Oki Microline 520 How to use

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Microline 520/521
Service Handbook
P/N 59257803

Microline 520/521
Service Handbook

This document may not be reproduced without the written permission of the Okidata Technical Training
Group. Every effort has been made to ensure the accuracy of the information contained in this training
course. Okidata is not responsible for errors beyond its control.
©1994 by Okidata All rights reserved.
First Edition February, 1993 P/N 59257801
Second Edition September, 1993 P/N 59257802
Third Edition December, 1994 P/N 59257803
Written and produced by the Okidata Technical Training Group
Please address any comments on this publication to:
Technical Training Group
Okidata
532 Fellowship Road
Mount Laurel, NJ 08054-3499
Fax Number: [phone], ext. 7034
Okilink Login Name: Technical Training
OKIDATA is a registered trademark of Oki Electric Industry Company, Ltd.; marques deposee de Oki
Electric Industry Company, Ltd.; marca registrada, Oki Electric Industry Company, Ltd.
MICROLINE is a registered trademark of Oki Electric Industry Company, Ltd.; marque depose de Oki
Electric Industry Company, Ltd.
OkiSmart Paper Handling is a trademark of Oki Electric Industry Company, Inc.
PLUG ’n PRINT is a registered trademark of Oki America, Inc.; marque deposee de Oki America, Inc.
Bitstream is a registered trademark of Bitstream Incorporated.
Epson is a registered trademark of Seiko Epson Corporation.
IBM is a registered trademark of International Business Machine Corporation.
MS-DOS is a registered trademark of Microsoft Corporation.
PC is a registered trademark of International Business Machine Corporation.
Proprinter is a registered trademark of International Business Machine Corporation.
Windows is a trademark of Microsoft Corporation

Table of Contents
COURSE ADMINISTRATION:
OVERVIEW.................................................................................................................................i-1
RECOMMENDATIONS..............................................................................................................i-2
INFORMATION UPDATES........................................................................................................i-3
NOTICES......................................................................................................................................i-3
WHERE TO SEND TESTING MATERIALS.............................................................................i-4
MISSING ITEMS OR MISSING PAGES....................................................................................i-5
COURSE PATH ...........................................................................................................................i-6
SERVICE TRAINING..................................................................................................................i-7
SERVICE AUTHORIZATION..................................................................................................i-11
General Information........................................................................................................i-11
Answer Sheet: Microline 520/521 .................................................................................i-13
Course Critique: Microline 520/521..............................................................................i-14
Certification Test: Microline 520/521............................................................................i-16
SECTION ONE: SPECIFICATIONS
1.1 OVERVIEW....................................................................................................................1-1
1.1.01 General Information..........................................................................................1-1
1.2 PHYSICAL SPECIFICATIONS ..................................................................................... 1-2
1.2.01 Dimensions .......................................................................................................1-2
1.2.02 Printer Weight...................................................................................................1-2
1.3 POWER REQUIREMENTS............................................................................................1-3
1.3.01 Input Power.......................................................................................................1-3
1.3.02 Power Consumption..........................................................................................1-3
1.3.03 Power Frequency ..............................................................................................1-3
1.4 ENVIRONMENTAL CONDITIONS..............................................................................1-4
1.4.01 Acoustic Rating.................................................................................................1-4
1.4.01 Altitude .............................................................................................................1-4
1.4.03 Ambient Temperature and Relative Humidity (RH)........................................1-4
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1.5 AGENCY APPROVALS.................................................................................................1-5
1.5.01 Listings..............................................................................................................1-5
1.6 OPERATIONAL SPECIFICATIONS.............................................................................1-6
1.6.01 Character Matrix Sizes......................................................................................1-6
Table of Print Speed and Character Matrix ...............................................................1-6
1.6.02 Characters Per Line...........................................................................................1-6
Microline 520.............................................................................................................1-6
Microline 521.............................................................................................................1-6
1.6.03 Character Pitches ..............................................................................................1-6
1.6.04 Character Sets ...................................................................................................1-7
1.6.05 Emulations ........................................................................................................1-7
1.6.06 Fonts..................................................................................................................1-8
Near Letter Quality ....................................................................................................1-8
Utility.........................................................................................................................1-8
High Speed Draft .......................................................................................................1-8
Bar Code ....................................................................................................................1-8
1.6.07 Front Panel Switches.........................................................................................1-8
1.6.08 Graphics Resolution..........................................................................................1-8
1.6.09 Interface ............................................................................................................ 1-8
Standard .....................................................................................................................1-8
Optional......................................................................................................................1-8
1.6.10 Line Feed Increments........................................................................................1-9
Fixed ..........................................................................................................................1-9
Variable......................................................................................................................1-9
1.6.11 Line Feed Time.................................................................................................1-9
1.6.12 Menu Mode.......................................................................................................1-9
1.6.13 Paper Feed Methods........................................................................................1-10
Standard ...................................................................................................................1-10
Optional....................................................................................................................1-10
1.6.14 Paper Feed Paths.............................................................................................1-10
1.6.15 Paper Loading.................................................................................................1-10
1.6.16 Paper Out Detection........................................................................................1-10
1.6.17 Paper Tear Capabilities...................................................................................1-10
1.6.18 Print Method ...................................................................................................1-11
Printhead Type.........................................................................................................1-11
General Information...........................................................................................1-11
Overheat Protection ...........................................................................................1-11
Printhead Gap Information.......................................................................................1-12
1.6.19 Print Modes..................................................................................................... 1-14
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1.6.20 Print Speed......................................................................................................1-14
Table of Print Speed and Character Matrix .............................................................1-14
1.7 PAPER SPECIFICATIONS ..........................................................................................1-15
1.7.01 Types...............................................................................................................1-15
Card Stock................................................................................................................1-15
Continuous Form .....................................................................................................1-15
Cut Sheet..................................................................................................................1-16
Envelopes................................................................................................................. 1-16
Labels.......................................................................................................................1-17
Transparency............................................................................................................1-17
1.7.02 Length.............................................................................................................1-18
1.7.03 Number of Copies...........................................................................................1-18
1.7.04 Thickness ........................................................................................................ 1-18
1.7.05 Weight............................................................................................................. 1-19
1.7.06 Width...............................................................................................................1-19
Paper ........................................................................................................................1-19
Printing Area............................................................................................................1-19
1.8 MEMORY SPECIFICATIONS.....................................................................................1-20
1.8.01 EEPROM ........................................................................................................1-20
1.8.02 EPROM...........................................................................................................1-20
1.8.03 RAM ............................................................................................................... 1-20
1.9 CONSUMABLES.......................................................................................................... 1-21
1.9.01 Ribbon.............................................................................................................1-21
1.10 OPTIONS.......................................................................................................................1-22
1.10.01 Cut Sheet Feeders ...........................................................................................1-22
Single Bin.................................................................................................................1-22
Dual Bin...................................................................................................................1-22
1.10.02 Pull Tractor Kit ..............................................................................................1-23
1.10.04 Bottom Push Tractor Kit ................................................................................1-23
1.10.05 Serial Interface................................................................................................1-23
1.10.06 Roll Paper Stand .............................................................................................1-24
1.10.08 OKISmart Typer Utility..................................................................................1-24
1.10.09 OKISmart Panel Utility...................................................................................1-24
1.11 RELIABILITY...............................................................................................................1-25
1.11.01 Mean Time Before Failure (MTBF)...............................................................1-25
1.11.02 Mean Time To Repair (MTTR)......................................................................1-25
1.11.03 Printer Life...................................................................................................... 1-25
1.11.04 Printhead Life..................................................................................................1-25
1.11.05 Ribbon Life ....................................................................................................1-25
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1.11.06 Warranty (Limited).........................................................................................1-25
1.11.07 Service.............................................................................................................1-25
SECTION TWO: PRINCIPLES OF OPERATION
2.1 ELECTRICAL OPERATION.......................................................................................... 2-1
2.1.01 Main Control Board..........................................................................................2-2
Block Diagram...........................................................................................................2-3
Program ROM............................................................................................................2-4
RAM ..........................................................................................................................2-4
LSI..............................................................................................................................2-5
Electrically Erasable Programmable Read Only Memory (EEPROM).....................2-5
2.1.02 Initialization......................................................................................................2-6
2.1.03 Parallel Interface Control..................................................................................2-7
2.1.04 Print Control......................................................................................................2-8
LSI/Printhead Interface..............................................................................................2-8
Gap Adjust Control....................................................................................................2-9
Print Compensation Control.......................................................................................2-9
2.1.05 Space and Line Feed (SP/LF) Motor Control.................................................2-10
Line Feed Motor Control.........................................................................................2-10
Space Motor Control................................................................................................2-11
Encoder Disk............................................................................................................2-11
2.1.06 Operation Panel...............................................................................................2-12
2.1.07 Alarm Circuit ..................................................................................................2-14
Driver Circuit Alarm Processing..............................................................................2-14
Low Motor Drive Voltage Alarm ............................................................................ 2-14
Head Drive Time......................................................................................................2-15
Print Speed...............................................................................................................2-15
Head Overheat Alarm Processing............................................................................2-15
2.1.08 Power Supply Circuit......................................................................................2-16
Table of Output Voltages.........................................................................................2-16
2.2 MECHANICAL OPERATION .....................................................................................2-17
2.2.01 Printhead Mechanism......................................................................................2-17
Printhead Gap Information.......................................................................................2-18
Interconnect Diagram: Control Board to Printhead................................................2-20
Line Feed Motor Resistance .............................................................................. 2-21
Space Motor Resistance.....................................................................................2-21
Printhead Operation .................................................................................................2-22
Printhead Temperature.............................................................................................2-22
2.2.02 Spacing Mechanism........................................................................................ 2-24
Spacing Operation....................................................................................................2-24
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2.2.03 Head Gap Mechanism.....................................................................................2-26
Head Gap Setting Operation....................................................................................2-26
2.2.04 Ribbon Drive Mechanism...............................................................................2-29
Ribbon Drive Operation...........................................................................................2-29
2.2.05 Line Feed Mechanism.....................................................................................2-30
Change Lever (Paper Path Selection Lever)............................................................2-30
Paper Clamp Mechanism.........................................................................................2-30
Cut Sheet/Continuous Sheet Switching Mechanism................................................2-31
Top Feed (for cut sheet paper)...........................................................................2-31
Rear/Bottom Feed (for continuous feed paper)..................................................2-31
Cut Sheet Paper Feed Operation..............................................................................2-32
Continuous Paper Feed (Rear Tractor Mechanism).................................................2-32
Continuous Paper Feed (Pull Tractor Mechanism) .................................................2-32
Continuous Paper Feed (Bottom Tractor Feed Mechanism) ..................................2-33
Continuous Paper Feed (Push/Pull Tractor Mechanism).........................................2-33
2.2.06 Paper Detection Mechanism ..........................................................................2-34
Top Feed Paper Detection........................................................................................2-34
Rear Feed Detection.................................................................................................2-34
Bottom Feed Detection ............................................................................................2-34
2.2.07 Support Protector Mechanism.........................................................................2-35
2.2.08 Automatic Paper Load ....................................................................................2-36
Cut Sheet Paper........................................................................................................2-36
Continuous Feed Paper............................................................................................2-37
2.2.09 Paper Park ......................................................................................................2-38
Paper Park Operation...............................................................................................2-38
SECTION THREE: MAINTENANCE
3.1 OVERVIEW....................................................................................................................3-1
3.1.01 General Information..........................................................................................3-1
3.1.02 Maintenance Tools............................................................................................3-1
3.1.03 Maintenance Precautions..................................................................................3-2
3.2 DISASSEMBLY/ASSEMBLY PROCEDURES ............................................................ 3-3
General Information...................................................................................................3-3
3.2.01 Preliminary Items..............................................................................................3-4
3.2.02 Printhead Assembly..........................................................................................3-6
3.2.03 Ribbon Protector...............................................................................................3-8
3.2.04 Gear Case Assembly.......................................................................................3-10
3.2.05 Pull-up Roller Assembly.................................................................................3-12
3.2.06 Upper Cover, Access Cover, and Sheet Guide Assemblies............................3-14
3.2.07 Control Board (FJIM) .....................................................................................3-16
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3.2.08 Power Supply Assembly.................................................................................3-18
3.2.09 Operator Panel PCB (LEOP) ..........................................................................3-20
3.2.10 PC Connector..................................................................................................3-22
3.2.11 Space Motor and Roller Guide Assemblies....................................................3-24
3.2.12 Carriage Cable ................................................................................................3-26
3.2.13 Space Rack...................................................................................................... 3-28
3.2.14 Roller/Holder Backup Assembly....................................................................3-30
3.2.15 Guide Rail and Adjust Cam............................................................................3-32
3.2.16 Left Ground Plate............................................................................................3-34
3.2.17 Right Ground Plate .........................................................................................3-36
3.2.18 Rear and Cut Sheet Paper Feed Sensor Levers...............................................3-38
3.2.19 Platen Assembly..............................................................................................3-40
3.2.20 Paper Chute Assembly....................................................................................3-42
3.2.21 Line Feed Motor Assembly ............................................................................3-44
3.2.22 Reset Spring....................................................................................................3-46
3.2.23 Idle Gear and Change Lever...........................................................................3-48
3.2.24 Pressure Spring ...............................................................................................3-50
3.2.25 Carriage Shaft .................................................................................................3-52
3.2.26 Leaf Spring...................................................................................................... 3-54
3.2.27 Bottom Paper Sensor Levers........................................................................... 3-56
3.2.28 Front Pressure Roller Assembly .....................................................................3-58
3.2.29 Tractor Assembly............................................................................................3-60
3.2.30 Main Frame.....................................................................................................3-62
3.3 PRINTER ADJUSTMENTS .........................................................................................3-65
3.3.01 General Information........................................................................................3-65
3.3.02 Printhead Gap Adjustment..............................................................................3-66
General Information.................................................................................................3-66
Procedure .................................................................................................................3-68
Setup Phase........................................................................................................3-68
Printhead Gap Modification Phase ....................................................................3-68
Parallel Adjustment Phase ................................................................................. 3-68
Verification Phase..............................................................................................3-68
3.3.03 Key Combinations ..........................................................................................3-70
3.3.04 Menu Operation..............................................................................................3-71
General Information.................................................................................................3-71
Menu Mode..............................................................................................................3-71
Printing the Menu .................................................................................................... 3-72
Sample Menu........................................................................................................... 3-73
Reset Menu to Factory Defaults ..............................................................................3-75
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