Citizen iDP-3550 User manual

Service Manual
DOT MATRIX PRINTER
MODEL iDP3550/3551
Rev. 3.00 Revised on Jan. 25, 2002

iDP3550/3551 Service Manual
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REVISION
Rev.No. Date Comment
Rev.1.00 May 10 1999 Newly issued
Rev.2.00 Sep. 14 2000 Modified the Control Board (PF driver IC etc)
Rev.2.01 Sep. 19 2001 Error correction
Rev.3.00 Jan. 25 2002 Changed page17, page21, page27, page28

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INTRODUCTION
This manual describes the disassembly, reassembly, and maintenance procedures of the dot impact printer
iDP3550/3551. It is intended for field maintenance men.
FEATURES
This is a small-size dot impact printer developed for various data communication terminals, POS terminals,
kitchen-use printers, bank card, terminals, and so on.
Its abundant built-in features allow you to widely use this printer for different applications. Prior to using it,
read and understand this manual thoroughly.
(1) Small size, light weight, and low price
(2) High-speed print (Bi-directional)
(3) Red and black print
(4) Very easy paper loading by the auto loading function
(5) Paper end detecting function
(6) Power supply through an AC adapter

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CONTENTS
1. HANDLING AND MAINTENANCE OF PRINTER...................................................................................... 1
2. SPECIFICATIONS ............................................................................................................................................ 2
2.1 Basic Specifications................................................................................................................................... 2
3. DISASSEMBLY AND REASSEMBLY............................................................................................................ 3
3.1 Disassembly Procedure.............................................................................................................................. 3
3.2 Reassembly Procedure............................................................................................................................. 10
4. TROUBLESHOOTING....................................................................................................................................11
4.1 Troubleshooting Procedure.......................................................................................................................11
4.2 Troubleshooting Guide ............................................................................................................................ 12
5. SERVICE PARTS LIST................................................................................................................................... 17
5.1 Parts List for Mechanism......................................................................................................................... 17
5.2 Disassembly Drawing.............................................................................................................................. 19
5.3 Parts List for PCB Assy ......................................................................................................................... 21
5.3.1 Control PCB Assy 3550-01 (R)/3550-02 (P) ........................................................................... 21
5.3.2 Power PCB Assy 3535-03.......................................................................................................... 25
5.4 Parts Layout Drawing.............................................................................................................................. 27
5.4.1 Control PCB Assy 3550-01 (Serial Interface D-sub 25) ............................................................ 27
5.4.2 Control PCB Assy 3550-02 (Parallel Interface)......................................................................... 28
5.4.3 Power PCB Assy 3535-03 (120V) ............................................................................................. 29
5.4.4 Power PCB Assy 3535-03 (230V) ............................................................................................. 30
6. DRAWING........................................................................................................................................................ 31
6.1 Block Diagram ...................................................................................................................................... 32
6.2 Circuit Diagram....................................................................................................................................... 33
6.2.1 Control PCB Assy 3550-01 (Serial Interface D-sub 25) ............................................................ 33
6.2.2 Control PCB Assy 3550-02 (Parallel Interface)......................................................................... 34
6.2.3 Power PCB Assy 3535-03 (120V) ............................................................................................. 35
6.2.4 Power PCB Assy 3535-03 (230V) ............................................................................................. 36
7. OUTER DIMENSION..................................................................................................................................... 37
7.1 iDP3550................................................................................................................................................... 37
7.2 iDP3551................................................................................................................................................... 38
* For the printer mechanism (DP-400/410), see the separate Service Manual.

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1. HANDLING AND MAINTENANCE OF PRINTER
See the User’s Manual coming with the printer body.

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2. SPECIFICATIONS
2.1 Basic Specifications
Model
Item iDP3550 iDP3551
Printer mechanism Character type: DP-654 series/Graphic type: DP-657series (CITIZEN)
Print method Serial dot impact method (Bidirectional print), 2-pass graphic (Unidirectional
print)
Print width Character type: 63.6 mm/Graphic type: 58.7 mm
Print head 9 pins
Print speed Character type: Approx. 3.6 lines/second/Graphic type: Approx. 3 lines/second
Print columns 40 columns
Character size
Character type: 1.36 mm (W)×2.4 mm (H) (7 dots)
1.36 mm (W)×3.1 mm (H) (9 dots)
Graphic type: 1.20 mm (W)×2.4 mm (H) (7 dots)
1.20 mm (W)×3.1 mm (H) (9 dots)
Character types Alphanumeric, Katakana, International characters, Code page 850, 860, 863, 865,
852, 866, 857, Windows code
Line spacing Character type: 4.23 mm (1/6 inch)/Graphic type: 2.82mm (1/9 inch)
Paper Ordinary paper and non-carbon paper: 76 +/– 0.5 mm(W) ×φ83 mm(OD)
Ink ribbon Special purpose ribbon cartridge:
Red/Black or Single Color (Black or Purple)
Interface Serial(RS-232C), Parallel(CENTRONICS compliant)
Command system CBM mode, STAR mode, ESC/POS mode
The user can select themode with the DIP switch and presetjumpers.
Print function On-line, self-test, and hex. dump print function
Provided by operating the power, LF, and SEL switches.
Input buffer 6K byte or 256 bytes (Selectable with the DIP switch)
Buffer backup function Within 24 hours (After 10 minutes or more of printer operation)
Drawer function 2-drawer, 1-drawer switch
Auto loading function Automatically feeds the paper by several lines when it is inserted.
Paper end detection Stops printing when the paper has run out.
Paper near end detection Stops printing when the paper is running out.(Settable with a command)
Auto cutter None AC-134-E (Capable of partial and full cut)
Winder Special purpose winder AW-3-E (Option) that will be placed separately.
Supply voltage 120 V AC +/- 10 %, 50/60 Hz
230 V AC +/- 10 %, 50/60 Hz
Power consumption Not printing: Approx. 10 W, Printing: Approx. 30 W
Weight Approx. 2.8 kg Approx. 3 kg
Outer dimensions 160(W)×212(D)×194(H) mm 160(W)×212(D)×173(H) mm
Operating temperature and
humidity 0 to 40°, 35 to 85 % RH (No dew condensation)
Storage temperature and
humidity -20 to 60°, 10 to 90 % RH (No dew condensation)
EMI standard U.S.A.: FCC Class-A
Europe: EN55022 Class-A, CE Marking
Safety standard U.S.A., Canada: UL, c-UL Europe: TUV, GS

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3. DISASSEMBLY AND REASSEMBLY
3.1 Disassembly Procedure
1. Removing the Top Cabinet
(1) Remove the printer cover.
(2) Remove the four screws (M3×12) and detach the top cabinet by gently lifting it upward
Top Cabinet

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2. Removing the Chassis Assembly
(1) Remove the top cabinet.
(2) Remove the one screw (M3×6) from the bottom and gently lift the chassis assembly upward.
Pull out the power cable from the bottom cabinet.
3. Removing the Printer Mechanism
(1) Remove the top cabinet.
(2) Remove the two screws (M3×14) .
(3) Disconnect the two connectors and remove the printer mechanism by lifting its connector side up-
ward.
Bottom Cabinet

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4. Removing the Power Board
(1) Remove the chassis assembly and then detach the control board.
(2) Remove the strain relief bushing of the power cable from the chassis with a special tool, round nose
pliers, or a similar tool.
(3) Remove the following four screws and detach the power board by lifting it upward while pulling out
the power switch fromthe chassis.
• Two screws (M4×6) that fasten the transformer
•Onescrew(M3×8) that fastens the heat sink
• One screw with outer-toothed washer (M4×6) that fastens the earth lug of the power cable
Strain Relief Bushing
Power Switch

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5. Removing the PE Sensor Assembly
(1) Remove the chassis assembly and the printermechanism.
(2) Disconnect the one connector from the control board.
(3) Peel off the vinyl tape from the chassis.
(4) Slide the PE sensor assembly in the direction until its hooks come off the chassis, and then re-
move it by turning it in the direction .
Vinyl Tape
Connector
Chassis
Hooks
PE Sensor Assy

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6. Removing the Auto Cutter AC-134
(1) Remove the top cabinet.
(2) Cut the cable tie to set the cable of the auto cutter AC-134, that is fastened to the printer mecha-
nism, free.
(3) Disconnect the one connector from the control board.
(4) Loosen (not remove) the one screw (M2.6×6) and disengage both cutter BK from the cutter BK
mounting holes on the printermechanism chassis to remove the auto cutter.

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7. Removing the Paper Cutter (iDP3550)
(1) While widening both sides of the printer cover as shown by the arrows, push the paper cutter toward
you to disengage it from the two claws.
•Reassembling the Paper Cutter (iDP3550)
While facing the cutter blade away from you, gently insert the paper cutter into the paper cutter mounting
slit on the printer cover until it is securely hooked by the two claws.
Paper Cutter
Printer Cover
Claw
Claw
Printer Cover
Paper Cutter

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8. Assembling the Auto Cutter AC-134
(1) Notes
1) See the User's Manual of AC-130 Auto Cutter for specifications and detailed operations.
2) The printer mechanisms that can mount the auto cutter AC-134 are as follows.
• DP-61*, DP-62*, and DP-65*
(2) Packing List (See Fig. 1.)
1) Auto Cutter Unit AC-130 1 unit
2) Hook L 1 pc.
3) Hook R 1 pc.
4) Cutter BK L 1 pc.
5) Cutter BK R 1 pc.
6) Screw (M2.6×6) 2 pcs.
7) Lock Lever (1 pc) (Attached to AC-130)
8) Paper Gate (1 pc) (Attached to AC-130)
Auto Cutter Unit
Lock Lever
Cutter BK L
Screw M2.6×6
Hook L
Printer Mechanism
Screw M2.6×6
Cutter BK R
Fig. 1
Hook R

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(3) Assembling the Auto Cutter (See Fig. 1)
1) Securely insert the claws of the hook L and hook R into the square holes on the printer mecha-
nism.
2) Securely mount the cutter BK R on the auto cutter unit with the supplied screw (M2.6 ×6).
3) Temporarily mount the cutter BK L on the auto cutter unit with the supplied screw (M2.6×6).
Insert the projections "A" and "B" of the cutter BK L and R into the round holes on the printer
mechanism to mount the auto cutter unit. Engage both ends of the lock lever with the notches
"C" and "D" of the hook L and R, and then s ecurely tighten the screw to fix the cutter BK L.
(4) How to Open the Auto Cutter (See Fig. 2.)
Push the handle and open the auto cutter.
3.2 Reassembly Procedure
Reassemble each part in the reverse order of the disassembly procedure described in Section 3.1.
Handle
Fig. 2

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4. TROUBLESHOOTING
4.1 Troubleshooting Procedure
When a trouble occurs, confirm its phenomenon, locate a defective part in accordance with 4.2 Troubleshoot-
ing Guide, and troubleshoot as described below.
•Phenomenon: Find a trouble phenomenon in this column. If there are multiple phenomena,
take all the corresponding items into consideration. This allows you to specify
a hidden defective part.
•Cause: Lists as many possible causes as possible. Guess a trouble cause out of them
and take its check method to specify the trouble cause.
•Check Method: Describes a check method to specify a trouble cause.
•Remedy: Troubleshoot by taking a remedy described in this column.
By troubleshooting in accordance with the above-mentioned procedure, you can troubleshoot efficiently with
fewer misjudgments.

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4.2 Troubleshooting Guide
•Power Supply Failure
Phenomenon Cause Check Method Remedy
The AC cord is not
connected. Connect the AC cord to the AC outlet.
Not connected to the
terminal block (For
AC230V only)
Connect to the terminal
block.
Check whether any
unspecified power has been
used so far.
Use the specified AC
voltage.
No power
(POWER lamp not
illuminated)
The fuse is gone.
Check whether the
specified fuse is used. Use the specified fuse.
The power is normally
supplied when the cable
is disconnected from the
printer mechanism. (No
operation is done.)
Replace the printer
mechanism.
The power is normally
supplied when the cable of
the power PCB assy is
disconnected from the
control PCB assy.
Replace the control PCB
assy.
The printer mechanism,
control PCB assy, or power
PCB assy is defective.
The phenomenon does not
change after the
above-mentioned check.
Replace the power PCB
assy.
The fuse immediately
goes again after
replacing with new on.
The printer mechanism or
circuit drive power is
abnormal.
With a DC voltmeter,
measure the mechanism
drive voltage and circuit
drive voltage.
Replace the power PCB
assy.
* If the fuse is gone with the specified AC voltage supplied, it is likely that the printer mechanism, control PCB
assy, or power PCB assy is defective. Replace either defective one. Incidentally, check the wiring of the
drawer and interface cable.

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•Printing failure
Phenomenon Cause Check Method Remedy
Faulty AC supply voltage Check whether the
specified AC voltage is
used.
Use the specified AC
voltage.
Faulty mounting or
connection of the printer
mechanism
Check mounting and
connection of the printer
mechanism.
Mount the printer
mechanism properly.
No printing
Faulty printermechanism Replace the printer
mechanism.
Non-recommended paper is
used. Replace it with the specified paper.
Faulty ink ribbon Check wear and tear of the
ink ribbon. Replace the ink ribbon.
Paint printout
Low AC supply voltage Check the supply voltage
with an AC voltmeter. Use the AC voltage within the specified range.
Faulty connection of the
printer mechanism Check whether the printer mechanism cable is
properly connected.
Connect the printer
mechanism cable properly.
Foreign substance is
attached to the print head. Check the head for any adhered foreign substance. Dipacottonswaborsoft cloth in ethyl alcohol and
wipe away the foreign
substance.
Faulty print head Replace the print head or
printer mechanism.
Missing dots
Bent ribbon mask Check whether the ribbon
mask is bent or not. Correct the ribbon mask to remove unwanted bending.
Faulty AC supply voltage Check whether the
specified AC voltage is
used.
Use the specified AC
voltage.
Badly blurred
printout
Foreign substance is
attached to the print head. Check the head for any adhered foreign substance. Dipacottonswaborsoft cloth in ethyl alcohol and
wipe away the foreign
substance.
Faulty paper Check whether the paper
meets the specifications. Replace it with the specified paper.
Faulty ink ribbon Check wear and tear of the
ink ribbon Replace the ink ribbon.
Bad printing quality
Low AC supply voltage Check the AC supply
voltage with an AC
voltmeter.
Use the AC voltage within
the specified range

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•Faulty carriage mechanism
Phenomenon Cause Check Method Remedy
Abnormal sound Faulty connection of the
head connector Check the connection of the head connector. Connect the connector properly.
ERROR lamp
illuminated The print head does not move to the home position
at power-on, or it does not
move.
Check for any foreign
substance within a movable
range or any wear of the
gear, etc.
Replace the print head or
printer mechanism.
The paper is jamming. Turn off the power once,
and then on it again. If there is a shear in printing, replace the printer
mechanism.
Faulty AC supply voltage Check whether the
specified AC voltage is
supplied with an AC
voltmeter.
Use the specified AC
voltage.
Foreign substance in the
gear Remove the printer mechanism and check for
any foreign substance
caught in the gear, head
motor gear, or print head
moving part.
Eliminate the foreign
substance.
Shear in printing
Broken gear Remove the printer
mechanism and check for
any breakage of the gear,
head motor gear, or print
head moving part.
If broken, replace the
printer mechanism.

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•Paper feed failure
Phenomenon Cause Check Method Remedy
Faulty connection of the
motor connector Check connection of the motor connector. Connect the connector correctly.
Defective motor Measure the supply
voltage with a DC
voltmeter or oscilloscope.
If the supply voltage is
normal, replace the motor
(printer mechanism).
Paper feed failure
(Paper jam) Check whether or not the paper is jamming or torn
and caught in the paper
path.
Eliminate unnecessary
paper in the paper path and
set paper properly.
Low AC supply voltage Check the AC supply
voltage with an AC
voltmeter.
Use the specified AC
voltage.
Foreign substance in the
gear Remove the printer mechanism and check for
any foreign substance
caught in the gear ormotor
gear.
Eliminate the foreign
substance.
Paper is not fed or fed
irregularly
Broken gear Remove the printer
mechanism and check for
any breakage of the gear or
motor gear.
If broken, replace the
printer mechanism.
•Faulty sensors
Phenomenon Cause Check Method Remedy
Faulty paper sensor Replace the printer
mechanism and check if the
replaced one functions
properly.
Check whether the ERROR
lamp flickers when paper is
out.
Replace the printer
mechanism.
Does not detect
presence of paper.
Foreign substance, etc.
caught by the sensor Check for any foreign sub- stance. Eliminate the foreign substance.
Faulty paper near-end sen-
sor Replace the paper near-end sensor.
Faulty connection of the
paper near-end sensor Check connection of the connector. Connect the connector cor- rectly.
Does not detect paper
near-end status.
Foreign substance, etc.
caught by the sensor Check for any foreign sub- stance. Eliminate the foreign sub- stance.
•If the no-paper condition is not detected while the printer is running out of the recording paper, it will print
without the paper, leading to a trouble of the head, and so on.

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•Faulty auto cutter (iDP3551 only)
Phenomenon Cause Check Method Remedy
Faulty connection of the
motor connector Check connection of the motor connector. Connect the connector cor- rectly.
Faulty AC supply voltage Check whether the speci-
fied AC voltage is supplied
with an AC voltmeter.
Use the specified AC volt-
age.
Defective motor Measure the supply
voltage with a DC voltme-
ter or oscilloscope.
If the supply voltage is
normal, replace the motor
(auto cutter).
Does not cut paper.
Paper feed failure
(Paper jam) Check whether or not the paper is jamming or torn
and caught in the paper
path.
Eliminate unnecessary pa-
per in the paper path and
set paper properly.
•Faulty winder (When AW-3 is used)
Phenomenon Cause Check Method Remedy
Paper end is not correctly
inserted into the slit of the
winder reel.
Insert paper into the slit
correctly.
Faulty connection of the
motor connector Check connection of the motor connector. Connect the connector correctly.
Faulty AC supply voltage Check whether the specified
AC voltage is supplied with
an AC voltmeter.
Use the specified AC
voltage.
Paper feed failure
(Paper jam) Check whether or not the paper is jamming or torn
and caught in the paper
path.
Eliminate unnecessary
paper in the paper path and
set paper properly.
Does not wind paper.
Defective motor Measure the supply volt-
age with a DC voltmeter or
oscilloscope.
If the supply voltage is
normal, replace the motor
assy AW.