
WARNING TO SERVICE PERSONNEL
Microwave ovens contain circuitry capable of producing
very high voltage and current, contact with following
parts
may result in a severe, possibly fatal, electrical
shock.
(Example)
High Voltage Capacitor, High Voltage Power Trans-
former, Magnetron, High Voltage Rectifier Assembly,
High Voltage Harness etc..
Read the Service Manual carefully and follow all in-
structions.
Before Servicing
1. Disconnect the power supply cord , and then
remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
WARNING:RISK OF ELECTRIC SHOCK.
DISCHARGE THE HIGH-VOLTAGE
CAPACITOR BEFORE SERVICING.
The high-voltage capacitor remains charged about 60 seconds
after the oven has been switched off. Wait for 60 seconds and
then short-circuit the connection of the high-voltage capacitor
(that is the connecting lead of the high-voltage rectifier) against
the chassis with the use of an insulated screwdriver.
Whenever troubleshooting is performed the power supply must
be disconnected. It may in, some cases, be necessary to connect
the power supply after the outer case has been removed, in this
event,
1. Disconnect the power supply cord, and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the leads to the primary of the power
transformer.
5. Ensure that these leads remain isolated from other components
and oven chassis by using insulation tape.
6. After that procedure, reconnect the power supply cord.
When the testing is completed,
1. Disconnect the power supply cord, and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Reconnect the leads to the primary of the power
transformer.
5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is
installed.
7. Run the oven and check all functions.
After repairing
1. Reconnect all leads removed from components during
testing.
2. Reinstall the outer case (cabinet).
3. Reconnect the power supply cord after the outer case is
installed.
4. Run the oven and check all functions.
Microwave ovens should not be run empty. To test for the pres-
ence of microwave energy within a cavity, place a cup of cold
water on the oven turntable, close the door and set the power to
HIGH and set the microwave timer for two (2) minutes. When
the two minutes has elapsed (timer at zero) carefully check that
the water is now hot. If the water remains cold carry out Before
Servicing procedure and re-examine the connections to the
component being tested.
Whenall serviceworkis completedandtheovenis fullyassembled,
the microwave power output should be checked and microwave
leakage test should be carried out.
Don't Touch !
Danger High Voltage

7
R-1880LS/LST
PRODUCT DESCRIPTION
GENERAL INFORMATION
OPERATION
TROUBLESHOOTING GUIDE AND
TEST PROCEDURE
TOUCH CONTROL PANEL
COMPONENT REPLACEMENT
AND ADJUSTMENT PROCEDURE
WIRING DIAGRAM
PARTS LIST
SERVICE MANUAL
MICROWAVE OVEN
R-1880LS/LST
FOREWORD
This Manual has been prepared to provide Sharp Electronics Corp. Service
Personnel with Operation and Service Information for the SHARP MICRO-
WAVE OVENS, R-1880LS/LST.
It is recommended that service personnel carefully study the entire text of this
manual and the base model's manual so that they will be qualified to render
satisfactory customer service.
Check the interlock switches and the door seal carefully. Special attention
should be given to avoid electrical shock and microwave radiation hazard.
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 no other visible damage with the oven.
Servicing and repair work must be carried out only by trained service person-
nel.
DANGER
Certain initial parts are intentionally not grounded and present
a risk of electrical shock only during servicing.Service person-
nel - Do not contact the following parts while the appliance
is energized;
High Voltage Capacitor, Power Transformer, Magnetron, High
Voltage Rectifier Assembly, High Voltage Harness;
If provided, Vent Hood, Fan assembly, Cooling Fan Motor.
All the parts marked “*” on parts list are used at voltages more than
250V.
Removal of the outer wrap gives access to voltage above 250V.
SHARP ELECTRONICS CORPORATION
SHARP PLAZA, MAHWAH,
NEW JERSEY 07430-2135

8
R-1880LS/LST
ITEM DESCRIPTION
Power Requirements 120 Volts / 13.2 Amperes (Microwave), 13.2 Amperes (Convection) - [UL Rating]
116 Volts / 13.2 Amperes (Microwave), 13.2 Amperes (Convection) - [CSA Rating]
60 Hertz
Single phase, 3 wire grounded
Power Output 850 watts (IEC-705 TEST PROCEDURE)
Operating frequency of 2450MHz
Convection Power Output 1400 watts
Case Dimensions Width 29-15/16"
Height 16-11/32"
Depth 15- 9/32"
Cooking Cavity Dimensions Width 17-1/8"
Height 8-1/16"
1.1 Cubic Feet Depth 13-13/16"
Hood lamp 2 bulbs, 20W x 2, Incandescent light bulbs
Hood fan Horizontal discharge 230 C.F.M. , Vertical discharge 240 C.F.M. ,
Control Complement Touch Control System
Clock ( 1:00 - 12:59 )
Timer (0 - 99 min. 99 seconds)
Microwave Power for Variable Cooking
Repetition Rate;
P-HI ............................................................. Full power throughout the cooking time
P-90................................................................................. approx. 90% of Full Power
P-80................................................................................. approx. 80% of Full Power
P-70................................................................................. approx. 70% of Full Power
P-60................................................................................. approx. 60% of Full Power
P-50................................................................................. approx. 50% of Full Power
P-40.................................................................................. approx. 40% of Full Power
P-30 ................................................................................. approx. 30% of Full Power
P-20................................................................................. approx. 20% of Full Power
P-10....................................................................................approx. 10% of Full Powe
P-0..................................................................No power throughout the cooking time
Custom Help pad, Sensor Cook pad, Broil pad, Roast pad
Bake pad, Sensor Reheat pad, Minute plus pad, Sensor Popcorn pad
Defrost pad, Convect pad, Preheat pad, Low mix Bake pad
High mix Roast pad, Broil pad, Slow Cook pad, Kitchen Timer pad
Number and temperature selection pads, Clock pad, Keep Warm pad
Turntable On / Off pad, Power Level pad, Stop/Clear pad,
Start / Touch On pad, Fan Hi/Lo, Light Hi/Lo.
Oven Cavity Light Yes 20W x 1 Incandescent light bulb
Safety Standard UL Listed FCC Authorized
DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J
Canadian Standards Association.
Health CANADA, Industry CANADA.
Weight Approx. 71 lbs.
SPECIFICATION
GENERAL INFORMATION
GROUNDING INSTRUCTIONS
This oven is equipped with a three prong grounding plug. It must be plugged into a wall receptacle that is properly installed and
grounded in accordance with the National Electrical Code and local codes and ordinances.
In the event of an electrical short circuit, grounding reduces the risk of electric shock by providing an escape wire for the electric
current.
WARNING: Improper use of the grounding plug can result in a risk of electric shock.

9
R-1880LS/LST
Electrical Requirements
The oven is equipped with a 3-prong grounding plug. DO NOT UNDER ANY CIRCUMSTANCES CUT OR REMOVE THE
GROUNDING PIN FROM THE PLUG.
The power supply cord and plug must be connected to a separate 120 Volt AC, 60 Hz, 15 Amp. or more branch circuit, using a grounded
receptacle. The receptacle should be located inside the cabinet directly above the Microwave Oven/Hood system mounting location.
1. Oven door with see-through window.
2. Door hinges.
3. Sirrer cover.
4. Turntable motor shaft.
5. Oven lamp.
It will light when oven is operating or door is open.
6. Door latches.
The oven will not operate unless the door is securely closed.
7. One touch door open button.
Push to open door.
8. Auto-Touch control panel.
9. Time display: Digital display, 99 minutes 99 seconds.
10. Ventilation openings.
11. Light Cover.
12. Grease filters.
13. Removable turntable.
The turntable will rotate clockwise or counterclockwise.
Only remove for cleaning.
14. Removable turntable support.
15. Plug
3-Pronged Plug Grounded
Receptacle Box
Grounding Pin
3-Pronged Receptacle
OVEN DIAGRAM
66
1
12
11
10
15
9
8
13
14
7
2
35
4

10
R-1880LS/LST
NOTE:
Some one-touch cooking features as "More Time " are disabled after one minute when the oven is not used.
These features are automatically enabled when the door is opened and closed or the STOP/ CLEAR pad s
are pressed.
CONTROL PANEL
CONVECTION
START
MICROWAVE
Convec
Low Mix
Bake
Broil
Bake Sensor
Cook
Roast
Broil
100°F 150°F 275°F 300°F 325°F
350°F 375°F 400°F 425°F 450°F
Clock Turntable
On/Off
Custom
Help
Kitchen
Timer
Fan
Hi/Lo
Light
Hi/Lo
Stop
Clear Touch On
Slow
Cook
High Mix
Roast
Preheat Sensor
Popcorn
Minute
Plus
Power
Level
Keep
Warm
Sensor
Reheat Defrost
1 2 3 4 5
6 7 89 0
1 Cake
2 Brownies
3 Muffins
4 Pizza
1 Baked Potatoes
2 Frozen Veg.
3 Fresh Veg.- soft
4 Fresh Veg.- hard
5 Frozen Entrees
6 Hot Dogs
7 Bacon
8 Fish,Seafood
1 Poultry
2 Chicken Pieces
3 Turkey Breast
4 Pork Loin
1 Hamburgers
2 Chicken Breast
3 Steaks
4 Pork Chops