Epson FX-980 - Impact Printer User manual

EPSONFX-980™
Impact Serial Dot Matrix Printer
TM-FX980
®
6(59,&(0$18$/

EPSON FX-980 Preface
i
Copyright Notice
All rights reserved. No part of this publication may be reproduced,
stored in a retrieval system, or transmitted in any form or by any means,
electronic, mechanical, photocopying, recording, or otherwise, without
the written permission of Epson America, Inc.
Epson America, Inc., assumes no liability for damages resulting from
the use of the information contained herein. While every precaution has
been taken in the preparation of this book, Epson America, Inc.
assumes no responsibility for errors and omissions.
Neither Epson America, Inc., nor its affiliates shall be liable to the
purchaser of this product or third parties for damages, losses, costs, or
expenses incurred by the purchaser or third parties as a result of:
accident, misuse, or abuse of this product or unauthorized
modifications, repairs, or alterations to this product.
Epson America, Inc. shall not be liable for any damages or problems
arising from the use of any options or any consumable products other
than those designated as Original EPSON-Approved Products by Seiko
Epson Corporation.
Trademarks
EPSON®and ESC/P®are registered trademarks of Seiko Epson.
ESC/P2™and EPSON FX-980™are trademarks of Seiko Epson
Corporation.
Epson ConnectionSM is a service mark of Epson America, Inc.
General Notice: Other product names used herein are for identification
purposes only and may be trademarks of their respective companies.
EPSON disclaims any and all rights in those marks.
Copyright © 1999 Epson America, Inc.
20770 Madronna Avenue
Torrance, CA 90509-2842

EPSON FX-980 Preface
ii
FCC Compliance Statement for American Users
This equipment has been tested and found to comply with the limits for
a Class B digital device, pursuant to Part 15 of the FCC Rules. These
limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates,
uses, and can radiate radio frequency energy and, if not installed and
used in accordance with the instructions, may cause harmful
interference to radio and television reception.
However, there is no guarantee that interference will not occur in a
particular installation. If this equipment does cause interference to radio
and television reception, which can be determined by turning the
equipment on and off, the user is encouraged to try to correct the
interface by one or more of the following measures:
 Reorient or relocate the receiving antenna.
 Increase the separation between the equipment and receiver.
 Connect the equipment into an outlet on a circuit different from that
to which the receiver is connected.
 Consult the dealer or an experienced radio/television technician
for help.
Warning
The connection of a non-shielded equipment interface cable to this
equipment will invalidate the FCC Certification of this device and may
cause interference levels that exceed the limits established by the FCC
for this equipment. It is the responsibility of the user to obtain and use a
shielded equipment interface cable with this device. If this equipment
has more than one interface connector, do not leave cables connected
to unused interfaces.
Changes or modifications not expressly approved by the manufacturer
could void the user’s authority to operate the printer.
For Canadian Users
This Class B digital apparatus meets all requirements of the Canadian
Interface-Causing Equipment Regulations.
Cet appareil numérique de la classe B respecte toutes les exigences du
Règlement sur le materiel brouilleur du Canada.

EPSON FX-980 Preface
iii
About This Manual
This manual describes basic functions, theory of electrical and mechanical operations, maintenance and repair procedures of the EPSON FX-980.
The instructions and procedures included herein are intended for experienced repair technicians. Attention should be given to the Warnings and
Cautions on the proceeding page. The chapters are organized as follows:
Contents
Chapter 1. Printer Basics
Provides feature specifications, paper handling methods,
and control panel operations.
Chapter 2. Technical Overview
Describes theory of electrical and mechanical operations.
Chapter 3. Disassembly and Assembly
Describes step-by-step procedures for disassembly and
assembly.
Chapter 4. Adjustments
Provides EPSON-approved adjustment methods.
Chapter 5. Troubleshooting
Provides troubleshooting information, including error
codes, flowcharts describing unit level troubleshooting,
sensor and motor test points, and checkpoints for the
main and power supply boards.
Chapter 6. Maintenance
Provides preventive maintenance procedures and infor-
mation about EPSON-approved lubricants required for
servicing the product.
Chapter 7. Appendix
Provides technical specifications, EEPROM address
maps, connector pin assignments, board component lay-
out diagrams, electrical circuit board schematics, and
exploded diagrams.
Symbols Used in This Manual
W ARNING Signals a precaution which, if ignored, could result in
serious injury or loss of life.
CAUTION Signals a precaution which, if ignored, could result in
damage to equipment.
CHECK
PO INT Provides helpful tips for reassembly.
ADJUSTM ENT
REQUIRED Indicates adjustments required.

EPSON FX-980 Preface
iv
General Precautions
W ARNING
 Always disconnect the product from the power
source and from peripheral devices.
 No work should be performed on the unit by
persons unfamiliar with basic safety measures
familiar to trained electronics technicians.
 When performing testing or troubleshooting
procedures in this manual, do not connect the unit
to a power source until instructed to do so. When
the power supply cable must be connected, use
extreme caution in working on the power supply
board and other electronic components.
CAUTION
 Repairs on EPSON products should be performed
only by an EPSON-certified repair technician.
 Make certain that the source voltage is the same
as the rated voltage listed on the serial number/
rating plate. If the EPSON product has a primary
AC rating different from the available power
source, do not connect it to the power source.
 Always verify that the EPSON product has been
disconnected from the power source before
removing or replacing printed circuit boards and/
or individual components.
 To protect sensitive microprocessors and
circuitry, use static discharge equipment, such as
anti-wrist straps, when accessing internal
components.
 Always replace malfunctioning components with
EPSON components. Introduction of second-
source ICs or other non-approved components
may damage the product and void any applicable
EPSON warranty.

EPSON FX-980 Contents
Contents
Printer Basics
Features ........................................................................................................ 1
Paper Handling ............................................................................................ 2
Precautions for Paper Handling ............................................................... 2
Available Paper Paths .............................................................................. 3
Control Panel Operations ........................................................................... 3
Control Panel Buttons .............................................................................. 3
Operation in Normal Mode ................................................................... 4
Operation at Power On ......................................................................... 4
LED Indicators .......................................................................................... 5
Control Panel Functions ........................................................................... 5
Micro Adjust Function ........................................................................... 5
Tear Off Function ................................................................................. 6
Self Test Function ................................................................................ 7
Hexadecimal Dump Function ............................................................... 7
Default Setting Mode ............................................................................ 7
Bidirectional Adjustment Function ........................................................ 8
EEPROM Reset Function ..................................................................... 8
Options and Consumables ......................................................................... 9
Technical Overview
Main Components ..................................................................................... 11
Housing Assembly .................................................................................... 11
Printer Mechanism .................................................................................... 12
Carriage Mechanism ................................................................................. 13
Platen Gap Adjustment Mechanisms ...................................................... 14
Paper Handling Mechanisms .................................................................... 15
Ribbon Mechanism .................................................................................... 17
Paper Methods and Feeding ..................................................................... 18
Friction .................................................................................................... 18
Push Tractor ........................................................................................... 19
Pull Tractor ............................................................................................. 20
Push and Pull Tractor in Combination .................................................... 21
C276 MAIN Board ...................................................................................... 22
Printhead Driver Circuit .......................................................................... 24
System Reset Circuit .............................................................................. 24
Carriage Motor Driver Circuit ................................................................. 25
Paper Feed (PF) Motor Driver Circuit .................................................... 27
EEPROM Control Circuit ........................................................................ 27
Sensor Circuit ......................................................................................... 28
C276 PNL Board ........................................................................................ 28
Power Supply Boards ............................................................................... 29
C166 PSB (120 V)/C166 PSE (230 V) Components .............................. 29
Operating Principles ............................................................................... 29
Circuit Operation .................................................................................... 30
Power Switch Circuit .......................................................................... 30
35 V and 5 VDC Line Over Voltage Protection Circuit ....................... 31
35 V Line Constant Voltage Control Circuit ........................................ 31
35 V Line Overload Detection Circuit ................................................. 32
35 V Line Over Current Protection Circuit .......................................... 32
5 V Line Over Current Protection Circuit ............................................ 33
5 V Line Constant Voltage Control Circuit .......................................... 33
Initialization ................................................................................................ 34
Disassembly and Assembly
Precautions ................................................................................................ 36
Tools ........................................................................................................... 36
Service Checks After Repair .................................................................... 37
Specifications for Screws ......................................................................... 38
Printer Disassembly and Assembly ........................................................ 38
Adjustments and Maintenance ............................................................... 38
Preliminary Disassembly Procedures .................................................... 40
Removing the Panel Board .................................................................... 41
Removing the Printhead ......................................................................... 42
Removing the Home Position (HP) Sensor ............................................ 43

EPSON FX-980 Contents
Removing the Paper Width (PW) Sensor ............................................... 43
Removing the Upper Housing ................................................................ 45
Removing the Platen .............................................................................. 45
Removing the Cover Open Sensor ........................................................ 46
Removing the Carriage (CR) Motor ........................................................ 47
Removing the Printer Mechanism .......................................................... 48
Removing the Paper Feed (PF) Motor ............................................... 49
Removing the Platen Gap (PG) Sensors ........................................... 50
Removing the Right Frame ................................................................ 51
Removing the Left Frame ................................................................... 54
Removing the Ribbon Drive (RD) ....................................................... 55
Removing the Carriage ...................................................................... 55
Removing the Rear Paper End (PE) Sensor ...................................... 57
Removing the Front Paper End Sensor ............................................. 58
Removing the C276 MAIN Board ........................................................... 58
Removing the C166 PSB Board ............................................................. 59
Adjustments
Required Adjustments .............................................................................. 61
Required Adjustment Tools .................................................................... 61
Using the Adjustment Program ................................................................ 62
Preparing Your Computer ...................................................................... 62
Starting the Adjustment Program ........................................................... 63
Adjusting and Resetting the Printer ........................................................ 65
Bi-D Adjustment ..................................................................................... 65
Control Panel Bi-D Adjustment ........................................................... 66
Checking Printer Data and Resetting the Printer Start Date .................. 67
Top Paper-End (TPE) Level Reset ......................................................... 68
Platen Gap Adjustment .......................................................................... 68
Troubleshooting
Using Error Codes to Isolate a Problem .................................................. 71
Print Quality Troubleshooting .................................................................. 72
Troubleshooting Other Hardware Problems ........................................... 73
Carriage Operation is Abnormal ............................................................. 73
Paper Feeding is Abnormal .................................................................... 74
Control Panel Operation is Abnormal ..................................................... 74
The Ribbon Feeds Improperly ................................................................ 75
Test Points ................................................................................................. 75
Repairing the C276 MAIN Board Assembly ............................................ 77
Repairing the C166 PSB Board Assembly .............................................. 79
Maintenance
Preventive Maintenance ........................................................................... 82
Applying Lubrication ................................................................................ 82
Appendix
Specifications ............................................................................................ 85
Mechanical ............................................................................................. 85
Environmental ........................................................................................ 86
Electrical ................................................................................................. 87
Safety Approvals .................................................................................... 88
CE Marking ............................................................................................ 88
Paper ...................................................................................................... 88
Firmware ................................................................................................ 94
Control Codes .................................................................................... 94
Character Tables ................................................................................ 94
Paper Handling Sequences ................................................................ 95
Interface ................................................................................................. 98
Parallel Interface (Forward Channel) ................................................. 98
Parallel Interface (Reverse Channel) ................................................. 99
Serial Interface ................................................................................. 101
Type-B Interface (Optional) .............................................................. 102
Interface Selection ............................................................................ 102
Cut Sheet Feeders ............................................................................... 103
C276 MAIN Board Connector Summary ................................................ 104
EEPROM Address Maps ......................................................................... 108
Component Layout Diagrams ................................................................ 115
Electric Circuit Diagrams ........................................................................ 121
Parts List for Exploded Diagrams .......................................................... 122
Exploded Diagrams ................................................................................. 129