Citizen CBM-290 User manual

CITIZEN
Service Manual
Model: CBM-290/291
Line Thermal Printer
Rev. 1.00 Newly issue on June 02, 1998
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CBM-290/291 Service Manual
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INTRODUCTION
This manual describes the disassembly, reassembly, and maintenance procedures of the dot
matrix printer CBM-290/291. It is intended for field maintenance men.
FEATURES
The CBM-290/291 is a thermal line dot type small printer equipped with a line thermal head.
This printer, developed for various data communication terminals, POS terminals, kitchen
printers, is widely available for a variety of applications.
(1) Rack built-in type small line thermal printer
(2) High speed and low noise
(3) High reliability due to long-life printing head and simple mechanism
(4) Serial and parallel interfaces selectable by a DIP switch
(5) Built-in input buffer
(6) Capable of printing bar codes (By a special command)
(7) Equipped with an auto cutter (CBM-291 only)
(8) Capable of dealing with the JIS 1st- and 2nd-level Kanji
(9) External character registration function (94 characters)

CBM-290/291 Service Manual
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CONTENTS
1. HANDLING AND MAINTENANCE OF PRINTER ..........................................................................4
2. SPECIFICATIONS...............................................................................................................................4
2.1 Basic Specifications……………………………………………………………………………………………..4
2.2 Paper Specifications…………………………………………………………………………………………… 5
3. DISASSEMBLY AND REASSEMBLY ................................................................................................6
3.1 Disassembly Procedure..........................................................................................................................6
3.2 Reassembly Procedure.........................................................................................................................10
4. TROUBLESHOOTING ......................................................................................................................11
4.1 Troubleshooting Procedure..................................................................................................................11
4.2 Troubleshooting Guide.........................................................................................................................11
5. SERVICE PARTS LIST......................................................................................................................13
5.1 Pats List for Mechanism......................................................................................................................14
5.2 Disassembly Drawing ..........................................................................................................................16
5.3 Packing Drawing..................................................................................................................................17
5.4 Parts List for Control Board ...............................................................................................................18
5.5 Parts Layout Drawing..........................................................................................................................20
5.5.1 PCB Assy(Parts Side) ..............................................................................................................
20
5.5.2 PCB Assy(Solder Side)............................................................................................................. 21
6. DRAWINGS.........................................................................................................................................22
6.1 Block Diagram......................................................................................................................................23
6.2.1 CBM-290(Without Auto Cutter)..............................................................................................
23
6.2.2 CBM-291(With Auto Cutter) ................................................................................................... 24
6.2 Circuit Diagram....................................................................................................................................25
6.2.1 CBM-290/291............................................................................................................................
25
7. OUTER DIMENTION........................................................................................................................26

CBM-290/291 Service Manual
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See the User’s Manual coming with the printer body.
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Item Description
Printing method Line thermal dot printing system
Printing speed 50 mm/sec. at maximum
Dot density 8 dots/mm (Horizontal and vertical)
Printing digits Font A: 34 digits, Font B: 46 digits
Character size Font A: 1.25 mm x 3.00 mm (10 x 24 + 2 dot space),
Font B: 0.88 mm x 2.13 mm (7 x 17 + 2 dot space),
Kanji: 3.00 mm x 3.00 mm (24 x 24)
Character types Alphenumerals, international characters, JIS 1st- and 2nd-level
Kanji (Kanji for the domestic specifications)
Bar code types UPC-A/E, JAN(EAN) 13 digits/8 digits, ITF, CODE 39, CODE
128, CODE BAR
Line spacing 4.23 mm(1/6 inch), settable by a command
Paper Rolled thermal paper: 58 mm wide x f50 mm or less
Interface Parallel(CENTRONICS) or serial(RS-232C) (Selectable by a DIP
switch)
Input buffer 4 KB
Paper end detection Stops printing when the paper runs out.
Auto loading If new paper is set into the paper inlet, it will be fed
automatically.
Auto cutter (CBM-291 only) Cuts the paper automatically by a command. Either full cut or
partial cut is selectable.
International character set Capable of setting the following 10 countries for specific
character codes by a command.(U.S., French, German, Danish 1
and 2, Swedish, Italian, Spanish, Japanese, Norwegian)
Supply voltage and power
consumption 5 V +/- 5 %, approx. 0.2A at standby and printout; 24 V +/- 5 %, approx. 10 mAat standby and approx. 1.8A at print
(Approx. 6 Aat peak)
Operating temperature 5 to 40 °C, 35 to 85 % RH (No dew condensation)
Storage temperature -20 to 60 °C, 10 to 90 % RH (No dew condensation)
Outer dimensions 106 (W) x 109 (H) x 99 (D) mm
Weight CBM-290: Approx. 460 g (Main body only), CBM-291: Approx.
600 g (Main body only), Fitting: Approx. 50 g
Applicable standards UL, CUL, TUV
EMI VCCI: Class A applicable, FCC: ClassA applicable
Reliability
Printing head life: Pulse resistance --- 50,000,000 pulses (Print
ratio: 12.5 %), Wear resistance --- 30 km (With specified
paper at normal temperature and humidity)
Auto cutter life: 300,000 cuts (CBM-291)

CBM-290/291 Service Manual
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Type : Thermal paper
Paper width : 58 + 0/- 1 mm
Paper thickness : 65 +/- 5mm
Roll diameter : f50 mm or less
Printing face : (Outside of the roll(surface)
Recommended paper : NIPPON PAPER TF50KS-E2C or its equivalent
Core : f12 mm(Inner diameter), f18 mm(Outer diameter)

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1. Remove a cover.
(1) Open the cover.
(2) Remove it, bending one hinge
section outside.
(3) Remove the other hinge section.
2. Remove a rear cover.
(1) Insert a regular screwdriver into
a slot located at the top(or
bottom) of the rear cover.
(2) Raising the end of the regular
screwdriver, remove the rear
cover.
3. Remove a control board.
(1) Using a Phillips screwdriver,
remove two screws(PHT M2.6 x
8).
(2) Disconnect a connector from the
control board.

CBM-290/291 Service Manual
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4. Remove a base plate assembly.
(1) Remove an E-ring from a
shaft.
(2) Pull out the shaft.
(3) Pushing a lever inside,
pull out the base plate
assembly to this side.
·Remove a paper guide from the base
plate assembly.
(1) Pull the paper guide to this side.
(2) Directing this side of the paper
guide upward, pull it out.
·Remove a paper roller from the base
plate assembly.
(1) Using radio pliers, etc., pull out
parallel pins from the paper
roller.
(2) Remove the paper roller.
·Remove an operation panel block
from a base plate.
(1) Using the Phillips screwdriver,
remove screws(PHT, M2.6 x 6)
used to secure the operation
panel block.
(2) Remove the operation panel block
from the base plate.

CBM-290/291 Service Manual
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·Remove the printer mechanism(LT-
282) from the base plate assembly.
(1) Using the Phillips screwdriver,
remove 3 screws(binder, M2.6 x
5) used to secure the printer
mechanism.
(2) Remove the printer mechanism
from the base plate.
·Remove a lever from the base plate
assembly.
(1) Using the Phillips screwdriver,
remove 1 screw(PHT, M2.6 x 5)
used to secure the lever.
5. Remove an auto cutter assembly.
(1) Put the regular screwdriver into
two holes located at the top of the
case and disengage paper feed
guide jaws.
(2) Pull out the auto cutter assembly
to this side.

CBM-290/291 Service Manual
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·Remove the paper feed guide from the
auto cutter assembly.
(1) Pull out the paper feed guide in
an arrow-indicated direction.
·Remove a paper gate from the auto
cutter assembly.
(1) Using the Phillips screwdriver,
remove 4 screws(PHT, M2 x 3)
used to secure the paper gate.
(Note) There are bosses(4 places) on
the cutter side. Pay attention
to them when tightening the
screws at assembly.
6. Remove a roller holder.
(1) Using the Phillips screwdriver,
remove screws(binder, M2.6 x 6).
(2) Remove the roller holder from
the case.
·Remove a roller from the roller holder.
(1) Expose the roller receiving
section of the roller holder to the
outside to remove a roller.

CBM-290/291 Service Manual
- 10 - CITIZEN
7. Remove a cutter earth plate.
(1) Using the Phillips screwdriver,
remove a screw(PHT, M2.6 x 6).
(2) Remove the cutter earth plate
from the case.
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Reassemble each part in the reverse order of the disassembly procedure described in Section 3.1.

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When a trouble occurs, confirm its phenomenon, locate a defective part in accordance with 4.2
Troubleshooting 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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Phenomenon Cause Check Method Remedy
Faulty power supply Check whether 5 V DC is
available. Supply 5 V/24 V DC.
Faulty mounting and
connection of an interface
cable
Check mounting and
connection of the interface
cable.
Connect the interface
cable correctly.
Printing failure
No printing
Faulty printer mechanism Replace the printer
mechanism unit.
Thin printing color Faulty power supply Check whether a 5 V/24
V DC power capacity is
sufficient.
Use the power source
with a sufficient capacity.
Missing dots Foreign substance adhered
to a printing head Check the head for any adhered foreign substance. Dip a cotton swab or soft cloth in ethyl alcohol and
wipe away the foreign
substance.
Faulty power supply Check whether a 5 V/24
V DC power capacity is
sufficient.
Use the power source
with a sufficient capacity.
Badly blurred
printout
Contaminated thermal
head Check the thermal head for any contamination. Dip a cotton swab or soft cloth in ethyl alcohol and
wipe away the foreign
substance.
Bad printing
quality Faulty printing paper Check whether the paper meets the specifications. Replace it with the specified paper.
Faulty connection of a
motor connector Check connection of the connector. Connect the connector correctly.
Faulty power supply Check whether a 5 V/24
V DC power capacity is
sufficient.
Use the power source
with a sufficient capacity.
Paper feed failure
A printing paper
feed motor does
not function or
malfunctions. Faulty printer mechanism Replace the printer
mechanism.

CBM-290/291 Service Manual
- 12 - CITIZEN
Phenomenon Cause Check Method Remedy
Paper feed failure Check whether or not the
printing paper is
jamming or torn and
caught in a paper path.
Eliminate unnecessary
printing paper and re-set
it correctly.
Foreign substance in the
gear Check the platen gear or motor gear of the printer
mechanism for any
foreign substance.
Eliminate the foreign
substance.
The printing paper
is not fed or fed
irregularly.
Broken gear Check the platen gear or
motor gear of the printer
mechanism for breakage.
If broken, replace the
printer mechanism.
Faulty sensor
Does not detect the
printing paper.
Faulty paper sensor Check the window of the
paper sensor for any
foreign substance.
Eliminate the foreign
substance or replace the
printer mechanism.
Motor connector
connection failure Check the connector for connection. Connect the connector properly
Paper jam Check for the printing
paper for jamming. Eliminate the jammed paper.
Faulty auto cutter
The cutter does not
function Faulty auto cutter Replace the auto cutter.
When the trouble
still persists Replace the control board and check whether the
printer functions
properly.
Replace the control
board.
*For the printer mechanism LT-282 and auto cutter AC-120, see the Service Manual separately
provided.

CBM-290/291 Service Manual
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The following table lists the service parts required for maintenance, and so on. The parts
mounted (Surface mount parts) onto the PCBs are excluded from the service parts because it is
difficult to supply them in bulk.

CBM-290/291 Service Manual
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EXPLODED VIEW 1/2
Ref. No. Parts No. Description Q’ty Remarks
1
2
3
4
5
6-1
6-2
6-3
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
30
50
51
52
53
54
55
E 6210-010
E 6200-670
ACS-221
E 8022-080
E 8022-070
E 4019-220
E 5200-310
E 40000210
E 5102-490
E 480-330
E 6233-070
E 6233-080
E 6233-090
E 3
E 4035-810
E 6310-030
E 6220-590
E 6601-350
E 6612-070
23G65662
LT282HA
E 4900-420
E 8029-030
E 8022-090
E 8035-010
E 8032-100
E 2.5
E 70010900
23G57459
23G65751
23G23179
23G22839
23G65930
23G42966
Case
Front panel
Auto cutterACS-221
PF guide
Papet gate
OP case
OP sheet
OP PCB assy
Switch SKHHBV
LED SEL2110S
Shaft
Roller
Roller holder
E ring E3
Earth plate
Rear cover
Paper cutter
Rating lable
Base plate
PF roller
Pin 2x10
Printer LT-282HA
Harness CA212-3S
Lever
Paper guide
Wire band
Caution paper HOT
Head up lever
E ring E 2.5
PCB assy
Screw M2x3
Screw M2.6x5
Screw M2.6x6
Screw M2.6x8
Screw M2.6x6
Screw M3x6-WT
1
1
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
2
1
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1
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1
1
1
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4
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2
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291 only
290 only
291 only

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Ref. No. Parts No. Description Q’ty Remarks
60
61
62
63
65
66
73
74
75
E 4900-460
E 6233-110
23G22294
E 8035-020
29*-GI
29*-MA
29*-CU
Harness CA215-5
Thermal paper
Mounting BRT
Screw M3x12
Wire cramp
Manual
Gift box
Master carton
Cushion
1
1
2
1

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1/2
Ref. No. Parts No. Description CBM-290 CBM-291
IC 1
IC 2
IC 3
IC 4
IC 5
IC 6
TA 1
TA 2
Tr. 1,2
Tr. 3
Tr. 4,5
D 1-9
D 10,11
R 3,31,33
R 15
R 16
R 25,26
R 5
R 4,22,24,38
R 1,2,23,32,34
R 10
R 6-9,12-14
17,19-21,27
28,30
35-37
R 18
R 11
R 29
C 1
C 2
C 3
C 4,6,8,16
C 5,7,10-15
C 17
2020PC-03
E 104-530
E 107-330
E 210-070
E 107-340
E 210-120
E 202-890
E 202-830
E 358-080
E 358-090
E 359-190
E 400-600
E 400-610
E 2010-010
E 2230-210
E 2600-160
E 2600-130
E 2600-170
E 2600-150
CPU 202PC-03
Gate array CBM202LA-00
RAM TC55257DFL-55L
HC-MOS TC74HC04AF
Reset IC M51953BPF
I/FIC MAX232ACSE
Tr.array LB1650
Tr.Array TA8428K
Transistor RN1302
Transistor 2SJ267-FD13
Transistor 2SC2712-GR
Diode FM4003
Diode 1SS193
Chip Re. RK73K2A 100J
Chip Re. RK73K2A 180J
Chip Re. RK73K2A 220J
Chip Re. RK73K2A 330J
Chip Re. RK73K2A 620J
Chip Re. RK73K2A 1KJ
Chip Re. RK73K2A 3.3KJ
Chip Re. RK73K2A 6.8KJ
Chip Re. RK73K2A 10KJ
Chip Re. RK73K2A 33KJ
Chip Re. RK73K2A 30KJ
Chip Re. RK73K2A 82K
El. Cap. 16MR100MF
El. Cap. SRG35VB-100M
C. Cap. GRM40CH101J50
C. Cap. GRM40B102K50
C. Cap. GRM40F104Z50
C. Cap. GRM40B471K50
1
1
1
1
1
1
1
2
1
2
9
2
3
1
1
2
1
4
5
1
17
1
1
1
1
1
1
4
8
1
1
1
1
1
1
1
1
1
2
1
2
9
2
3
1
1
2
1
4
5
1
17
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CBM-290/291 Service Manual
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PARTS LIST
CONTROL BOARD ASSY 2/2
Ref. No. Parts No. Description CBM-290 CBM-291
DS 1
X 1
CN 2
CN 3
CN 4
CN 5
CN 6
OP 1
C 51-77
C 78,80-85
C 79
C 9,86
C 87-90
CP 1
CP 2-6
L 1,4
L 2,3
F 1
F 2
E 5103-230
E 501-400
E 48000780
E 48000615
E 48000635
E 48000785
E 48000350
E 48000775
E 2600-180
E 2600-160
E 2600-150
E 2600-170
E 2600-140
E 2600-190
E 2600-170
E 4009-490
E 4009-480
E 4005-815
E 4005-770
Dip SW. KSD08H
X’tal CSTCS16.00MXOC3
Conn. B16BPH-K-S
Conn. 53047-0410
Conn. 53047-0610
Conn. LY20-40P-DT1-P5
Conn. 5267-04A
Conn. 53047-0510
C. Cap. GRM40CH470J50
C. Cap. GRM40CH101J50
C. Cap. GRM40B471K50
C. Cap. GRM40F104Z50
C. Cap. GRM40B331K50
C. Cap. GRM40F334Z25
C. Cap. GRM40F104Z50
Fe. Beads BLM21A121A
Fe. Beads BLM41P800S
Fuse 251.500
Fuse MQ1.5
1
1
1
1
1
1
1
27
7
1
2
4
1
5
1
1
1
1
1
1
1
1
1
1
27
7
1
2
4
1
5
2
2
1
1

CBM-290/291 Service Manual
- 20 - CITIZEN
5
55
5.
..
.5
55
5 P
PP
Pa
aa
ar
rr
rt
tt
ts
ss
s L
LL
La
aa
ay
yy
yo
oo
ou
uu
ut
tt
t D
DD
Dr
rr
ra
aa
aw
ww
wi
ii
in
nn
ng
gg
g
5.5.1 PCBAssy(Parts Side)
PARTS LAYOUT
CBM-290/291
PARTS SIDE