Epson 850 Service Manual

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EPSON Stylus Color 850

®

4009157

NOTICE



All rights reserved. No part of this manual 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 prior written permission of SEIKO EPSON CORPORATION.



The contents of this manual are subject to change without notice.



All effort have been made to ensure the accuracy of the contents of this manual. However,
should any errors be detected, SEIKO EPSON would greatly appreciate being informed of
them.



The above not withstanding SEIKO EPSON CORPORATION can assume no responsibility for
any errors in this manual or the consequences thereof.

EPSON is a registered trademark of SEIKO EPSON CORPORATION.
General Notice: Other product names used herein are for identification purpose only and may

be trademarks or registered trademarks of their respective owners. EPSON
disclaims any and all rights in those marks.

Copyright © 1996 SEIKO EPSON CORPORATION. Printed in Japan.

PRECAUTIONS

Precautionary notations throughout the text are categorized relative to 1)Personal injury and 2)
damage to equipment.

DANGER

WARNING

The precautionary measures itemized below should always be observed when performing
repair/maintenance procedures.

Signals a precaution which, if ignored, could result in serious or fatal personal
injury. Great caution should be exercised in performing procedures preceded by
DANGER Headings.

Signals a precaution which, if ignored, could result in damage to equipment.

DANGER

1. ALWAYS DISCO NNECT T HE PRODUCT FROM THE POWER SOURCE AND PERIPHERAL
DEVICES PERFORMING ANY MAINTENANCE OR REPAIR PROCEDURES.

2. NOWORK SHOULD BE PERFORMED ON THE UNIT BY PERSONS UNFAMILIER WITH
BASIC SAFETY MEASURES AS DICTATED FOR ALL ELECTRONICS TECHNICIANS IN
THEIR LINE OF WORK.

3. WHEN PERFORMING TESTING AS DICTATED WITHIN 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 POWER SUPPLY AND OTHER ELECTRONIC COMPONENTS.

WARNING

1. REPAIRS ON EPSON PRODUCT SHOULD BE PERFORMED ONLY BY AN EPSON
CERTIFIED REPAIR TECHNICIAN.

2. MAKE CERTAIN THAT THE SOURCE VOLTAGES IS THE SAME AS THE RATED
VOLTAGE, LIST ED ON THE SERIAL NUMBER/RAT ING PLATE. IF T HE EPSON PRODUCT
HAS A PRIMARY AC RATING DIFFERENT FROM AVAILABLE PO W ER SOURCE, DO NOT
CONNECT IT TO THE POWER SOURCE.

3. ALWAYS VERIFY THAT T HE EPSON PRODUCT HAS BEEN DISCONNECT ED FROM THE
POWER SOURCE BEFORE REMOVING OR REPLACING PRINTED CIRCUIT BOARDS
AND/OR INDIVIDUAL CHIPS.

4. IN ORDER TO PROTECT SENSITIVE MICROPROCESSORS AND CIRCUITRY, USE
STATIC DISCHARGE EQUIPMENT, SUCH AS ANTI-STATIC WRIST STRAPS, WHEN
ACCESSING INTERNAL COMPONENTS.

5. REPLACE MALFUNCTIONING COMPONENTS ONLY WITH THOSE COMPONENTS BY
THE MANUFACTURE; INTRODUCTION OF SECOND-SOURCE ICs OR OTHER
NONAPPROVED COMPONENTS MAY DAMAGE THE PRODUCT AND VOID ANY
APPLICABLE EPSON WARRANTY.

PREFACE

This manual describes basic functions, theory of electrical and mechanical operations,
maintenance and repair procedures of St ylus Color 850. The inst ruct ions and procedures included
herein are intended for the experienced repair t echnicians, and attention should be given to the
precautions on the preceding page. The chapters are organized as follows:

CHAPTER 1. PRODUCT DESCRIPTIONS

Provides a general overview and specifications of the product.

CHAPTER 2. OPERATING PRINCIPLES

Describes the theory of electrical and mechanical operations of the product.

CHAPTER 3. TROUBLESHOOTING

Provides the step-by-step procedures for troubleshooting.

CHAPTER 4. DISASSEMBLY AND ASSEMBLY

Describes the step-by-step procedures for disassembling and assembling the product.

CHAPTER 5. ADJUSTMENTS

Provides Epson-approved methods for adjustment.

CHAPTER 6. MAINTENANCE

Provides preventive maintenance procedures and the lists of Epson-approved lubricants and
adhesives
required for servicing the product.

APPENDIX

Provides the following additional information for reference:

• Connector pin assignments

• Electric circuit boards components layout

• Exploded diagram

• Electrical circuit boards schematics

REVISION STATUS

Rev. Date Page(s) Contents

A 1998/04/9 All First release

TABLE OF CONTENTS

PRODUCT DESCRIPTIONS

1.1 FEATURES ..........................................................................................1-1

1.1.1 Options..........................................................................................................1-2

1.2 HARDWARE SPECIFICATIONS..........................................................1-3

1.2.1 Printing Specifications ................................................................................1-3

1.2.2 Print Speed and Printable Columns ...........................................................1-4

1.3 MAIN COMPONENTS..........................................................................1-5

OPERATING PRINCIPLES

2.1 OVERVIEW..........................................................................................2-1

DISASSEMBLY AND ASSEMBLY

ADJUSTMENT

4.1 OVERVIEW..........................................................................................4-1

TROUBLESHOOTING

MAINTENANCE

APPENDIX

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PRODUCT DESCRIPTIONS



EPSON Stylus Color 850

Chapter 1 Product Descriptions

1.1 FEATURES

The EPSON Stylus COLOR 800/850 are a high-performance color ink jet printer designed for the
small office/home office (SOHO) market. The main features of this printer are:



High print quality for color graphics



High resolution 1440 (H) x 720 (V) dpi printing

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Colors Cyan, Magenta, Yellow, Black



Printing method Traditional and new Microweave printing



Smaller dot diameter Stylus Color 800 uses Normal and Micro dot.

Stylus Color 850 uses Normal, Micro, Super micro dot.



High-speed printing



400 cps in LQ mode



533 cps in Draft mode



Built-in auto sheet feeder with a wide page capability and high capacity
This printer holds: 100 cut-sheets (55 g/m

10 envelopes
20 sheets of glossy paper
30 index cards
50 transparency film sheets
70 sheets of special paper

2

)



Two interfaces built-in and one optional Type-B interface card slot



Mac serial interface (up to approximately 900Kbps)



Bi-directional parallel interface (IEEE-1284 level 1 device)



Optional Type-B interface card slot



High speed paper loading and ejecting.
Printing speed is same as Stylus Color 800, but paper eject speed is improved for Stylus Color

850.



4 scalable fonts and 5 LQ fonts

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Scalable fonts Roman T, Sans Serif H, Roman, Sans Serif



LQ fonts Roman, Sans Serif, Courier, Prestige, Script



9 usable character tables (NLSP version)
Italic, PC437, PC850, PC437 Greek, PC852, PC853, PC855, PC857, PC866, PC869,
MAZOWIA, Code MJK, ISO 8559-7, Latin ISO Latin 1T, Bulgaria, PC774, Estonia, ISO 8859-2,
PC866 LAT, PC866 UKR, PCAPTEC, PC708, PC720, PCAR864, PC860, PC865, PC861,
Hebrew7*1, Hebrew8*2, PC862(Hebrew)*1.

CAUTION

Character with “*1” in the character table above is the hidden character
table which is not mentioned in the user’s guide and is also not able to
set on the default setting.

Rev. A

1-1

2

1.1.1 Options

Part Number Description

C82305/C82306
C82307/C82308

C82310∗
C82313∗
C82315∗
C82314∗
C82312∗
C82331∗
C82345∗

C836021∗

C83603∗/C83604∗

C83605∗
C83606∗
S020108
S020089
S041059
S041025
S041060
S041061
S041026
S041062
S041067
S041054
S041121
S041122
S041071
S041072
S041107
S041126
S041124
S041063
S041064
S041106

EPSON Stylus Color 850

Chapter 1 Product Descriptions

Table 1-1. Options

Serial interface card
32KB serial interface
32KB parallel interface card
32KB EEE-488 interface card
TWAIN interface card
Coax interface card
LocalTalk™ interface card
Ethernet interface card
Type B bi-directional parallel interface card
Parallel interface cable (shielded)

(D-SUB 25-pin to Amphenol 57)
Serial interface cable
(D-SUB 25-pin to D-SUB 25-pin)
Serial interface cable
(D-SUB 9-pin to D-SUB 25-pin)

Black ink cartridge
Color ink cartridge
EPSON 360 dpi ink jet paper (A4) / 100 sheets pack
EPSON 360 dpi ink jet paper (A4) / 200 sheets pack
EPSON 360 dpi ink jet paper (Letter) / 100 sheets pack
EPSON photo-quality Ink jet paper (A4) / 100 sheets pack
EPSON photo-quality Ink jet paper (A4) / 200 sheets pack
EPSON photo-quality ink jet paper (Letter) / 100 sheets pack
EPSON photo-quality ink jet paper (Legal) / 100 sheets pack
EPSON photo-quality ink jet card (A6) / 50 sheets pack
EPSON photo-quality ink jet card (5.8 inches)
EPSON photo-quality ink jet card (10.8 inches)
EPSON photo-quality glossy film (A4) / 15 sheets pack
EPSON photo-quality glossy film (Letter) / 15 sheets pack
EPSON photo-quality glossy film (A6) / 10 sheets pack
EPSON photo-quality glossy paper (A4)
EPSON photo-quality glossy paper (Letter)
EPSON ink jet transparencies (A4) / 30 sheets pack
EPSON ink jet transparencies (Letter) / 30 sheets pack
EPSON photo-quality self-adhesive sheets (A4) / 10 sheets pack

Note) Asterisk in a part number replaces the last digit of the part number, which varies by
country.

Rev. A

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EPSON Stylus Color 850

3

Chapter 1 Product Descriptions

1.2 HARDWARE SPECIFICATIONS

1.2.1 Printing Specifications



Print method: On-demand ink jet



Nozzle configuration: Monochrome (Black) 128 nozzles (32 x 4 staggered)

Color (magenta, cyan, yellow) 64 nozzles (32 X 2 staggered,

each color)

320/360 inch

32/360 inch

#128

144/360 inch

#127

32/360 inch

#125#126

32/360 inch

144/360 inch

32/360 inch

#64

#63

144/360 inch

32/360 inch

#64

#63

#64

#63

#2 #3#4#1

Black Cyan

Paper feed direction

Figure 1-1. Nozzle Configuration



Print direction Bi-directional with logic-seeking

CAUTION

Heads of Stylus Color800 and Stylus Color850 has compatibility each
other. However, since the head of Stylus Color850 is able to discharge
for super micro dot, the parts code number and price are different from
the head of Stylus Color800. Therefore, when you need to order head,
order each head exclusively made for that model. As the head of Stylus
Color 850, the lot number which is written on the side (opposite side to
the side head ID is written), is ended with “J”.

#1

#2

Magenta

#1

#2

Yellow

#1

#2

Rev. A

1-

EPSON Stylus Color 850

4

Chapter 1 Product Descriptions

1.2.2 Print Speed and Printable Columns

Table 1-2. Print Speed and Printable Columns in Character Mode

Character Pitch Printable Columns LQ Speed Draft Speed

10 cpi (Pica) 80 400 cps 533 cps
12 cpi (Elite) 96 480 cps 640 cps
15 cpi 120 600 cps 800 cps
17 cpi (Pica condensed) 137 684 cps 912 cps
20 cpi (Elite condensed) 160 800 cps 1067 cps

Table 1-3. Print Speed and Printable Area for Raster Graphics Mode

Print Mode Printable Area Available Dots CR Speed

180 dpi x 180 dpi 8.27 inch 1488 26.7 ips
360 dpi x 360 dpi 8.27 inch 2976 20 ips
720 dpi x 720 dpi 8.27 inch 5952 20 ips
1440 dpi x 720 dpi *

1

8.27 inch 5952 *

2

10 ips

Note)
*1: Printing at 1440 x 720 dpi is available only using the driver microweave.
*2: Can be printed by sending following command sequence:

1) Print 360 x 180 raster image.

2) Paper feed 15/720 inch.

3) Move 1/1440 inch print position.

4) Print 360 x 180 raster image.

5) Paper feed 15/720 inch.

6) Move 2/1440 inch print position.

7) Print 360 x 180 raster image.

8) Paper feed 15/720 inch.

9) Move 3/1440 inch print position.

10) Print 360 x 180 raster image.

11) Paper feed 15/720 inch.

12) Repeat 1) to 11).

Rev. A

1-

EPSON Stylus Color 850

5

g

Chapter 1 Product Descriptions

1.3 MAIN COMPONENTS

The main components of the Stylus COLOR 800/850 are:

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Main control board C202 MAIN board

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Power supply board C202 PSB/PSE board



Control panel bard C202 PNL board



Printer mechanism



Housing

The following figure shows the main component layout of the Stylus COLOR 850.

Housin

CAUTION

C202 PNL Board Assembly

C202 MAIN Board Assembly

C202 PSB/PS E Board Assemb ly

Printer Mechanism

Figure 1-2. Stylus COLOR 800/850 Main Components

Main control boards for Stylus Color800 and Stylus Color850 are same
C202 main control board. However, the version of the board for Stylus
Color850 is different and code number is also different from the one of
Stylus Color800. The content of ROM and Gate Array are changed.

Rev. A

1-

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OPERATING PRINCIPLES



EPSON Stylus Color 850

Chapter2 Operating Principles

2.1 OVERVIEW

Compared with printing mechanism parts and electric circuit parts of Stylus Color800, following
differences can be found in Stylus Color 850.



Printing Mechanism: By registering same 5 digits head ID as Stylus Color800 to

EEPROM, using exclusive program, ID for super micro dot can be
calculated and registered automatically.



Electric Circuit: C202PSB/E power supply boards of Stylus Color850 has

compatibility with boards of Stylus Color800. Also, although board
name “C202 Main control board” are same for both Stylus Color 800
and 850, code numbers are different for each model because of
following reasons.

1) Program ROM:
Each mechanism sequence is changed and can deal with
higher speed through put than Stylus Color800.

2) Gate Array(IC2):
Program for controlling head, which is registered in the Gate
Array, is changed and various data to generate trapezoidal
waveform for super micro dot is already registered.

Except for differences mentioned above, the basic components about printer mechanism and
electric circuit are same as ones of Stylus Color 800, refer to Service Manual of Stylus Color 800
for more details.

Rev. A

2-1

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

DISASSEMBLY AND ASSEMBLY

Since basic component of Stylus Clor850 is same as the one of Stylus Color800, refer to Service
Manual of Stylus Color 800 for disassembly and assembly procedure.

ADJUSTMENT

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

EPSON Stylus Color 850

Chapter4 Adjustment

4.1 OVERVIEW

Note following points, although adjustment item is same as Stylus Color 800.



Since the program is not Basic but made by “C” Language and designed for the purpose of
repairing, it differs from the one on the manufacture line. Symptom of fatal error does not
occur, even if adjustment item is freely selected. Also, even if the waste ink sequence is
activated, important data such as various adjustment values or RIP Module are not cleared.



Unlike Stylus Color 800, there is no selection on the screen for setting the destination, and only
confirmation of the model name appears on the initial menu.



There is no Uni-D adjustment in Stylus Color 800, it is necessary to perform this for Stylus
Color 850. There is no rule that which adjustment (Bi-d adjustment or Uni-D adjustment)should
be done first. However, like the previous models, following adjustments should be done for the
mechanism around the head;(Refer to Table4-1 on the Service Manual of Stylus Color800 for
more details)

1) Initial Ink Charge→2)Head ID Input→3)Head Angular Adjustment→4)Head
Linear(height) adjustment→5)Head Gap Adjustment, then perform Bi-D adjustment or Uni­D adjustment.



Since the adjustment for Stylus Color850 supports Bi-d Communication, there are following
benefits.



Current Head ID value can be checked on the PC screen.



Current protection counter value can be checked on the PC screen.



Current adjustment values of Bi-D, Uni-D and Head Gap Adjustment can be checked on the
PC screen.



Although the pattern, which is mixed with black and magenta is printed and checked for the
head gap adjustment in many of the previous models, please note that magenta portion is
mixture of magenta and cyan in the Stylus Color 850. There are some cases that the speed of
fired ink differs because of difference of color material even when the same amount of energy
is put through PZT. Therefore, color head itself can be checked by this pattern.
If you find a head that magenta and cyan are not mixed and each color can be distinguished
respectively, exchange the color head. Also, the head gap adjustment that a user can perform
through utility in the built-in function and printer driver, the pattern is printed out by black and
magenta, as it is same as in the previous models.



The printer can print printing patterns 3 times in A4 size sheet for the Head Angular
Adjustment(Bk or CMY). After third printing is completed, the printer ejects the paper
automatically. If you can not complete the adjustment in one sheet, select “Head Angular
Adjustment” again and feed another paper sheet.



2 A4 size sheets are necessary for A4 check pattern.

Rev. A

4-1

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

TROUBLESHOOTING

Since the basic component of Stylus Color850 is same as the one of Stylus Color800, refer to
Trouble shooting in Service Manual of Stylus Color 800 for actual procedure.

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

MAINTENANCE

Since the basic component of Stylus Color850 is same as the one of Stylus Color800, refer to
“Maintenance” in Service Manual of Stylus Color800.

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

APPENDIX

Since the basic component of Stylus Color850 is same as the one of Stylus Color800, refer to
“Appendix” in Service Manual of Stylus Color800.