OKIDATA ML390 Turbo User manual

Page: 1
Service Guide ML390/391
Chapter 0 About This Manual
ML390/ML391
Dot Matrix Printers
Adobe Acrobat printable reference
copy of the OKIDATA Service Training Manual.
09/17/97
Note: This Adobe Acrobat version of the Okidata Service Training Manual was built with the
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Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business
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Table of Contents Page
Service Guide ML390/391
0 About This Manual
Front Cover 1
Manual Copyright 2
1 Product Specifications
1.1 General Description - General Information 3
....1.1.02 Compatibility - Microline 390/391 vs. Microline
390/391-Plus 4
1.2 Product Specifications 5
1.3 Paper Specifications 6
1.4 Physical Specifications 7
1.5 Power Requirements 8
1.6 Environmental Requirements 9
1.7 Agency Approvals 10
1.8 Options 11
1.9 Consumables 12
1.10 Memory Specifications 13
1.11 Reliability Specifications 14
2 Principles of Operation
2.1 Printer Overview - General Information 15
....2.1.02 Compatibility - Microline 390/391 vs. Microline
390/391-Plus 16
2.2 Circuit Board Description 17
....Block Diagram (Microline 390/391) 18
....Block Diagram (Microline 390/391-Plus) 19
2.3 Electrical Operation - Initialization 20
....2.3.02 Interface Control 21
....2.3.03 Print Head Drive Circuit 22
....2.3.04 Spacing Operation 23
....2.3.05 Line Feed 24
....2.3.06 Alarm Circuits 25
2.4 Mechanical Principles Of Operation - Printhead 26
....2.4.02 Space Mechanism / Operation 27
........Head Gap Adjusting Mechanism 28
............Head Gap Adjusting Mechanism - Diagram 1 29
............Head Gap Adjusting Mechanism - Diagram 2 30
....2.4.03 Ribbon Drive Mechanism / Operation 31
....2.4.04 Paper Feed Mechanism 32
....2.4.05 Paper-End Detection Mechanism 33
....2.4.06 Semi-Automatic Sheet Feeder (SASF) Operation 34
....2.4.07 Release Lever Operation 35
3 Maintenance & Disassembly
3.1 Maintenance - General Information 36

Table of Contents Page
....3.1.02 Maintenance Tools 37
....3.1.03 Maintenance Precautions 38
3.2 Disassembly/Assembly Procedures 39
....3.2.01 Preliminary Items 40
....3.2.02 Separator Assembly 41
....3.2.03 Printhead Assembly 42
....3.2.04 Upper Cover Assembly 43
....3.2.05 Operator Panel Assembly 44
....3.2.06 Control Board - Revs A and B 45
........Control Board - Rev C 46
....3.2.07 IC Card (B) Panel 47
....3.2.08 Transformer - Revs A and B 48
........Transformer - Rev C 49
....3.2.09 Filter Assembly 50
....3.2.10 Power Supply Board - Revs A and B 51
........Power Supply Board - Rev C 52
....3.2.11 Power Interconnect Module / Cable Guide - Revs A
and B 53
........Power Interconnect Module / Cable Guide - Rev C 54
....3.2.12 Indicator Assembly (Bail Bar Assembly) 55
....3.2.13 Head Cable Access Cover and Connection Board
(SRBS) 56
....3.2.14 Ribbon Feed Gear Assembly 57
....3.2.15 Space Motor Assembly 58
....3.2.16 Carriage Frame Assembly 59
....3.2.17 Space Rack 60
....3.2.18 Guide Rail 61
....3.2.19 Platen Assembly 62
....3.2.20 Line Feed Motor and Gear - Line Feed Motor 63
........Line Feed Motor and Gear - Line Feed Motor Gear 64
....3.2.21 Line Feed Motor Interconnect Module 65
....3.2.22 Reset Spring, Change Gear, and Idler Gear 66
....3.2.23 Release Lever 67
....3.2.24 Paper Pressure Guide 68
....3.2.25 Pressure Roller Assembly 69
....3.2.26 Tractor Assembly 70
....3.2.27 Sensor Lever 71
....3.2.28 Paper End (B) Lever 72
....3.2.29 Main Chassis Assembly 73
3.3 Adjustments - General Information 74
....3.3.01 Printhead Gap Adjustment 75
3.4 Cleaning 76
3.5 Lubrication 77
4 Failure & Repair Analysis

Table of Contents Page
4.1 Overview - Introduction 78
....4.1.02 Compatibility - Microline 390/391 vs. Microline
390/391-Plus 79
4.2 Troubleshooting Updates 80
4.3 Reporting Problems 81
4.4 Troubleshooting Tips 82
4.5 Fault Alarms 83
4.6 Repair Analysis Procedures - Using The RAPS 84
....4.6.02 RAP Index 85
....4.6.03 Troubleshooting Cautions 86
........RAP 01: Operator Panel Lamps Do Not Light 87
........RAP 02: Abnormal Spacing 88
........RAP 03: Wrong or Missing Characters / Dots on Output 89
........RAP 04: Line Feed Problems 90
........RAP 05: Malfunction of Operator Panel Switch(es) 91
........RAP 06: Parallel Interface Does Not Receive Data 92
........RAP 07: Serial Interface Does Not Receive Data 93
4.7 Hexadecimal Dump 94
4.8 Resistance / Service Checks - Index To Charts 95
....4.8.02 Interconnect Diagrams - Microline 390/391 - Rev. A
and B 96
........Interconnect Diagrams - Microline 390/391 - Rev C 97
........Interconnect Diagrams - Microline 390/391 - Plus 98
....4.8.03 Printhead 99
....4.8.04 Space Motor 100
....4.8.05 Line Feed Motor 101
....4.8.06 Operator Panel Board 102
....4.8.07 Control Board 103
4.9 Printer Tests - General Information 104
....4.9.02 Rolling ASCII Print Test 105
....4.9.03 Font Sample Test 106
....4.9.04 Serial Interface Loopback Test 107
4.10 Menu Operation 108
4.11 Top Of Form 109
4.12 Paper Park 110
4.13 Forms Tear Off 111
A Board Diagrams
A.1 Board Reference Charts - General Information 112
....A.1.02 Compatibility - Microline 390/391 vs. Microline
390/391-Plus 113
A.2 Index To Charts - Microline 390/391: Rev A And B 114
....Index To Charts - Microline 390/391: Rev C 115
....Index To Charts - Microline 390/391 - Plus 116
....A.2.01 Control Board (SKRB) - Rev A and B 117

Table of Contents Page
....A.2.02 Control Board (SKRA) - Rev C and "Plus" Printers 118
....A.2.03 Power Supply (PAII) - Rev A and B 119
....A.2.04 Power Supply (SUII) - Rev C and "Plus" Printers 120
....A.2.05 Filter Assembly 121
....A.2.06 Operator Panel (LXSP) - Microline 390/391 122
....A.2.07 Operator Panel (LXSP-5) - Microline 390/391-Plus 123
....A.2.08 Interconnect Board (SRBS) 124
....A.2.09 RS232-C Serial Interface (LXHI) 125
B Illustrated Parts Listing
B.1 Illustrated Parts Listing - General Information 126
....B.1.02 Definitions of Terms 127
....B.1.03 Compatibility - Microline 390/391 vs. Microline
390/391-Plus 128
....B.1.04 Parts Ordering Information 129
B.2 Charts - Index 130
....B.2.01 Covers 131
....B.2.02 Electrical Components - Rev A and B 132
....B.2.03 Electrical Components - Rev C 133
....B.2.04 Printer Mechanism - Rev A and B (1 of 2) 134
....B.2.05 Printer Mechanism - Rev A and B (2 of 2) 135
....B.2.06 Printer Mechanism - Rev C (1 of 2) 136
....B.2.07 Printer Mechanism - Rev C (2 of 2) 137
....B.2.08 Operator Panel 138
....B.2.09 Carriage Assembly 139
....B.2.10 Tractor Assembly 140
....B.2.11 Options 141
....B.2.12 Consumables 142
....B.2.13 Packaging 143
....B.2.14 Documentation 144