JUKI SC-20 Quick start guide

aJUKI
SC-20 SC-120
SC-220 SC-320
ENGINEER'S MANUAL
SC-20
SC-320
No. 1-35-3
1990.7
From the library of: Superior Sewing Machine & Supply LLC

PREFACE
The engineer's manual is written for the technical personnelwho are responsible for the service and maintenance of the
sewing machines. This manual presents detailed explanation of the adjusting procedures, etc. which are not covered by
the INSTRUCTION MANUAL intended for the maintenance personneland operators at a garment factory.
It is advisable to use this engineer's manual is combination with the pertinent INSTRUCTION
MANUAL and PARTS
LIST when servicingthe sewing machines of these models.
OPERATION PRECAUTIONS
Z Oo not put your (irsgers into the thread take-up cover
while (he machine is operating.
4. During operation, be careful not to allow your or any
Other person's head or hands to come close to the
handwheel, V bell, bobbin winder or motor. Also, do
not place anything close to them. Doing so may be
dangerous. i 1_
6. To achieve security, be sure that the power supply
earth wire has been connected before ope'ating the
sewing machine.
1. Keep hands away from (he needle when the
power switch is turned ON or while the machine it
operating.
3. Be sure to turn the power switch OFF before tilling
the machine head or removing the V belt
S. If your machine is provided with a belt cover, finger
guard or any other protectors, do not operate your
machine with any of them removed.
7. No motor sound is heard when the sewing machine is
not operating. So. do not forget to turn the power
OFF at the end of work.
From the library of: Superior Sewing Machine & Supply LLC

i •'* *•'
CONTENTS
1. GENERAL • •••••; •• ^
1-1. Features • • • . 1
2. OPERATION 3
2-1. Name ofpart 3
2-2. Test run ^
2-3. SC-20 Powerindicatorbox ^
2-4. SC-120 Control panel ^
2-5. SC-220 Control panel ®
2-6. SC-320 Control panel 12
3. ADJUSTMENT 21
3-1. Belt tension 21
3-2. Prevention motor vibration (for Ncompany'smotor) 21
3-3. Checkingand correcting the rotational direction of sewingmachine 21
3-4. Pedal 22
3-5. Maximum sewing speed 25
3-6. Auto-lifter 27
3-7. Howto reduce the handlightfrom flickering (for single phaseonly) 28
4. FUNCTIONS 29
4-1. Power supply voltage 29
4-2. Functions selection switches 30
4-3. Increase of control panel functions 44
44. Safety circuit 46
4-5. Connectors for standing work 48
4-6. Production control systemand needle-upstop switch functions 50
5. MAINTENANCE AND INSPECTION 51
5-1. Howto replacethe sensorpotentiometer set 51
5-2. Memory battery charging monitor LED (SC-320 only) 53
5-3. Motor malfunction detector LED 53
54. Solenoid monitor LED 54
5-5. How to replace each circuit board 55
5-6. Troubleshooting 64
5-7. Circuit board installment diagrams 75
5-8. Connector connection diagrams 80
5-9. Type of rating plates for SCseries of the PSC unit 81
5-10. Block diagrams 82
From the library of: Superior Sewing Machine & Supply LLC

1. GENERAL
1-1. Features
1) Use ofan AC servomotor provides the following mqor advantages:
(1) No noise or vibration while the machine is at rest.
(2) The power consumption is 40% to 60% compared with the conventional power consumption.
(3) The motor weight has been almost halved, permitting easier layout change.
(4) The absence ofa clutch (no brake in case ofN company's motor) makes theunit virtually maintenance-fiee.
(H company's brake is good for more than10 years under normal operation.)
Unlike the DC servomotor, there is no bmsh.
2) Pedaloperation features
(1) Youcansetthe maximum sewing speed in400 s.p.m.
stepswith fingertipcontrol according to the type of
operation and your level of proficiency.
(In the conventional unit, the motor pulleyhad to
be changedto alter the maximum sewing speed.)
Further, you canget the samespeedat any time.
(2) The conventional speed limit knobis also provided.
So, by combining the knob with the function
mentioned in(1) above, high-speed playstrokecan
be provided. This eliminatesthe need for large
pedalingforce to maintain high speed,significantly
reducing operator foot fatigue.
(3) The speed acceleration starting pointcanbe adjusted
about 1mm (0.039") by pedal stroke to suit with
each operator.
(4) The minimumspeedfor depressing the front part of
the pedal can be changed(from 200 s.p.m. to 400
s.p.m.).
High-speed'
play stroke
Pedal depression amount
(3) 1mm (0.039 'l
adjustable by ^
pedal stroke >/
/ (4) 400 spm
_t 200 spm
Pedal depression amount
3) Reverse feedstitchingfeatures
(1) As in the conventional model, you can select either the mode in which priority is given to pedaling for the
starting reverse feed stitching orthe mode in which the machine performs nonstop reverse feed stitching at
a preset speed.
(2) The reverse feed stitching speed has been increased from 1,700 s.p.m. to 1,900 s.p.m. (about 12% increase).
Furthermore, the speed canbe adjusted from 1,000 s.p.m. to 3,500 s.p.m., using the variable resistor.
(3) The speed control circuitry has been improved to prevent overrun or 1-stitch error when the reverse feed
stitching speed is changed.
4) Thesoftstart speedhasbeen increased.
The soft start speed for assuring properly interlaced threads ofa starting stitch has been increased from 200 s.p.m.
to 800 s.p.m.
The soft start speed is now adjustable within a range of 200 s.p.m. to 2,000 s.p.m., so you do not have to drop
the speed more than necessary.
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5) Enhanced series with easy upgrading • '•^ ^ ^
Thecontroller comes inthe SC-20, SC-120, SC-220, SC-320 and SC-522 series, andyoucan easily upgrade them
simply by replacing their control panels (excluding the SC-522). ?; > ..
6) A manualcount-downcapabilityhasbeen added.
As an additional capability, the manual count-down capability has been added to the one-touch type reverse feed
switch to provide the control based ofa preset number of stitches.
Description Applications
Count back
When the one-touch type reverse feed switch
is pressed,the preset number of stitches is
counted down.
Sewing pleats
Count back + Thread trim
When the one-touch type reverse feed switch
ispressed,the preset number of stitches is
counted down, and threads are trimmed.
Replaces the reverse feed
stitching at a seam end.
(This feature is especially useful
in a sewing machine for standing
work because the need for
operating the thread trimmer
switch is eliminated.)
7) Even ifa material overlap at sewing startorendis thick, the needle will notbe caught inthe thick overlap.
(After thread trimming, youcanturnthe handwheel inthe reverse direction to bring the needle barup to its
highestposition.)
8) Aconnectorfor standing workhasbeen provided asa standarditem.
9) A terminal for connection to a sewing control system hasbeen provided.
10) The automatic presser foot lifting capability can be added simply by adding the AK auto-lifter and a transistor
circuit board.
11) The control panel is very easy to operate and the slant panel surface makes it easier to see indication on the panel.
12) To ensure easier operation of the control panel, each key has been assigned to only one function.
13) You can setthe lifting duration ofthe Auto-lifter after thread trimming for60 sec. or ten minutes.
(For a sewing machine for standing work, it is advisable to set the lifting duration for ten minutes.)
14) The output transistor has been designed to be a unit circuit board to make ita common part. If any trouble
should occur, the minimum function is assured.
(Example : If the thread trimmer transistor fails, the wiper transistor will work to permit thread trimming and
reversefeed stitching.)
15) The trouble checking feature for the output system (output monitor LED) has been added to the conventional
input system. This enables you to quickly and easily identify defective parts.
16) Reliability
The machine uses only the components which have passed our reliability test conducted on each discrete component.
17) We are planning to provide the following options inthe future:
Sewing controlcounter(oflowcost)
18) The machine controller now can be applied to the control of the ED-1 (cloth edge sensor) (Optional).
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2. OPERATION
2-1. Name of part
O Power switch
oControl box
0Synchronizer
O
L-shaped threadstand
0 PSCbox
0 Max.speed control knob
0Motor
m
0 Pedal
0One-touch type reverse feedswitch
0 Wiper
0 Stand levelling screw(or caster)
0 400 s.p.m.-step speed control knob
0 Connector for standing operation
0 Connector for production control system
- 3
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O Power switch
Power switch for the motor, PSC and control box.
0Control box
Used to make settings for automatic reverse feed stitching, the number ofstitches forpattern sewing orother
sewing conditions.
®Synchronizer
Incorporated in the machine pulley, the synchronizer detects the needle position (up or down) and the se^ymg
speed, then sends a resultant input signal to the main circuit board inthe PSC box. . .
O
L-shaped thread stand
0 PSC box
Comprises a circuitry to control the sewing machine and motor, an output circuitry to operate the elements (thread
trimming solenoid, reverse feed solenoid, etc.), a pedal sensor to detect pedal position, and a power circuitry to
actuate the elements.
0 Max. speed controlknob
Allows analog adjustment of the maximum sewing speed without changing themotor pulley.
0 Motor
Operates the machine at high speed medium speed low speed in response toa signal received from the PSC box.
(AnH company's motoris provided witha brake.)
0 Pedal
The front and back parts ofthe pedal are depressed to control the sewing speed and to actuate the thread trimmer,
presser footlifter (only fora version with AK-31, AK-34), etc.
© One-touch type reverse feed switch
Usedby hand to perform reverse feed stitching.
# Wiper
Wipes the needle thread off the material after thread trimming in response toa wiper signal received from the
PSC box.
0 Stand levelling screw (or caster)
Used to perform adjustment sothatthe stand rests flatly onthe floor to minimize vibration during operation.
0 400 s.p.m.-step speedcontrol knob
This switch has 16 steps from 1to 16in order to digitally setthe maximum speed in400 s.p.m. steps.
0Connector for standing operation
Used fora sewing machine designed for standing operation.
0 Connector for production control system
Usedto connect the machine to a production control system.
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2-2. Test Run ^
1) Operationwhen the power switchis turned ON
When the power switch is turned ON, if the needle isnot initsupperstop position, the machine rotates untilits €?
needle reaches the upper stop position, and then stops with its needle in that position.
If the needle is already in its upper stop position when the power switch is turned ON, the sewingmachine stays
stationary.
'-Uf
2)Pedal operation
(1) Thepedalisoperatesin the foUowing four steps, (exceptfora Version with AK-31, AK-34)
©—
High speed
Low speed
Stop
Thread trimming
High speed
Low speed
Stop (neutral)
Thread trimming
The sewing machine runs at low speed when you depress the front part of the pedal.
The sewing speed changes fromlowto highwhenthe front part of the pedalisfurther depressed.
(However,if the automatic reverse feed stitching switch has been set, the machine willnot mn at high speed
until it completes reverse feedstitching.)
When the pedalis returnedto the neutralposition(stop position),the machine will stop with needle down.
When the backpart of the pedalis depressed, the thread trimmerisactuated and the needlegoesup and
stops in its upper position.
(When the wiperswitchhasbeenset to ON,the wiperisactuated.)
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7^
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(2) In caseof a versionwith AK-31,AK-34
The pedalisoperated in the
following fivesteps:
High speed
Low speed
Stop
Presser foot lifting
Thread trimming
@
High speed
Low speed
Stop (neutral)
Presser foot lifting
Thread trimming
o The sewing machine startsat low speed whenthe front part of the pedalislightly depressed,
o The sewing speed changes from lowto highwhenthe front part of the pedalis further depressed.
(However, if the automatic reverse feed stitching switch has been set,the sewing speed will not change to
highuntil reverse feed stitching iscompleted.)
o When the pedalis returned to the neutral(stop) position,the machine stopswith its needledown,
o When the backpart of the pedal islightly depressed, the presser foot will goup.
o When the backpart of the pedalisfurther depressed, the presser foot comesdown,thread trimmeris
actuated, and the machine stops with its needle up.
(If the wiperswitchhas been set to ON, the wiperis actuated.)
o Between the lowandhigh sewing speedpositions, the machine runsat a speedcorresponding to the pedal
depressionamount. (The speed is infinitely variable.)
o The proper thread trimmingaction willnot be disturbed evenif the pedal is returned to the neutral
position immediatelyafter the machinestarts thread trimming.
At this time, the thread trimmerproperlyoperates even if the front part of the pedalisdepressed, however,
the safetycircuitryisput in operationso that the machine will not mn after thread trimming iscompleted.
Therefore, the pedal must be returned to the neutral position once.
2-3. SC-20 Power Indicator Box
1) Power indicator LED
o Lights up when the power switch is turned ON.
o This light stays ON for a while after the power is turned OFF. It is dangerousto carry out maintenance or
adjustment with the PSC box cover open. Be sure that the LED is OFF before starting maintenance such as
part replacement.
SC- 2 0
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2-4. SC 120 Control panel
1) Control panel
Automatic reverse stitching (for end) indicator
lamp (LED)
•Lights when the ending reverse stitching
switch is ON.
Power indicator lamp (LED)
• Lights up whenthe powerswitchisturned ON.
• Stays ON for a while immediately after the
power switch is turned OFF.
It is dangerous to perform any maintenance
work with the PSC box cover open.
Be sure that the lamp is OFF before per
forming maintenance work such as parts
replacement.
Switch for raising the needle.
• If this switch is turned ON when the machine
stops with its needle down, the needle goes up
and stops in its upper position.
• By depressing the back part of the pedal, the
thread trimmer may be actuated.
(Note that this switch will be invalid when the
needle has been moved down by hand.)
2) Howto use the automatic reverse stitchingpatterns
Automatic reverse
switching (for start)
switchO
Stitching pattern
Automatic reverse
stitching (for end)
switch 0
OFF ON
OFF OFF
OFF
ON
NN
ON
ON
m m
Automatic reverse stitching (for start) indicator
lamp (LED)
•Lights when the starting reverse stitching
switch is ON.
Switches for setting the number of stitches
• These are pushbutton switches for setting the
numbers of stitches for steps A and B.
The setting range is from 0 to 9.
[+]... .Increases the number of stitches
B . . . .Decreases the number of stitches
Automatic reverse stitching (for start) switch
• Used to turn ON or OFF automatic reverse
stitching at sewing start.
• Each time this switch is pressed, it alternately
turns ON or OFF. (This switch is rendered
invalid when the number of stitches for step B
has been set to "0".)
Automatic reverse stitching (for end) switch
• Used to turn ON or OFF automatic reverse
stitching at sewing end.
• Each time this switch is pressed, it alternately
turns ON or OFF. (This switch is rendered
invalid when the number of stitches for step B
has been set to "0".)
m
El m
By combining ON and OFF conditions of automatic reverse
stitching (for start) switch O and automatic reverse stitching
(for end) switch O , four different stitching patterns are
available.
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2-5. SC-220 Control panel
1) Control panel
Automatic reverse stitching (for end) indicator
lamp (LED)
• Lights when the ending reverse stitching switch is ON.
• When pattern 4 has been selected, this lamp does not
light. ^
Automatic reverse stitching (for start) indicator
lamp (LED)
• Lights when the starting reverse stitching switch is ON.
• When pattern 4 has been selected, this lamp does not
light.
Power indicator lamp (LED)
• Lights when the power switch is turned ON.
•Stays ON for a while immediately
after the power
switch is turned OFF.
It is dangerous to perform any maintenance work with
the PSC box cover open.
Be sure that the lamp is OFF before performing
maintenance work such as parts replacement.
Automatic reverse stitching (for start) switch
• Used to turn ON or OFF automatic reverse stitching at
sewing start.
• Each time this switch is pressed, it alternately turns ON
or OFF. (This switch is valid for patterns 1, 2 and 3.
For patterns 1 and 2, the switch is invalid for step B.
For pattern 3, it is invalid when the rotary switch
"SW1. SNUMA—D" in the PSC box has been set to
"0".)
Automatic reverse stitching (for end) switch
• Used to turn ON or OFF automatic reverse stitching at
sewing end.
• Each time this switch is pressed, it alternately turns ON
or
OFF. (This switch is valid for patterns 1, 2 and 3.
The switch is invalid for step C in pattern 1 and step B
in pattern 2. It is also invalid when the rotary switch
"SWI. SNUMA~D" in the PSC box has been set to
"0")
- 8 -
Automatic thread trimming indicator lamp (LED)
•Lights when the automatic thread trimming switch is
ON.
• Ughts whenever pattern 4 has been selected.
• When pattern 1 has been selected, this lamp does not
light.
Pattern indicator lamps (LEDs)
• When a pattern (1 to 4) has
corresponding lamp lights.
been selected, the
Switches for setting the number of stitches
• These are pushbutton switches for setting the numbers
of stitches for steps A to D. The setting range is from 0
to 9.
(When pattern 2 or 3 has been selected, the number of
stitches can be set for 0 to 99 for C and D together.)
^ Increases the numberof stitches
0 Decreases the number of stitches
m
AB AS
ICPj
B B B B
Pattern selector switches
• Used to select one of the four patterns displayed on the
panel.
Switch for raising the needle
• If this switch is turned ON when the machine stops with
its needle down, the needle goes up and stops in its
upper positions.
• By depressing the back part of the pedal, the thread
trimmer may be actuated.
(Note that this switch will be invalid when the needle
has been moved down by hand.)
Automatic thread trimming switch
• This is a selector switch to cause the machine to
automatically trim threads upon completion of the last
sewing step even with the front part of the pedal
depressed.
• For patterns 2 and 3, this switch turns ON or OFF
alternately each time it is pressed.
• For pattern 4, the indicator is always ON regardless of
the switch ON/OFF condition.
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2) How to use each stitching pattern
1. Pattern $>
Automatic reverse
stitching (for start)
switch 0
Stitching pattern
Automatic reverse
stitch (for end)
switch 0
2. Pattern :|>
Automatic reverse
stitching (for start)
switch 0
Stitching pattern
Automatic reverse
stitch (for end)
switch 0
fim
0 0
OFF
ON
OFF OFF
OFF ON
CD CD
OFF OFF
H.
>ۥ
OFF
n
ON
OFF
ON
ON
ON
ON
ON
•
:> •
i>
i»1
CO
f
I."
AB AB
IcdI
e e
%
A/Ci
B ID
A. -B • C D
• Q Q E)
HS ii
(B (9 (9 GO
•JUKI
1. Turn pattern selector O ON.
2. By combining ON and OFF settings of automatic reverse
stitching (for start) switch 0 and automatic reverse
stitching (for end) switch 0 , four different stitching
patterns are available.
3. For the starting automatic reverse stitching, set the
number of stitches using A and B of switch O . For the
ending automatic reverse stitching, set the number of
stitches using C and D of switch O .
(Precaution) Be sure that, when you selecta pattern selector
switch, the corresponding pattern Indicator
lamp lights up.
1. Turn pattern selector switch 0 ON.
2. By combining ON and
OFF conditions of automatic
reverse stitching (for start) switch 0 and automatic
reverse stitching (for end) switch 0 , four different
stitching patterns are available.
3. For bofo starting and ending automatic reverse stitchings,
set the numbers of stitches using A and B of switch O .
4. The numbers of stitches for theintermediate stepscanbe
set within the range of 0 to 99, using C and D of switch
O .
5. When automatic thread trimming switch 0 has been
tumed ON, the thread trimmer will automatically be
actuated upon completion of steps Cand D or the ending
reverse stitching.
6. When automatic thread trimming switch 0 has been
tumedOFF,the machine stopswithits needle down upon
completion of steps C andD. At this time,if you operate
the one-touch type reverse feed switch, the machine mns
at low speed (for compensative stitching). Further, if you
return the pedal to its neutral positionbeforeyou depress
the front part of the pedal again, you can resume sewing
operation regardless of the preset number of stitches.
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3. Pattern :|>
Automatic reverse stitching
(for start) switch ©
OFF
ON
OFF ON
Yn
* CD
ly
CD CD
CD
Stitching pattern
I/n
l/N
AB AB
CD
AB
AB
CD
AB^
AB
CD
AB AB
CD
Automatic reverse stitch
(for end) switch 0
OFF
OFF
ON ON
1. Turn pattern selector switch © ON.
2. By combining ON and OFF conditions of automatic
reverse stitching (for start) switch © and automatic
reverse stitching (for end) switch 0 , four different
stitching patterns are available.
3. Set the numbers of stitches for steps AB and CD within
the range of 0 to 99, usingA to D of switch 0 .
4. Set numbers of stitches N for the starting and ending
automatic reverse stitching steps. (See the setting method
described below.)
5. Upon completion of each step, the machine stops with its
needle down even when you depress the front part of the
pedal. .At this time, if you operate the one-touch type
reverse feed switch, the machine will perform
compensative stitching.
6. If you depress the back part of tlie pedal during
intermediate AB or CD steps, the machine will
immediately trim the threads. If you depress the back
part of the pedal during the last CDstep, the machine will
trim the threads either immediately or upon completion
of the ending automatic reversestitching.
7. When automatic thread trimming switch 0 has been
turned ON, if you depress the front part of the pedal after
completion of the last step, the machine will trim the
threads either immediately or upon completion of the
ending automatic reverse stitching.
8. When automatic thread trimming switch © has been
turned OFF, the machine will stop with its needle down
upon completion
of the last step. When the machine
stops, the pedal is in its neutral position. If you depress
the front part
of the pedal, you can continue sewing
operation. At this time, if you return the pedal to its
neutral position before you depress the back part of the
pedal, the machine will trim the threads either
immediately or upon completion
of reverse stitching.
(Note) For a machine equipped with an Auto-lifter, the
Auto-lifter is actuated when the machine stops with
its needle down upon completion of a step or when
the machine stops with its needle down in
compensative stitching operation.
★ How to set numberof stitchesNfor startingand ending automatic reverse stitching steps
4. Pattern
TP6
S.GND
SNUMA~D
BT SUB
•nCZl'^
JMAX
PNEUF
M400I 301
- 10 -
1. Turn the power switch OFF.
2. Open the PSC box cover.
3. Using a flat-bit screwdriver, set the arrow on rotary switch
(SWl) O on the main circuit board to the desired
number of stitches.
4. Close the PSC box cover.
5. Turn the power switch ON again. This completes the
setting of number of stitches N.
(Note) Both starting and ending automatic reverse stitching
steps will have the same number of stitches.
1. Turn pattern selector switch O ON.
(At this time, the automatic thread trimming indicator
lamp lights up.)
2. Set the numbersof stitchesfor stepsA to D, using A to D
of switch 0 .
3. By depressing the front part of the pedal once, you can
make the machine perform a series of operations from
sewingsteps A to D to trimming the threads.
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^ How to increase the numberof stepsfor Pattern $> (upto 9 steps)
sc. EC
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SCMBT
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TESTB
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SW6
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For the nonnal sewing specification, the number of steps is
four (A, B, C and D) at the maximum. The number of steps
can be increased as many as nine, however, by changing the
setting of the relevant DIP switch on the main circuit board
in the PSC box.
1. Tum OFF the power switch.
2. Open the cover of the PSC box.
3. Set DIP switch (SW44BSRPT) O on the main circuit
board to its ON position.
4. Close the cover of the PSC box.
5. Tum ON the power switch. This completes the setting of
the DIP switch.
Now the sewing specification is as illustrated in the figure.
Set the number of stitches for steps A to C, using A to C of
switch O . Dof switch O is used to specify ^e number
of all the steps.
(Example)
/A-»-B->-C^B => The number of all the steps D=4 \
A^B^C^B^C =>
\ The number of all the steps D = 5 /
(Precaution) If D is set to
"0", all the numbers of stitches
specified for A through C will come to nothing
regardless of the set values for them.
11 -
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2-6. SC-320 Control panel
1) Control panel
+ -I- +
O Power indicator lamp (LED)
• Lights up when the power switch is turned ON.
• Stays ON for a while immediately after the power
switch is turned OFF.
Reverse stitching pattern switch
• Used to select a reverse stitching pattern.
• When this switch is turned ON, lamp 0 comes ON,
while overlapping stitch indicator lamp 0 goes OFF.
Also, all indicator lamps associated to programmed
stitching will go
OFF.
0 Reverse stitehing pattern indicator lamp (LED)
• Lights up when the reverse stitching pattern switch is
turned (DN.
OOverlapping stitch pattern selector switch
• Used
to select an overlapping stitch pattern. When
this switch is turned ON, lamp 0 lights up, while
reverse stitching indicator lamp 0 goes OFF. Also,
ail indicator lamps associated to programmed stitching
will go OFF.
0 Overlapping stitch indicator lamp (LED)
• Lights up when the overlapping stitch pattern switch
is turned ON.
0 Programmed stitching pattern ^ switch
• Used to select the programmed stitching pattern 1.
• When this switch is turned ON, lamp 0 lights up.
O Programmed stitching pattern $> indicator lamp
(LED)
• Lights up when the programmed stitching pattern 1
switch is turned ON.
0Programmed stitching pattern ^ switch
• Usedto select the programmed stitching pattern 2.
• When this switch is turned ON, lamp 0lights up.
o o
0Programmed stitching
pattern ^indicator lamp (LED)
' Lights up when the programmed stitching pattern 2
switch is turned ON.
) Switches for setting the number of stitches
Used to set the number of stitches within the range of
0 to 9 for steps A to D.
"+" : Increases the number of stitches.
" : Decreases the number of stitches.
0 Stitch number displays (LED)
• Indicates the number of stitches for each step (A to D).
0 Automatic reverse stitching (for start) switch
• Used to turn ON or OFF automatic reverse stitching at
sewing start.
• Each time this switch is pressed, it alternately turns
ONor OFF. (When step Bhas been set to "0", the
automatic reverse stitching at sewing start cannot be
set.)
0 AutcMnatic reverse stitching (for start) indicator lamp
(LED)
• Lights up when the automatic reverse stitching (for
start) switch is turned ON.
0 Automatic reverse stitching (for end) switch
• Used to
turn ON or OFF automatic reverse stitching at
sewing end.
• Each time this switch is pressed, it alternately turns
ON or OFF. (When step C has been set to "0", the
automatic reverse stitching for sewing end cannot be
set.)
0Automatic reverse stitehing (for end) indicator lamp
(LED)
• Lights up when the automatic reverse stitching (for
end) switch is turned ON.
From the library of: Superior Sewing Machine & Supply LLC

(E> Stepsetting switch
• Used to make a step change in order to set the number
of stitches, needle stop position, presser foot lifter
ON/OFF, thread trimming or other sewing conditions
for each step in programnied stitching. .
• The step can be changed from 1 to 15.
(If there are steps for which the numbers of stitches
have not been set, only the step of the lowest number
will be displayed.)
• "+" :Increases the step No.
" : Decreases the step No.
I Step display (LED)
Displays a step (1 to 15).
I Step stitch number setting switch
Used to set the number of stitches within the range
of 0 to 99 for each sewing step.
"+" : Increases the number of stitches.
" : Decreases the number of stitches.
When the "+" or side of the switch is held
depressed, the number of stitches continues to increase
or decrease.
I Step stitch number display (LED)
Displays the number of stitches for a step within the
range of 0 to 99.
IMachine stop mode selector switches
Used to select the following machine stop modes at
the time when a step has been sewn:
o The machine will stop with the needle up.
o The machine will stop with the needle down,
o The machine will stop with the presser foot up.
o The machine will stop with the presser foot down,
o The machine will stop after thread trimming.
2) Howto useeachstitdimg pattern
(1) Reversestitching pattern
0 O O O 0 0 O
^ Hi
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^ ^ ^
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0
1. Pressreversestitching pattern switch O •
2. Reverse stitching pattern indicator lamp 0 lights up,
and stitch number displays (LEDs) 0 for steps A to D
indicate the preset numbers of stitches. Also, automatic
reverse stitching (for start) indicator lamp O and
automatic reverse stitching (for end) indicator lamp 0
show the ON and OFF conditions of automatic reverse
stitching (for start) switch 0 and automatic reverse
stitching (for end) switch 0 . -
13
Indicator lamps (LED) for showing the selected machine
stop modes:
The machine will stop with the needle up.
The machine will stop with the needle down.
The machine will stQp with the presser foot up.
The machine will stop with the presser foot down.
The machine will stop after thread trimming.
Step insertion switch
Used to insert a new sewing step in preset sewing steps.
Step deletion switch
Used to delete aparticular one from the preset'sewing
steps.
® Restart switch
• Used to restart sewing a programmed stitch step after
an empty bobbin has been replaced.
Switch for raising the needle
If the machine has stopped with its needle down, the
needle goes up and stops in its highest position when
this switch is turned ON.
'Memory battery exhaustion monitor lamp (LED)
This lamp may light up if the machine has been unused
for an extended period
of time and the battery has
been exhausted.
Automatic reverse
stitching (for start)
switch O
Stitching patterns
Automatic reverse
stitching (for end)
switch O
OFF
OFF
ON
OFF
ON
OFF ON ON
3. To change the numbers of stitches, press the "+" or
" sides of switches 0 for setting the numbers of
stitches located under stitch number displays 0 for
steps A to D.
4. By combining ON and OFF settings of automatic reverse
stitching (for start) switch 0 and automatic reverse
stitching (for end) switch 0 , four different stitching
patterns are available.
From the library of: Superior Sewing Machine & Supply LLC

(2) Oveilapping stitch pattern
9«
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O
GO
51
f T Y
5
El
1. Pressoverlappingstitching pattern switch O .
2. Overlapping stitch pattern indicator lamp O lights up,
and stitch
number displays ©indicate the preset
numbers of stitches.
3. To change the numbers of stitches, press the "+" or
" sides of switches O for setting the numbers of
stitches located under stitch number displays © for
steps A to D.
4. By depressing the front part of the pedal once, you can
cause the machine to sew steps A to D in sequence and
then to actuate its thread trimmer.
(Precaution) The numbers of stitches which have been set
for steps A to D are stored In memory
separately from the numbers of stitches for a
reverse stitching pattern.
★ How to increase the number of stepsfor Pattern (upto 9 steps)
K>
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sc. EC
TESTA
TESTS
TESTP
SBTM/A
WIPON
NFEEO
^eSRPT
HOSAO
MOSAI
HOSBO
HOSBI
SW4
O
REV
SCMBT
EOON
SOFTON
SOFT 1/2
KOSOO
HOSDI
SCMATR
SCMESP
ACTA
ACTB
ACTO
H/N
SW6
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^3) Programmed stitching pattern ^
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Y Y Y
For the normal sewing specification, the number of steps is
four (A, B, C and D) at the maximum. The number
of steps
can be increased as many as nine, however, by changing the
setting
of the relevant DIP switch on the main circuit board
in the PSC box.
1. Turn OFF the power switch.
2. Open the cover of the PSC box.
3. Set DIP switch (SW44BSRPT)
board to its ON position.
4. Close the cover of the PSC box.
5. Turn ON the power switch. This completes the setting of
the DIP switch.
Now the sewing specification is as illustrated in the figure.
Set the number of stitches for steps A to C, usingA to C of
switch O . Dof switch O is used to specify &e number
of all the steps.
(Example)
A-^-B-^-C^B The number of all the steps D = 4
A^B-J-C-^B-^C =>
The number of all the steps D = 5
(Precaution) if D is set to "0", all the numbers of stitches
specified for A through C will come to nothing
regardless of the set values for them.
O
n
o
0
© ©
O on the main circuit
© ©
SjTi. IX[-1
© ©
o
4. The needle-down stop lamp and the presser-foot-up stop
lamp of indicator lamps © (for showing the selected
machine stop modes at the time when a step has been
completed) light up.
5. If any of stitch number displays (A to D) O for the
reverse stitching pattern indicates a number of stitches
other than 4, then you can change it to 4 by pressing
the "+" or side of the correspondingswitch © for
setting the number of stitches.
1. Checkingchanging the programmed stitching
pattern 5>
1. Pressprogrammedstitching pattern 1 switch O .
2. Automatic reverse stitching (for start) indicator lamp ©
and automatic reverse stitching (for end) indicator lamp
© light up, and stitch number displays O for steps
A to D show S] S] SI m .
3. Step display © shows i 111 , and step stitch number
display © shows 12 I 01 .-
14 -
From the library of: Superior Sewing Machine & Supply LLC

The "+" side of switch f
is pressed once at a time
Indication on
display 0
Indication on
display 0
•
Dn
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/ n
I u
Zi
jn
(_ u
I
uI
C
6. Each time the "+" side of step setting switch 0
pressed, the indications will change as illustrated above.
7. If the number of stitches shown on step stitch number
display 0 is different from those given in the table
above, change it by pressing the "+" or side of
switch 0 for setting the number of stitches forastep.
8. If a machine stop mode is different from those given in
the table above, set it using switches 0 for selecting
the machine stop modes.
* Selecting a machine stop mode
I n
I u
n
u
IS
Indicator lamps o
The following lamps light up
°-l-
%
4M
° 1
20
Step 1
Pattern
10
10
Step 4
—O
20
Step 3
Step 2
9. With these settings, you can sew the pattern illustrated
at left by repeating the series of operations Depressing
the front part of the pedal Automatic stop based on the
preset number of stitches Setting the pedal to its
neutral position Depressingthe front part of the pedal.
At this time, the step display indicates the step No. being
sewn, while the stitch number display and the machine
stop mode indicator lamps stay OFF.
You can make the machine stop with its needle up after trimming the threads, or stop with its needle down or up without
trimming the threads, or stop with its presser foot up or down.
How to set the desired machine stop mode
Example 1 : Setting for making the machine stop with
its needle down and presser foot up
°J_
^-5-
P
>€
Press the switches and
1 —I . This will cause the
corresponding indicator lamps to
light up.
Example 2 : Setting for making the machine stop with
its presser foot up after thread trimming
• ^ ° 1
-5-
Press the switches j>g| and
i —i . This will cause the
corresponding indicator lamps to
light up.
In this case, the needle-up stop
lamp and the needle-down stop
lamp stay OFF.
How to release
the thread trimming switch The following two methods are available:
%
•
ir
>§
(T) Press switch L^J again.
This will place the machine in
the needle-down stop mode,
and the corresponding indi
cator lamp will light up. (The
indicator lamp for machine
stop after thread trimming
goes
OFF.)
- 15 -
-5_
>§
ff"
>§
Q) Press the switch ; -J-; or
the switch j . This will
cause the corresponding indi
cator lamps to light up. (The
indicator lamp for machine
stop after thread trimming
goes
OFF.)
From the library of: Superior Sewing Machine & Supply LLC

Adding steps to the programmedstitching pattern 1
The following procedure shows how to add two steps tothe programmed stitching pattern 1in order to sew the pattern
Illustrated below:
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1) Press the "+" side of step setting switch O three
k times.
Indication on the panel
2) Press the switch I—I and the switch I -r-| of
machine stop mode selector switches O •
3) Press the "+" side of step setting switch O once.
Indication on the panel |
4) Keep on pressing the "+" side of step stitch number j ^
setting switch @ until 20 stitches are reached. indication on the panel J
5) Press the switch i—I and the switch
S machine stop mode selector switches O .
6) Press the "+" side of step settingswitch O again.
Indication on the panel
7) Keep on pressing the "+" side of step stitch number
setting switch 0 until 30 stitches are reached. mdication on the panel
8) Press the switch f—i and the switch f^l of
machine stop modeselector switches © .
9) You can set up to 15 steps.
10) By turning ON or OFF automatic reverse stitching
(for start) switch O and automatic
reverse stitching
(for end) switch © , you can make the machine
perform reverse stitching at the sewing start and/or
end.
(This cannot be programmed for each step.)
^ Step 6
Step1120
Indication on the panel
jn
u
Indication on the panel
D n
u
Indication on the panel
20l Steps
I
From the library of: Superior Sewing Machine & Supply LLC

(4) Programmed stitching pattern ^
By pressing programmed stitching pattern 2 switch ® , you can perform check and change just as inthe programmed stitching
pattern 1.
The panel indications and stitching pattern stored in memory are as shown below. a
Automatic reverse stitching (for start) switch @ and automatic reverse stitching (for end) switch O are ON, and stitch
number displays (Ato D) ® will show [3] S [2 H] .
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The "+" side of switch
0 is pressedonce a,
a time
Indication on display
0
•J
J
5
•
•
~sl
Indication on display
0
I D
I U
UI
c n
D u
D C
c n
J u
I D
I L.
n
u
0
i11 D
1
L.
n
0
@ o 0
Indicatorlamps o
The following lamps light up
cr
cr
cr
°4-
4
- 17 -
i-f
'•
1'D1
iX
o
o
140
Stitching pattern
0—6—0
4
12
50
0-< 0
4
12 \4'
50
From the library of: Superior Sewing Machine & Supply LLC