Fritz Gegauf Bernina artista 630 User manual

Service-Manual_artista_630_640_english_V4.01_032069_50_04.doc 1
Service Manual
artista 630-640
Version 4
© Fritz Gegauf Ltd.
BERNINA sewing machines
8266 Steckborn
Switzerland

Service-Manual_artista_630_640_english_V4.01_032069_50_04.doc 2
Chapter 1
General information
1.1 Safety Regulations
Caution!
All electrical and electronic components operate at dangerous voltages. Remove the mains plug
before making any adjustments to the machine. Wait about 30 seconds after removing the plug
(capacitor discharge).
This service manual is intended to help with minor repairs and adjustments.
The instructions do not claim to be complete or comprehensive. The manual does not provide guidance
for complete assembly or disassembly.
Important:
To enable the work described to be performed correctly, the sewing and embroidery computer
must be in good mechanical and electrical condition (running smoothly, properly oiled and all
leads connected)! When adjustments are carried out in the correct order, the sewing/embroidery
computer will function without a problem.
It is important that only devices approved and distributed by BERNINA® are connected to the
sewing/embroidery computer ports.
When servicing or repairing, always use genuine parts and original accessories, either those
delivered with the machine or purchased afterwards.
These are the following:
•Mains cable
•Foot control unit
•Buttonhole foot
•Presser foot 1
•Bobbin case with bobbin
•Other accessories
•BERNINA stitch length regulator (BSR) foot (if applicable).
The Service Manual and Instructions are protected by copyright laws. These documents are
delivered exclusively to the recipient. It is forbidden to copy, distribute, forward, publish or to
reproduce them in any form without the express prior consent of Fritz Gegauf AG, BERNINA
Steckborn, Switzerland. It is also forbidden to record this Service Manual and Instructions on any
retrieval system, or to translate it, or parts of it, into any human or computer-related language of
any kind, whether electronically, mechanically, magnetically, or otherwise. Furthermore, it is
prohibited to disclose the Service Manual and Instructions to third parties without the express
written approval of Fritz Gegauf AG, BERNINA Sewing machine manufacturers, Steckborn,
Switzerland.
This Manual is subject to revisions without notice. The recipient is responsible for updating the
information provided by Fritz Gegauf AG, BERNINA Sewing machine manufacturers, Steckborn,
Switzerland.
Masthead
Author: Hans Peter Horn
Layout/typesetting: Hans Peter Horn
Print:

Service-Manual_artista_630_640_english_V4.01_032069_50_04.doc 3
1.2 Warning: Dangerous voltage levels!
Caution!
The L-Print power circuitry, the S-Print CFL voltage supply and the mains cable all carry dangerous
voltages.
For your own safety do not touch the L-Print and S-Print until about 30 seconds after the main voltage has
been switched off. This is the time required for the capacitors to discharge.
Warning!
The sewing/embroidery computer may only be connected to the mains supply when the chassis covers
are mounted. Work on the L-Print, S-Print and mains cable may only be carried out when the mains plug
has been removed from the mains supply.
Caution! High voltage!
Caution! High voltage!

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1.3 Contents
Chapter 1 General information.........................2
1.1 Safety Regulations.....................................2
1.2 Warning: Dangerous voltage levels!..........3
1.3 Contents.....................................................4
1.4 Note on Electrostatic Discharge (ESD)......6
1.5 Tools and gauges.......................................7
Chapter 2 Description of technical details
and electronics ...................................................9
2.1 BERNINA artista 630/640 technical
specifications....................................................9
2.2 Cleaning...................................................10
2.3 Block diagram ..........................................11
2.4 PCBs, plugs and cables...........................12
2.5 General functions of the PCBs.................16
Chapter 3 Functional check and diagnostic
instructions.......................................................18
3.1 Functional check ......................................18
3.2 Diagnostic instructions.............................18
3.3 Sewing-off (a-640 must be sewn-off with
the head cover fitted (light will affect the
threader sensor).............................................19
3.4 External cleaning......................................19
Chapter 4 Replacing Assemblies....................20
4.1 Removing covers .....................................20
4.2 Thread pre-tensioner................................21
4.3 Vertical spool pin......................................22
4.4 Horizontal spool pin and rear thread-guide
eyelet..............................................................22
4.5 Carrying handle........................................23
4.6 Magnifying-glass holder and thread cutter24
4.7 S-Print, keypads, front panel, RET-Print,
touch screen, display and side cover (plugs).25
4.8 P-Print ......................................................27
4.9 L-Print.......................................................28
4.10 CFL.........................................................29
4.11 Presser foot lifter sensor (micro switch).29
4.12 Buttonhole sensor PCB..........................31
4.13 Main motor (complete unit only).............31
4.14 Stitch width stepping motor....................32
4.15 Stepping motor, stitch length and
crankshaft.......................................................33
4.16 Presser foot pressure sensor.................34
4.16 Presser foot pressure sensor.................35
4.17 Winder motor..........................................35
4.18 Base shaft ..............................................36
4.19 artista 630 hook race ring.......................38
4.20 artista 640 stitch plate holder.................39
4.21 Rotary hook (RH), cutting blade and hook
drive belt in artista 640...................................40
4.22 Drive belt (synchronization of main and
base shaft)......................................................41
4.23 artista 630 upper thread tension............41
4.24 artista 640 upper thread tension............42
4.25 Thread take-up lever, thread take-up lever
crank, needle bar and link piece ....................43
Chapter 5 Adjustments...................................44
5.1 Tensioning the drive belt..........................44
5.2 Tensioning the base shaft belt.................44
5.3 artista 640 hook drive belt tension...........45
5.4 Bobbin winder..........................................45
5.5 Position of the head frame plate..............46
5.6 Presser foot fixation.................................46
5.7 Presser foot height...................................47
5.8 Darning foot height ..................................47
5.9 Straight stitch needle position (needle
distribution) ....................................................48
5.10 Stitch width limiter..................................48
5.11 Thread guide plate plate adjustment on
artista 630......................................................49
5.12 Position of driver in hook race of
artista 630......................................................49
5.13 Thread passage on artista 630..............49
5.14 Bobbin case retainer position on
artista 640......................................................50
5.15 artista 630 CB hook, synchronization,
feed and needle drive....................................51
5.16 artista 640 RH hook, synchronization,
feed and needle drive....................................53
5.17 Needle/hook distance............................54
5.17 Needle/hook distance............................55
5.18 artista 630 needle height .......................56
5.19 artista 640 needle height .......................56
5.20 Threader ................................................57
5.21 Feed-dog position in stitch plate............57
5.22 Feed-dog height.....................................58
5.23 Position of synchronizing disc (rough-
adjustment)....................................................59
5.24 Basic balance setting.............................59
5.25 Basic presser foot lifter setting
(Free Hand System (FHS))............................61
5.26 Thread tension release..........................62
5.27 Basting and long stitch device
artista 640......................................................62
5.27 Basting and long stitch device
artista 640......................................................63
5.28 artista 630 CB hook lower thread tension
(basic setting).................................................64
artista 640 RH hook lower thread tension
(basic setting).................................................64
5.29 artista 630 upper thread tension (basic
setting)...........................................................65
5.30 artista 640 upper thread tension (basic
setting)...........................................................65
5.31 Thread regulator spring .........................66
Chapter 6 Service Program............................67
6.1 Starting the test program.........................67
6.2 Virtual keyboard.......................................69
6.3 Menu 1 – Service information..................70
1a Sewing/embroidery computer basic data:
...................................................................70

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1b Sewing/embroidery computer soft- and
firmware data:............................................71
1c Sewing/embroidery computer operating
time data....................................................71
1d Sewing/embroidery computer stitch
counter data:..............................................72
1e BSR (BERNINA Stitch Regulator) data:72
1f Sewing/Embroidery computer servicing
data:...........................................................72
1g Saving of customer data.......................73
1h Customer data: .....................................73
1i Dealer data:............................................73
1j Log file....................................................74
6.4 Menu 2 – screen and beeper..................74
2a Touch screen calibration:......................74
2b LCD (screen):........................................75
2c Blank black LCD (screen):....................75
2d Blank white LCD (screen):....................75
2e Speaker test:.........................................76
6.5 Menu 3 – Signals and sensors.................76
3a Stitch width and stitch length adjusting
knobs functions..........................................76
3b Functioning of keyboard: ......................76
3c Start/stop unit (SSU) slide control:........77
3d & 3d1 Foot control: ...............................77
3f Presser foot pressure sensor:................78
3g Presser foot lifter micro switch:.............78
3h Winder motor micro switch: ..................78
3i Feed-dog drop light barrier: ...................79
3j artista 640 lower thread indicator:..........79
3k Upper thread indicator: .........................79
3l BERNINA Stitch Regulator (BSR) foot: .80
3m Buttonhole signals A & B.....................80
3n Positioning PCB (P-Print): ....................81
3n Mechanical fine-adjusting of P-Print:....81
3q USB host interface:...............................82
3s EMB interface:.......................................82
3t Foot control interface:............................82
3u BSR foot interface:................................83
6.6 Menu 4 – Motor functions.........................83
4a Stitch length stepping motor:................83
4b Stitch width stepping motor:..................84
4c artista 640 upper thread tension stepping
motor:.........................................................84
4d All stepping motors:..............................84
4f Stitches per minute (SPM) calibration:..85
4g Standard SPM (stitches per minute)
speed:........................................................86
4h Calibrating the SSU (Start/stop unit):...86
4i Standard SSU speed:............................86
4j Automatic start/stop:..............................87
4k Winder motor:.......................................87
4l Basting magnet: artista 640...................87
4m Thread cutter clamping magnet:
artista 640..................................................88
4n Thread cutting process: artista 640......88
6.7 Menu 5 – Adjustments.............................89
5a Sewing-off (customer’s view): ..............89
5b Electronic balance calibration:..............90
5b Mechanical balance fine-adjusting:......90
5b Mechanical balance fine-adjusting:......91
5b Electronic balance fine-adjusting:.........91
5c Buttonhole calibration:..........................92
5e Presser foot pressure sensor calibration
(end stops):................................................92
5f Electronic upper thread tension:
artista 640..................................................93
5g BERNINA Stitch Regulator (BSR) foot
sewing program:........................................93
5h BSR foot update:..................................94
5i Resetting artista 640 upper thread tension
to default....................................................94
5j Resetting to factory settings (Reset All):94
6.8 Menu 6 – Embroidery module (EMB)......95
6a Embroidery module basic data:............95
6b Free-arm adapter sensor:.....................96
6c X-axis sensor:.......................................97
6d Y-axis sensor:.......................................97
6e X- and Y-movement of stepping
motors:.......................................................98
6f Movement of stepping motor X: ............98
6g Movement of stepping motor Y: ...........98
6h Hoop reference position: ......................99
6i Embroidering using the test design:......99
6j Customer’s embroidery view:..............101
Chapter 7 Updating.......................................101
7.1 Updating of sewing/embroidery
computer......................................................101
7.2 BSR update............................................102
5h BSR foot update:................................102
7.3 Update – alternative access ..................103
8. Chapter Lubrication Plan .........................104
8.1 Lubrication Plan artista 630...................104
8.2 Lubrication Plan artista 640 supplementary
to artista 630................................................105

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1.4 Note on Electrostatic Discharge (ESD)
Protection of electrical and electronic components against electrostatic
discharges
Be sure to follow these important guidelines:
1. Always work at a stationary, ESD-compliant workstation equipped with the appropriate protective
devices including conductive table and floor mat, earth connection box and earthing wristband when doing
service work.
The cable of the earthing wristband must have a built-in resistance of 1 M ohm to ensure protection.
2. Always put on an earthing wristband before starting to work. Always remove any synthetic parts like
plastic bags, covers etc. from your workstation.
3. Only open ESD protective packaging at your ESD-proof workstation while wearing an earthing
wristband. Electronic components must be placed on conductive table mats only. Packing is carried out
under the same conditions.
4. Only use conductive plastic/foil pouches and ESD transport boxes for dispatching electronic
components – even if the components might be faulty.
5. Treat faulty PCBs the same as good ones to prevent addition harm.
Electrostatic charges are caused by:
•a person's walking (influence) over synthetic tilled or carpeted floor
•friction between and separation of two insulating materials (triboelectricity)
If this static electricity discharges through electronic components, these may be
partially or irreparably damaged. Electrostatically charged persons represent the
greatest danger for components. This can be dissipated by controlled electrostatic
discharge.

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1.5 Tools and gauges
Required tools and gauges (commercially available, not available from BERNINA): Multimeter, IC-
Extraction tool and TORX screw driver sizes: No. 6, 8, 9, 10, 12, 15, 20, and 25.
1 2 3 4
5 6
7
8
9
10 11
12 13 14 15
16 17
18
19 20
21
24
23
22
25 26
27

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No. Part number Description No. Part number Description
1 398 083 030 Circlip mounting tool 15 031 563.50.00 Eccentric key head frame
2 398 112 030 Spring mounting tool 16 007 993.50.00 Angular key Torx 8
3 398 097 030 Rectifying tool bobbin case
spring 17 030 883.50.00 Distance gauge for auto threader
4 001 361.70.00 Eccentric key 18 Commercially
available Digital Multimeter
5 001 357.70.00 Rectifying tool driver/hook
play 19 Commercially available IC-Extraction tool (EEPROM)
6 006 038.50.00 Spring balance gauge 20 031 939.70.00 Bobbin winder gauge
7 001 358.70.00 Lower thread tension CB 21 398 031 133 Presser foot height
8 006 543.70.01 Lower thread tension RH 22 398 024 030 Feed-dog height
9 398 080 040 Upper thread tension 22 398 022 030 Feeler gauge 0,3 mm
10 006 765.71.00 Hook race gauge CB 23 398 111 030 Feeler gauge 0,15 mm
11 032 051.70.00 Centering gauge 640
Parallel setting gauge (Set) 24 030 652.50.00 Pinning tool for Stepp motor SL
12 030 349.70.00 Pinning tool short (Set) 25 023 054.50.01 Service cable 50mm 10 pol.
12 030 430.51.00 Pinning tool 26 031 134.50.01 Service cable 50mm 30 pol.
13 001 356.50.00 Angular pinning tool 27 Commercially
available Composite Tweezers (disconnecting cables)
14 007 937.50.00 Pinning tool base shaft 031 950.70.00 BERNINA USB Stick 64MB
1.6 Where and how to use the service cables # 25 and 26
Where to use:
•In order to have the artista 630 and 640 machines under power whilst the covers have been taken
off, it is necessary to use the service cables 023 054.50.01 (50mm 10 pole) and 031 134.50.01
(50mm 30 pole).
How to use:
1. Observe ESD regulations (page 6).
2. Remove the power cord
3. Remove the covers (pages XXXX). The removed covers must be placed on the ESD mat.
4. Attach the service cables very carefully (straight) to the S-Print and P-Print. The artista 630 only
needs the 30 pole cable. The artista 640 needs also the 10 pole cable.
5. Attach an external CFL sewing light to the S-Print.
Note: Without the CFL sewing attached, the screen will not have any background lighting!
6. Fit the connection cable L-Print / S-Print.
7. Place both the back and front covers together and using the snapper clips, clip together.
8. When necessary the motor cable can also be connected.
9. Connect the power cable and switch the machine on. In order to get into the service program one
has to press the reverse button whilst switching on the machine.
Attention: Make sure that no cable is pinched, trapped or otherwise damaged.

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Chapter 2
Description of technical details and electronics
2.1 BERNINA artista 630/640 technical specifications
Features artista 630 artista 640
Max. stitch length forward in mm...................5..............................................5
Increment in mm............................................0,15.........................................0,15
Max. stitch length reverse in mm...................5..............................................5
Stitch width in mm .........................................5,5...........................................9,0
Increment in mm............................................0,23.........................................0,23
Data interface................................................USB.........................................USB
Hook system..................................................BERNINA CB..........................BERNINA RH
Needle system...............................................130/705 H ..............................130/705 H
Adjusting needle............................................130/705H TCN 80...................130/705H TCN 80
Sideways motion ...........................................no............................................no
Feed-dog drop...............................................yes ..........................................yes
Feed-dog drop via FHS.................................yes ..........................................yes
Needle positions............................................11............................................11
Stitch programs:
Total number of buttonhole types..................7..............................................8
Buttonhole length measuring system............yes ..........................................yes
Quilting stitches.............................................25............................................28
Total number of utility stitches.......................26............................................26
Total number of decorative stitches ..............145..........................................189
Alphabets ......................................................4..............................................5
Eyelets...........................................................2..............................................2
Total number of stitch patterns......................250..........................................300
Functions:
Automatic basic settings................................yes ..........................................yes
Display of recommended optimum settings ..yes ..........................................yes
Display of selected stitch...............................on display................................on display
Clear (clr) button............................................yes ..........................................yes
Balance..........................................................electronically...........................electronically
Sideways mirroring........................................yes ..........................................yes
Permanent reverse sewing............................yes ..........................................yes
Memory (mem) ..............................................yes ..........................................yes
Pattern end....................................................yes ..........................................yes
Securing at pattern beginning/ending............yes ..........................................yes
Upper thread indicator...................................yes ..........................................yes
Lower thread indicator...................................no............................................yes
BSR – BERNINA stitch length regulator........yes ..........................................yes
Integrated threader........................................yes ..........................................yes
Hopper mechanism .......................................yes ..........................................yes
Longstitch setting...........................................no............................................yes
Adjustable presser-foot pressure ..................yes ..........................................yes
Free Hand System (FHS) presser foot lifter..yes ..........................................yes
Automatic upper thread tension ....................no............................................yes
Automatic lower thread cutter........................no............................................yes
Operating controls
Screen ...........................................................graphic LCD............................graphic LCD
Colors ............................................................256..........................................256
Size in mm (inch)...........................................80x60 (3.2x2.4).......................80x60 (3.2x2.4)
Number of pixels............................................320x240..................................320x240

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Features artista 630 artista 640
Screen backlighting.......................................yes/white.................................yes/white
Direct stitch/function selection.......................yes/touch screen.....................yes/touch screen
Stitch width bar display..................................yes ..........................................yes
Stitch length bar display ................................yes ..........................................yes
Integrated service program............................yes ..........................................yes
Drive/power unit
Universal power PCB (L-Print), 100-240 Voltyes ..........................................yes
Power max.....................................................100 W......................................100 W
Motor..............................................................DC/65W30V............................DC/65W30V
Sewing speed................................................100-900 S.p.M ........................100-900 S.p.M
Embroidery stitching speed ∅.......................600 S.p.M................................600 S.p.M
Needle stop ...................................................yes ..........................................yes
Needle stop via foot control...........................yes ..........................................yes
Main power switch.........................................yes ..........................................yes
Mechanical data / housing
Diametral capacity in mm .............................190x110 /215..........................190x110 / 215
(inch)..............................................................(7.5x4.3 / 10.2)........................(7.5x4.3 / 10.2)
Overall length in mm (inch)............................385 (15)...................................385 (15)
Overall width in mm (inch).............................175 (7).....................................175 (7)
Overall height in mm (inch)............................308 (12)...................................308 (12)
Sewing light ..................................................CFL.........................................CFL
Presser foot level in mm................................7,5...........................................7,5
Weight in kg (without accessories) (lbs)........approx. 9.7 (approx. 21) .........approx. 9.7 (approx. 21)
2.2 Cleaning
Remove covers and clean.
Electrostatic charging may occur during cleaning. To prevent this, use antistatic office-equipment cleaning
agents.
We use and recommend BASF’s SURFACE CLEAN surface cleaner
It forms a protective film against static electricity, and is suitable for both plastic and metallic surfaces.
Inside parts
Dust, lint, thread and fabric remnants can accumulate inside the machine behind the covers and may lead
to malfunctions.
In the head frame area, this frequently occurs in particular in the thread take-up (joints), the main shaft
(behind the balance piece) and the thread tension device.
In the base area it occurs in:
the bobbin case,
the feed-dog,
the hook,
the hook drive,
the hook race,
the base shaft (lift and advance eccentric),
and in the toothed rack.
The main and base shaft belts and their tension units can also be affected by the accumulation of dust,
lint, thread and fabric remnants, as well as by belt residue.
Attention!
Never use alcohol,
petrol, spirits or any
corrosive fluids, or
abrasive pastes!

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2.3 Block diagram
The electronics of the BERNINA artista 630/640 are primarily accommodated in three main modules
(PCBs) – the L-Print (power PCB), the P-Print (positioning PCB) and the S-Print (control via micro-
processor).
Proce
ssor
L-Print
Winder
Motor DC
Presser Foot
Pressure Winder Motor
Motor SB
Motor SL
Motor SP
S-Print
S-Print
S-Print
Mains Switch
Mains Plug
L-Print
Main Motor Drive
USB Host
EMB
Foot Control
EMB Module
Foot Control Unit
Sensor Feed-Dog Drop
Lower Thread Sensor
Main Motor
30 V / DC
LCD / Background-
Lighting
Touch Screen
RET-
Upper Thread
Sensor
CFL Background
Light Converter
S
D
R
A
M
Flash
FPGA
Buttonhole
Sensor
Presser Foot
Sensor
Clamping
Magnet Sensor
BSR
Sewing Light
S-Print
S-Print
RET-
Print
P-Print
P-Print P-Print
Threader
Sensor
USB Client
Stepping
Motor Drivers
USB Stick
PC
Stitch width
Stitch length
Upper thread tension

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2.4 PCBs, plugs and cables
artista 640 positioning PCB
Note:
Never connect or disconnect the connecting cables when the machine is powered!
4 Pole yellow = Upper thread
tension motor
2 Pole black = Presser-foot
position micro switch
4 Pole white = Stitch width
stepping motor
4 Pole Red = BSR sensor
4 Pole white = Buttonhole
sensor
3 Pole red = Presser foot
pressure control
2 Pole white = Clam
p
ma
g
net
4 Pole
y
ellow = Winder motor
5 Pole white = Threader
PCB and basting magnet
30 Pole white = S-Print
4 Pole blue = Stitch
length stepping motor
10 Pole white = S-Print

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artista 630 positioning PCB
Note:
Never connect or disconnect the connecting cables when the machine is powered!
4 Pole blue = Stitch
length stepping motor
30 Pole white = S-Print
2 Pole black = Presser-foot
position micro switch
4 Pole white = Stitch width
stepping motor
4 Pole Red = BSR sensor
4 Pole white = Buttonhole
sensor 3 Pole red = Presser foot
pressure control
4 Pole
y
ellow = Winder motor

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P-Print (artista 630 & 640) reverse side
Note:
Never connect or disconnect the connecting cables when the machine is powered!
Sensors
Upper thread
sensor
L-Print
L-Print 8 pole
white
S-Print 7
p
ole
Ret-Print

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Ribbon cable function
What to Test What to adjust Desired status
Electrical resistance of cable Disconnect mains plug, remove
covers and unplug cables from
both printed circuits
Visual check Check cables for damage, short
circuits, and line disconnections
Check plug and socket for
damage, bent or loose contacts
Electronic measurement by
ohmmeter or continuity tester
(beeper)
Set measuring instrument to
beeper or Ohm area.
Check each cable wire.
This involves placing the
measuring tips on the top of the
connector against the metal
cutters to check each wire
against the other.
Each wire individually:
If the wire is OK:
•Ohm on the ohmmeter:
beep signal on beeper.
Defective wire:
Ohm on Ohmmeter: no beep
signal on beeper (interruption).
Each wire against the other
wires:
If the wire is OK:
Ohm on Ohmmeter: no beep
signal on beeper
Defective wire:
•Ohm on ohmmeter; beep
signal on beeper (short
circuit, squashed wires)
Caution!
High voltage !
S-Print

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2.5 General functions of the PCBs
The microcomputer on the S-Print receives an analogue signal from the foot control which is converted
into a digital signal and reported as a nominal value. The motor r.p.m is adjusted to the required value by
comparison of the predetermined and actual values. When the foot control is released (nominal value
zero) the microcomputer switches on the electrical brake. The motor is stopped very quickly in the
required needle position.
On switching on the sewing/embroidery computer, the stepping motors may be in any given position. The
microcomputer control memory may also have any given value. The stepping motors are moved to their
pinning position by means of a command from the microcomputer to give a defined situation. This position
is then registered and set to zero in the memory. This zero position then allows any stitch program to be
selected and sewn.
The S-Print controls the processes between the individual stepping motors, evaluates the signals of the
sensor and shows the results on the display.
RET-Print (return)
P-Print
The P-Print accommodates
the synchronizing disc light
barriers, and the motor and
sensor connections.
The RET-Print
accommodates three
buttons and the upper
thread indicator light
barrier.

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Universal L-Print (power)
The power PCB (L-Print) is installed in the cover at
the back of the sewing machine.
The circuit components of the L-Print producethe
following direct current voltages:
5 V/DC for the logics on the S-Print
12 V/DC for the sewing light
30 V/DC for the main motor, winder
motor and stepping motors
16 V/DC for the motor control on the
S-Print
In the event of malfunction, the F2 (T-3, 15A
secondary) /F3 (F-4A primary) fuses protect
components against overload. If a fuse blows, this is
always for a reason. The cause must be identified
and removed. An original replacement fuse of the
correct rating must be used. It is essential to test the
functions on replacing the fuse.
The L-Print and S-Print are connected via an 8-pin
ribbon cable.
Fuse F 2 T- 3,15 A Item no. 031 999.50.00
Fuse F 3 F- 4 A Item no. 031 999.50.01
S-Print
The S-Print is manufactured according to S.M.D. (Surface Mounted Device)
technology.
S.M.D. components facilitate very compact circuitry.
S.M.D. printed circuits cannot be repaired with conventional tools!
The sewing computer data is saved on an
EEPROM on the S-Print.
If the S-Print needs to be replaced, that EEPROM
must be moved to the new S-Print.
EEPROM markings must match.
F2
F3
EEPROM

Service-Manual_artista_630_640_english_V4.01_032069_50_04.doc 18
Chapter 3
Functional check and diagnostic instructions
3.1 Functional check
A correct functional check must be carried out in order to make an error diagnosis.
1) Visual check:
Spool holder
Thread guiding parts
Needle in general, and needle position
Stitch plate
Feed-dog
Bobbin case
Hook, thread guide plate, bobbin case Retainer
Hook driver
2) Functional check:
Functioning of FHS presser foot lifter
Functioning of feed-dog drop
Functioning of presser foot pressure setting
Removal of bobbin case
Functioning of automatic (artista 640) and
manual thread cutter
Connecting machine with original cable and foot
control
LCD screen with backlighting
Functioning of sewing light
Functioning of left and right needle position
Functioning of stitch length and stitch width
Functioning of CLR button
Functioning of winder motor
Test-run the machine and listen for unusual
noises and noise level
Inspect main-, foot-control- and ribbon cables for
loose contacts and electrical resistance.
Drive check of stepping motors.
Inspect USB, embroidery module, PC and foot
control interfaces for connection capabilities.
Note machine’s operating hours, firmware
version and balance values in service program.
3) Mechanical checks:
Remove all covers.
Cleaning of mechanical parts
Check bevel gears for wear and tear
Checking of:
Main shaft play
Base shaft play
Thread take-up lever
Needle bar support
Feed-dog
Functioning of bobbin case hinge
Functioning of upper and lower thread tension.
Lubricate the machine.
4) Sewing checks:
Sewing-off using the following:
Functioning of the Quick reverse button
(securing stitches)
Straight stitch
Zigzag stitch
Honeycomb stitch
Automatic buttonhole stitch
Automatic darning
Embroidery module (if there is one) using the
test embroidery design
BSR foot (if available)
3.2 Diagnostic instructions
Powering the stepping motors
¾In order to allow the stepping motors to operate correctly, it is essential that they are returned to
their "zero" position after each restart of the sewing computer or change of function. In order to
adjust this "zero" position, the stepping motors must be powered (under current). Replacement
motors should be adjusted before they are fitted into the machine. To achieve this, the motor must
be connected to the P-Print at the appropriate plug, which in turn must be connected to the S-
Print, and the S-Print to the power supply. Plug in the power cable, then select pinning positions in
the service program (SP 4e). This program powers the stepping motors to their correct current
values. The motors can then be adjusted according to the servicing instructions of the service
manual.

Service-Manual_artista_630_640_english_V4.01_032069_50_04.doc 19
Saving the data before carrying out any servicing or repair work
¾Customer and machine data must be recorded on a BERNINA USB data stick before starting
servicing or repair work. This is to avoid loss of data when replacing PCBs or updating the
firmware, and for use when comparing with the factory settings. The machine data is saved on a
replaceable EEPROM (Electrically Erasable Programmable Read-Only Memory) on the S-Print.
This EEPROM can only be exchanged with a special tool and in an ESD environmental workplace
(see page 6).
3.3 Sewing-off (a-640 must be sewn-off with the head cover fitted (light
will affect the threader sensor)
¾Sewing-off is a way of checking whether the adjustments made have had the desired effect, and
that the machine is functioning correctly.
¾The following stitches should be checked in sequence using the appropriate criteria.
1)
Straight stitch
Is the thread regulator spring
being moved correctly?
Is the row of stitching straight?
Is the thread feed regular?
2)
Zigzag (default values)
Is the stitch formation
symmetrical?
Is the thread feed regular?
Is the fabric free from puckering?
3)
Satin stitch
Is the stitch formation
symmetrical?
Is the thread feed regular?
Is the fabric free from puckering?
4)
Running stitch
Is the stitch formation
symmetrical?
Is the thread feed regular on both
sides?
Is the fabric free from puckering?
5)
Balance using “9” & “Leaf”
pattern
Is the stitch formation
symmetrical?
The stitched outline in the '9' and
the leaf must correctly meet up.
6)
Any other stitch (e. g.
Honeycomb stitch)
Is the stitch formation
symmetrical?
Is the thread feed regular?
Is the fabric free from puckering?
7)
Buttonhole
Standard buttonhole:
Is the stitch formation
symmetrical?
Are the beads of equal length?
Is the feed correct?
Automatic buttonhole:
Is the stitch formation
symmetrical?
Are the beads of equal length?
Is the feed correct?
Keyhole buttonhole:
Is the stitch formation
symmetrical?
Are the beads of equal length?
Is the feed correct?
Is the stitch formation of the
eyelet part symmetrical?
8)
Sew-off samples for the
customer
At the end of the service, a
sample is prepared for the
customer so that they can see
how the machine sews after the
service or repair.
This sample should contain the
following stitches:
- Straight stitch
- Zigzag stitch
- Running stitch
- Reverse-fed stitch
- Buttonhole
Should the customer have
complained about any specific
stitch, these should also be sewn
on another piece of fabric and
included.
The sample for the customer
must be the technician’s
business card!
9)
BSR foot
Functioning
Even stitching in X/Y directions
10)
Embroidery module
• Test embroidery design or
customer-specific designs if
necessary.
3.4 External cleaning
Caution!
Never use alcohol, petrol, spirits or any other corrosive fluids, or abrasive pastes!
Electrostatic charging may occur during cleaning. To prevent this, use antistatic office-equipment cleaning agents.
We use and recommend “BASF’s SURFACE CLEAN” cleaner It forms a protective film against static charging, and is
suitable for plastic and metallic surfaces.

Service-Manual_artista_630_640_english_V4.01_032069_50_04.doc 20
Chapter 4
Replacing Assemblies
4.1 Removing covers
Before making adjustments, the covers must be removed in the following order:
Head cover:
1. Remove screw (5).
2. Remove head cover.
Attention! The a-640 must have the head cover
refitted when sewing-off.
Rear cover:
1. Remove screw (6).
2. Remove screws (7)
(3 screws).
Remove L-Print
cable.
3. Remove rear cover.
4. The covers are linked
with clips
at the points (B).
Slightly press
against the points to
‘de-clip’ them.
Note:
Be sure not to squash the CFL and buttonhole sensor cables in the head area (A) when refitting the covers.
B
5
B
B
B
A
7
7
6
7