Utax DF 791 User manual

Service
Manual
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Service
Manual
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CAUTION
RISK OF EXPLOSION IF BATTERY IS REPLACED BY AN INCORRECT TYPE. DISPOSE
OF USED BATTERIES ACCORDING TO THE INSTRUCTIONS.
It may be illegal to dispose of this battery into the municipal waste stream. Check with your
local solid waste officials for details in your area for proper disposal.
ATTENTION
IL Y A UN RISQUE D’EXPLOSION SI LA BATTERIE EST REMPLACEE PAR UN MODELE
DE TYPE INCORRECT. METTRE AU REBUT LES BATTERIES UTILISEES SELON LES
INSTRUCTIONS DONNEES.
Il peut être illégal de jeter les batteries dans des eaux d’égout municipales. Vérifiez avec les
fonctionnaires municipaux de votre région pour les détails concernant des déchets solides
et une mise au rebut appropriée.

Revision history
Revision Date Pages Revised contents

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Safety precautions
This booklet provides safety warnings and precautions for our service personnel to ensure the safety of
their customers, their machines as well as themselves during maintenance activities. Service personnel
are advised to read this booklet carefully to familiarize themselves with the warnings and precautions
described here before engaging in maintenance activities.

Safety warnings and precautions
Various symbols are used to protect our service personnel and customers from physical danger and
to prevent damage to their property. These symbols are described below:
DANGER: High risk of serious bodily injury or death may result from insufficient attention to or incorrect
compliance with warning messages using this symbol.
WARNING: Serious bodily injury or death may result from insufficient attention to or incorrect compliance
with warning messages using this symbol.
CAUTION: Bodily injury or damage to property may result from insufficient attention to or incorrect com-
pliance with warning messages using this symbol.
Symbols
The triangle ( ) symbol indicates a warning including danger and caution. The specific point of attention is
shown inside the symbol.
General warning. Warning of risk of electric shock.
Warning of high temperature.
indicates a prohibited action. The specific prohibition is shown inside the symbol.
General prohibited action. Disassembly prohibited.
indicates that action is required. The specific action required is shown inside the symbol.
General action required. Remove the power plug from the wall outlet.
Always ground the copier.

1. Installation Precautions
WARNING
• Do not use a power supply with a voltage other than that specified. Avoid multiple connections to
one outlet: they may cause fire or electric shock. When using an extension cable, always check that
it is adequate for the rated current. .....................................................................................................
• Connect the ground wire to a suitable grounding point. Not grounding the copier may cause fire or
electric shock. Connecting the earth wire to an object not approved for the purpose may cause
explosion or electric shock. Never connect the ground cable to any of the following: gas pipes, light-
ning rods, ground cables for telephone lines and water pipes or faucets not approved by the proper
authorities. ..........................................................................................................................................
CAUTION:
• Do not place the copier on an infirm or angled surface: the copier may tip over, causing injury. .........
• Do not install the copier in a humid or dusty place. This may cause fire or electric shock. .................
• Do not install the copier near a radiator, heater, other heat source or near flammable material. This
may cause fire. ...................................................................................................................................
• Allow sufficient space around the copier to allow the ventilation grills to keep the machine as cool
as possible. Insufficient ventilation may cause heat buildup and poor copying performance. ............
• Always handle the machine by the correct locations when moving it. .................................................
• Always use anti-toppling and locking devices on copiers so equipped. Failure to do this may cause
the copier to move unexpectedly or topple, leading to injury. ..............................................................
• Avoid inhaling toner or developer excessively. Protect the eyes. If toner or developer is accidentally
ingested, drink a lot of water to dilute it in the stomach and obtain medical attention immediately.
If it gets into the eyes, rinse immediately with copious amounts of water and obtain medical atten-
tion. .....................................................................................................................................................
• Advice customers that they must always follow the safety warnings and precautions in the copier’s
instruction handbook. .........................................................................................................................

2. Precautions for Maintenance
WARNING
• Always remove the power plug from the wall outlet before starting machine disassembly. ................
• Always follow the procedures for maintenance described in the service manual and other related
brochures. ..........................................................................................................................................
• Under no circumstances attempt to bypass or disable safety features including safety mechanisms
and protective circuits. ........................................................................................................................
• Always use parts having the correct specifications. ............................................................................
• Always use the thermostat or thermal fuse specified in the service manual or other related brochure
when replacing them. Using a piece of wire, for example, could lead to fire or other serious acci-
dent. ...................................................................................................................................................
• When the service manual or other serious brochure specifies a distance or gap for installation of a
part, always use the correct scale and measure carefully. ..................................................................
• Always check that the copier is correctly connected to an outlet with a ground connection. ...............
• Check that the power cable covering is free of damage. Check that the power plug is dust-free. If it
is dirty, clean it to remove the risk of fire or electric shock. .................................................................
• Never attempt to disassemble the optical unit in machines using lasers. Leaking laser light may
damage eyesight. ...............................................................................................................................
• Handle the charger sections with care. They are charged to high potentials and may cause electric
shock if handled improperly. ...............................................................................................................
CAUTION
• Wear safe clothing. If wearing loose clothing or accessories such as ties, make sure they are safely
secured so they will not be caught in rotating sections. ......................................................................
• Use utmost caution when working on a powered machine. Keep away from chains and belts. ..........
• Handle the fixing section with care to avoid burns as it can be extremely hot. ..................................
• Check that the fixing unit thermistor, heat and press rollers are clean. Dirt on them can cause
abnormally high temperatures. ...........................................................................................................

• Do not remove the ozone filter, if any, from the copier except for routine replacement. ......................
• Do not pull on the AC power cord or connector wires on high-voltage components when removing
them; always hold the plug itself. ........................................................................................................
• Do not route the power cable where it may be stood on or trapped. If necessary, protect it with a
cable cover or other appropriate item. ................................................................................................
• Treat the ends of the wire carefully when installing a new charger wire to avoid electric leaks. ..........
• Remove toner completely from electronic components. .....................................................................
• Run wire harnesses carefully so that wires will not be trapped or damaged. ......................................
• After maintenance, always check that all the parts, screws, connectors and wires that were
removed, have been refitted correctly. Special attention should be paid to any forgotten connector,
trapped wire and missing screws. .......................................................................................................
• Check that all the caution labels that should be present on the machine according to the instruction
handbook are clean and not peeling. Replace with new ones if necessary. .......................................
• Handle greases and solvents with care by following the instructions below: ......................................
· Use only a small amount of solvent at a time, being careful not to spill. Wipe spills off completely.
· Ventilate the room well while using grease or solvents.
· Allow applied solvents to evaporate completely before refitting the covers or turning the power
switch on.
· Always wash hands afterwards.
• Never dispose of toner or toner bottles in fire. Toner may cause sparks when exposed directly to
fire in a furnace, etc. ...........................................................................................................................
• Should smoke be seen coming from the copier, remove the power plug from the wall outlet immedi-
ately. ...................................................................................................................................................
3. Miscellaneous
WARNING
• Never attempt to heat the drum or expose it to any organic solvents such as alcohol, other than the
specified refiner; it may generate toxic gas. ........................................................................................
• Keep the machine away from flammable liquids, gases, and aerosols. A fire or an electric shock
might occur. ........................................................................................................................................

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3N0/3NK/3PD/3PG
CONTENTS
1-1 Specifications
1-1-1 Specifications ........................................................................................................................1-1-1
1-1-2 Parts names ..........................................................................................................................1-1-3
(1) Document Finisher ...........................................................................................................1-1-3
(2) Mail box(option) ...............................................................................................................1-1-4
(3) Bridge unit ........................................................................................................................1-1-5
1-1-3 Machine cross section...........................................................................................................1-1-6
1-2 Installation
1-2-1 Installation environment.........................................................................................................1-2-1
1-2-2 Unpacking..............................................................................................................................1-2-2
(1) Unpacking.........................................................................................................................1-2-2
(2) Removing the tapes and pads..........................................................................................1-2-5
1-3 Maintenance Mode
1-3-1 Maintenance mode................................................................................................................1-3-1
(1) Executing a maintenance item .........................................................................................1-3-1
(2) Maintenance modes item list............................................................................................1-3-2
1-4 Troubleshooting
1-4-1 Paper misfeed detection........................................................................................................1-4-1
(1) Paper misfeed indication ..................................................................................................1-4-1
(2) Paper misfeed detection component................................................................................1-4-3
1-4-2 Troubleshooting.....................................................................................................................1-4-7
(1) First check items...............................................................................................................1-4-7
(2) Items and corrective actions relating to the device that will cause paper jam................1-4-11
(3) Electrical parts that could cause paper jam at the BR (bridge) part...............................1-4-16
(4) Electrical parts that could cause paper jam at the DF paper entry,
feedshift and subtray left eject part.................................................................................1-4-17
(5) Electrical parts that could cause paper jam at the DF process part...............................1-4-19
(6) Electrical parts that could cause paper jam at the DF eject tray part.............................1-4-21
1-4-3 Self-diagnostic function .......................................................................................................1-4-22
(1) Self-diagnostic function ..................................................................................................1-4-22
(2) Self diagnostic codes......................................................................................................1-4-22
1-4-4 Electric problems.................................................................................................................1-4-44
1-4-5 Mechanical problems...........................................................................................................1-4-50
1-5 Assembly and disassembly
1-5-1 Precautions for assembly and disassembly...........................................................................1-5-1
(1) Precautions.......................................................................................................................1-5-1
1-5-2 Document finisher section .....................................................................................................1-5-2
(1) Detaching and refitting the DF main PWB........................................................................1-5-2
(1-1) Remarks on DF main PWB replacement ................................................................1-5-4
(2) Detaching and refitting the Staple unit..............................................................................1-5-5
(3) DF ejection roller, adjustment of roller intervals ...............................................................1-5-7

3N0/3NK/3PD/3PG
2-1 Mechanical Construction
2-1-1 Bridge unit section.................................................................................................................2-1-1
2-1-2 Paper insertion,feedshift and DF sub tray eject sections.......................................................2-1-2
(1) Feedshift operation to DF sub tray or prosessing section ................................................2-1-3
2-1-3 Prosessing section ................................................................................................................2-1-4
(1) Relief drum operation.......................................................................................................2-1-6
(2) Bundle discharge operation..............................................................................................2-1-7
2-1-4 Eject tray section ...................................................................................................................2-1-9
(1) Main tray elevation operation .........................................................................................2-1-11
(2) Collation..........................................................................................................................2-1-11
2-1-5 Mailbox (option)...................................................................................................................2-1-12
(1) Eject operation to mailbox tray.......................................................................................2-1-14
2-1-6 Punch unit(Option)...............................................................................................................2-1-15
2-2 Electrical Parts Layout
2-2-1 Electrical parts layout ............................................................................................................2-2-1
(1) PWBs................................................................................................................................2-2-1
(2) Switches and sensors.......................................................................................................2-2-2
(3) Motors...............................................................................................................................2-2-4
(4) Solenoids and clutch ........................................................................................................2-2-5
(5) Bridge section...................................................................................................................2-2-6
(6) Mailbox (option)................................................................................................................2-2-7
(7) Punch unit(Option)............................................................................................................2-2-8
2-3 Operation of the PWBs
2-3-1 DF main PWB........................................................................................................................2-3-1
2-3-2 Mailbox main PWB ................................................................................................................2-3-9
2-3-3 BR PWB (MFP/ PRINTER)..................................................................................................2-3-12
2-3-4 Punch unit PWB ..................................................................................................................2-3-14
2-4 Appendixes
2-4-1 Appendixes............................................................................................................................2-4-1
(1) List of maintenance parts .................................................................................................2-4-1
(2) Periodic maintenance procedures....................................................................................2-4-3
(3) Wiring diagram .................................................................................................................2-4-6
INSTALLATION GUIDE
DF-791 (3000-sheet finisher)
AK-740 (Bridge unit)
MT-730(B) (Mail box)
PH-7A/C/D (Punch unit)

3N0/3NK/3PD/3PG
1-1-1
1-1 Specifications
1-1-1 Specifications
Document Finisher
Punch unit (option)
Item Specifications
Type Floor model
Number of trays Two tray
Paper weight 45 to 256 g/m2
Tray capacity
Main Tray (Tray A)
When not stapling
A4, A4R, B5, Letter, LetterR,16K,16KR,Folio: 3000 sheets
A3, B4, B5R,Ledger, Legal, 12 × 18", 8K,
Custom (98 × 148 mm to 297 × 432 mm): 1500 sheets
A5R, B6R,Statement R: 500 sheets
Sub Tray (Tray B) A4, A4R, B5, B5R, A5R, B6R, Folio, Ledger, Legal, 12 × 18", A3, B4, 8K, Letter, Letter R, Statement-R, 16K, 16K-R, Custom (98 ×
148 mm to 297 × 432 mm):200 sheets
Stapling
Maximum Number
A3, B4, B5R, Ledger, Legal, Oficio II,
216 × 340 mm, Folio, 8K,16KR 30 sheets (52 to 90 g/m2)
20 sheets (91 to 105 g/m2)
2 cover sheet only
(106 g/m2to 256 g/m2)
A4, A4R, B5, Letter, Letter R, 16K 70 sheets (52 to 75 g/m2)
65 sheets (76 to 90 g/m2)
55 sheets (91 to 105 g/m2)
2 cover sheet only
(106 g/m2to 256 g/m2)
Media types Plain, Recycled, Prepunched, Preprinted, Bond, Letterhead, Color (Colour), Vellum, Thick, High Quality, Rough, Transparency
(OHP film), Labels, Envelope, Cardstock, Coated, Custom
Power source Electrically connected to the machine
Dimensions (W ×D ×H) 607.2 ×668.5 ×951.3 mm
23 29/32 × 26 5/16 × 37 7/16”
Weight Approx. 40 kg / Approx. 88.2 lb or less
Item Specifications
Paper size When not stapling A3, B4, A4, A4R, B5, B5R, A5R, Folio, Legal, Letter, Letter R, 12
× 18", Statement R, 12 × 18", 8K, 16K,16K-R
Paper weight 45 to 300 g/m2
Media types Plain, Transparency, Preprinted, Bond, Recycled,Rough, Letter- head, Color (Colour), Prepunched,Thick, Coated, High Quality,
Custom

3N0/3NK/3PD/3PG
1-1-2
Mail box (option)
NOTE: These specifications are subject to change without notice.
Item Specifications
Number of trays 7 trays
Paper size (80 g/m2)
A3, B4, Ledger: 50 sheets
A4, A4R, B5, B5R, A5R, Legal, Letter, Letter R, 216 × 340 mm,
Executive, Folio, Foolscap, 8K,16K, 16K-R, Statement R,
Oficio II: 100 sheets
Maximum number for storage
A3, B4, Folio, Ledger, Legal
60 to 105 g/m2: 50 sheets
106 to 163 g/m2: 25 sheets
A4, A4R, B5, B5R, A5R, Letter, LetterR, statementR, 8K, 16K,
16KR
60 to 105 g/m2: 100 sheets
106 to 163 g/m2: 50 sheets
Dimensions (W ×D ×H) 510 x 400 x 470 mm
20 1/16” x 15 3/4” x 18 1/2”
Weight Approx. 10 kg or less/22 lbs

3N0/3NK/3PD/3PG
1-1-3
1-1-2 Parts names
(1) Document Finisher
Figure 1-1-1
5
4
213
1. DF main tray(tray A)
2. DF sub tray(tray B)
3. DF top cover
4. DF front cover
5. DF operation panel

3N0/3NK/3PD/3PG
1-1-4
(2) Mail box(option)
Figure 1-1-2
1
2
1. Trays 1 - 7
2. Mailbox cover

3N0/3NK/3PD/3PG
1-1-5
(3) Bridge unit
Figure 1-1-3
1
2
3
4
5
1. BR conveying cover
2. BR cover open lever
3. BR entry guide
4. BR conveying guide
5. BR lock lever

3N0/3NK/3PD/3PG
1-1-6
1-1-3 Machine cross section
Figure 1-1-4
1 5
7
Paper path
3
2
4
6
1. DF processing section
2. Sub tray eject section
3. Main tray eject section
4. Staple unit
5. Bridge unit section
6. Mailbox (option)
7. Punch unit (option)

3N0/3NK/3PD/3PG
1-2-1
1-2 Installation
1-2-1 Installation environment
Installation location (Be based on the machine establishment place.)
Avoid direct sunlight or bright lighting. Ensure that the photoconductor will not be exposed to direct sunlight or
other strong light when removing paper jams.
Avoid locations subject to high temperature and high humidity or low temperature and low humidity; an abrupt
change in the environmental temperature; and cool or hot, direct air.
Avoid places subject to dust and vibrations.
Choose a surface capable of supporting the weight of the machine.
Place the machine on a level surface (maximum allowance inclination: 1).
Avoid air-borne substances that may adversely affect the machine or degrade the photoconductor, such as
mercury, acidic of alkaline vapors, inorganic gasses, NOx, SOx gases and chlorine-based organic solvents.
Select a well-ventilated location.