KERN 120-5DM User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen-Frommern
E-Mail: [email protected]
Tel: 0049-[0]7433- 9933-0
Fax: 0049-[0]7433-9933-149
Internet: www.kern-sohn.com
GB
Service Manual
Electronic Analytical Balances
KERN ABT
Version 1.2 10/2012

2 ABT-SH-e-1012
GB KERN ABT
Version 1.2
Service Manual
Electronic Analytical Balances
Basic Information
Grundlegende Hinweise
The device must be repaired only by trained specialist staff or personnel with
professional formation (such as a repair-specialist accredited by law concerning
verification).
The service manual is obligatory for repair work.
After repair, original conditions of the device have to be restored.
Only original spare parts should be used.
Instructions about conformity-evaluated scales:
Repair must be carried only at 100% compliance with the type approval.
A violation of this specification will result in a loss of the type approval!
After successful repair the balance will have to be reverified before it can be used
again in a statutorily regulated field.
Das Gerät darf nur von geschultem oder beruflich ausgebildetem
Fachpersonal (z. B. eichrechtlich anerkannter Instandsetzer) repariert werden.
Die Serviceanleitung ist bindend für Reparaturen.
Das Gerät muss nach erfolgter Reparatur wieder in den Originalzustand
zurückversetzt werden.
Es dürfen nur Originalersatzteile verwendet werden.
Hinweis zu konformitätsbewerteten Waagen:
Reparatur darf nur in 100% -iger Übereinstimmung mit der
Bauartzulassung erfolgen. Ein Verstoß gegen diese Vorgabe führt zum Erlöschen der
Bauartzulassung!
Nach erfolgreicher Reparatur muss eine Nacheichung erfolgen, um die Waage
wieder im gesetzlich geregelten Bereich verwenden zu können.

ABT-SH-e-1012 3
CONTENTS
1Service Menu ..............................................................................................................4
1.1 Entering the Service Menu...................................................................................4
1.2 Service Menu contents.........................................................................................4
1.3 wAd Map..............................................................................................................5
2Performance Check ....................................................................................................6
2.1 Repeatability ........................................................................................................6
2.2 Corner Load.........................................................................................................6
2.3 Linearity ...............................................................................................................7
2.4 Tilt Error ...............................................................................................................7
3Representative Troubles and Error Messages ............................................................9
3.1 Representative Troubles and Remedies ..............................................................9
3.2 Error Messages..................................................................................................11
3.3 Troubleshooting at Error Message and Interface Failure ...................................12
3.3.1 “CAL E2” Display ........................................................................................12
3.3.2 “CAL E3” Display ........................................................................................14
3.3.3 “CAL E4” Display ........................................................................................15
3.3.4 “CAL d” Display...........................................................................................17
3.3.5 “Err01” Display............................................................................................19
3.3.6 External Input / Output Failure ....................................................................20
4 Parts Replacement ....................................................................................................21
4.1 General Precaution and Information when Disassembling and Assembling ......21
4.2 Balance Internal Inspection................................................................................22
4.3 Replacing Components ......................................................................................28
4.3.1 Replacing Main Board Assy(C42) ...............................................................28
4.3.2 Replacing Interface Board Assy(C41).........................................................29
4.3.3 Replacing Display Board Assy (C40) ..........................................................29
4.3.4 Replacing Weight Loader Assy (B11)..........................................................30
4.3.5 Replacing Unit Assy (2) ..............................................................................30
4.4 Unit Assy (2) Disassembling/Assembling (Force Coil Assy (L4), Detector Board
Assy (U4) Replacement)...............................................................................................31
4.5 Case Assy (3) Components Replacement .........................................................35
5 Adjustments ...............................................................................................................36
5.1 Physical Adjustments of Unit Assy .....................................................................36
5.1.1 Adjusting the Height of Detector Board Assy (U4) ......................................36
5.1.2 Tilt Error Adjustment ...................................................................................36
5.1.3 Balancing Adjustment .................................................................................38
5.1.4 Corner Load Adjustment .............................................................................39
5.1.5 After Physical Adjustments .........................................................................41
5.2 Linearity Adjustment of ABTxx-4M Series Balances ..........................................43
5.2.1 Inputting the Linearity Adjustment Weight Values .......................................43
5.2.2 Linearity Adjustment ...................................................................................43
5.3 Linearity Adjustment of ABTxx-5DM Series Dual-range Balances .....................44
5.4 Calibration of Built-in Weight (PCAL) .................................................................45
5.4.1 Inputting Conventional Mass Values of the External Calibration Weights to
be Used in PCAL.......................................................................................................45
5.4.2 Performing Calibration of the Built-in Weight (PCAL)..................................45
5.5 Span Calibration by Built-in Weight (iCAL).........................................................45
5.6 Using Data Edit Mode (“Edit” in Service Menu)..................................................46
6Structure and Components .......................................................................................47
7Maintenance Parts List and Special Jigs...................................................................51

4 ABT-SH-e-1012
1 Service Menu
For general operations, please refer to the ABT Series instruction manual.
1.1 Entering the Service Menu
1) Set the balance to display the mass.
2) Press and hold the [ON/OFF] key and [1d/10d] key together for 3 seconds.
The mass display remains unchanged.
3) Within 10 seconds, press and hold the [CAL] key and [PRINT] key together
for 3 seconds.
4) The balance model name is displayed to enter the Service Menu mode.
ROM Version 1.01 E2.32 / 1.01 F2.32 and above
(1) Break the seal on base (left side). By pressing the sealing switch on the
display board (a push button on the left from your view of the board),
connect the AC adapter and when “CAL 2” is displayed, release the
switch.
(2) After a short time the display appears “OFF”.
Press the [ON/OFF] key once. Now you are in weighing mode.
(3) Enter the Service Mode following the same procedure as with standard
models (see above, point 2-4).
1.2 Service Menu contents
Pressing the [CAL] key changes the display as follows.
Display Content
Example
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
220-4E
w.int
w.SEt
Lin-Adj
Lin-SEt
1.00-1.00
-End-
EE oUt
CAL (iCAL or
ECAL)
CAL SEt
PCAL SEt
PCAL
-wAd-
-tAd-
Model name
All unit signs are displayed in “trAdE:on” specification.
“g”,”%”,”PCS”,”ct” and “d” unit signs are displayed in “trAdE:Si” specification.
Unit signs are not displayed in “trAdE:oF” specification.
Move built-in weights to initialize position (weight lift up)
Load or unload the built-in weights
Calculate and store the linear coefficient (ABT-5D excluded)
Linear adjustment weight value input (ABT-5D excluded)
Software version No. (Control CPU (Main board) – Application CPU (Display
board))
Exit Service menu
Print out EEPROM content (non-volatile memory)
Selected calibration mode in the user menu
Input value of external weight for calibration
Input value of external weight for built-in weight calibration
Built-in weight calibration
Load adjustment value (see 1.3 wAd Map)
(* Displayed by average mode selected in the user menu.)
Temperature adjustment value
Load adjustment value after temperature correction (see 1.3 wAd Map)

ABT-SH-e-1012 5
(
15
)
-oAd-
(
* Dis
p
la
y
ed b
y
avera
g
e mode selected in the user menu.
)
Load ad
j
ustment value after tem
p
e
r
ature/linear correction
(
see 1.3 wAd
(16) -Lad- Map)
(
* Dis
p
la
y
ed b
y
avera
g
e mode selected in the user menu.
)
(
17
)
-wG-
A
bsolute load value
(
* Dis
p
la
y
ed b
y
avera
g
e mode selected in the user menu.
)
(18) -bAt- Power source voltage AD value
(
19
)
Edit Edit EEPROM data
(20) trAdE:on trAdE:Si Set to export specification. (countries except for Japan)
[
UN IT
]
ke
y
“trAdE:on” All units are usable.
“trAdE:Si” “
g
”,”%”,”PCS” and “ct” are usable.
(
21
)
trAdE:oF Set to domestic s
p
ecification.
(
for Ja
p
an
)
(22) Pun Adj *Control parameter adjustment
* Attention! _Never select this menu item [Pun Adj]. If this adjustment performed, new
linearity adjustment will be necessary.
1.3 wAd Map
In the wAd, 0 Ad, LAd displays, the highest digit (10,000,000) is indicated by the
illumination of each symbol.

6 ABT-SH-e-1012
2 Performance Check
•Leave the power on in mass display and let stand for 8 hours or more.
•Conduct the performance check in a location without drafts, vibration or sudden
changes in room temperature.
•Place weights inside the balance weighing chamber in advance to conduct
performance check without a temperature difference between the weights and
weighing chamber.
•Use long-nose tweezers for loading and unloading weights – do not put hands
inside weighing chamber.
2.1 Repeatability
Load a weight shown in Table 1 (of any preference) on the center of the pan and take
it off 6 times and record each reading.
Determine the repeatability uniformity Rx, Ry of the zero point status and loaded
weight status.
Rx = X max – Xmin : X1, X2… X6
Ry= Ymax – Ymin : Y1, Y2… Y6
2.2 Corner Load
1) Prepare one of each weight shown in Table 1.
2) Place a weight in the pan center (1) and then in each position in order (2)(3)(4)(5) at
distance of 1/2 x pan radius, as shown in Fig. 1. Return the weight to position (1) and
record the displayed values.
3) If the differences between the value measured in the center location and each of the
other locations is within the standard value, the balance cornerload performance is
considered normal.
Example: ((3) position difference) = ((3) display value) – (average value of 2 x (1)
display value)

ABT-SH-e-1012 7
2.3 Linearity
1) Conduct “ECAL” (Span Calibration by External Weights) according to the instruction
manual procedure.
2) Load weights in order shown in Table 1 and record the readings when the display has
stabilized.
3) Calculate the error of each loaded weight.
(Error) = (display value of each loaded weight) – (average zero-point reading before
and after linear adjustment) – (true value of weight (corrected values))
4) If the error is large, conduct ’5.2, 5.3 Linearity Adjustment’.
2.4 Tilt Error
1) Press [TARE] to set display to 0g. (→A)
2) Insert a 1mm thick plate under the fixed foot at the center rear of the balance.
When the display has stabilized record the reading. (→B)
(Error) = B – A
3) If the error is large, conduct ‘5.1.2 Tilt Error Adjustment’.
Table 1: ABT Series Inspection Standards Table
Model 120-4M 220-4M 320-4M
Weight [g] 120 220 320
Minimum display [mg] 0.1 0.1 0.1
Repeatability Standard [mg] 1 1 1
Weight used [g] 100 200 300
Four-corner error
Standard ±0.5 ±1 ±1.5
[
m
g]
Weight 50 100 150
used
[g]
Instrumental error 50g : ±0.5 50g : ±0.5 50g : ±0.5
Standard 50g< : ±1 50g< : ±1 200g : ±1
[mg] 200g< : ±1.5
0 0 0
Weight 120 200 300
used 0 0 0
[g] 20 50 50
50 100 100
100 150 200
0 0 0
120 200 300
0 0 0

8 ABT-SH-e-1012
Model 120-5DM 220-5DM
Weight [g] 120 42 220 82
Minimum display [mg] 0.1 0.01 0.1 0.01
Repeatability Standard [mg] 1 0.3 1 0.3
Weight used [g] 100 40 200 80
Four-corner error
Standard ±0.5 ±0.2 ±1 ±0.3
[
m
g]
Weight used [g] 50 20 100 50
Instrumental error d50g : ±0.5 d5g : ±0.1 d50g : ±0.5 d20g : ±0.2
Standard 50g< : ±1 d20g : ±0.2 50g< : ±1 20g< : ±0.3
[mg] 20g< : ±0.3
Wei
g
ht used [
g
] 0 0 0 0
120 40 200 80
0 0 0 0
20 5 50 20
50 10 100 40
100 20 150 60
00 00
120 40 200 80
0 0 0 0

ABT-SH-e-1012 9
3 Representative Troubles and Error Messages
3.1 Representative Troubles and Remedies
Symptom Probable cause
(Causes are listed not in the order
of probability, but in the order of
ease of checkin
g
.
)
Remedy
Correct power is not supplied. Check the power supply and connect
correctly.
Wrong AC adapter or failure of
A
C ada
p
ter Replace the AC adapter.
Cable
(
C43
)
is disconnected. Connect the Cable
(
C43
)
correctl
y
.
(a)Nothing appears in
the display.
Display Board Assy (C40) is
failed. Replace Display Board Assy.
(b)Missing numbers and/
or s
y
mbols in the dis
p
la
y
.Display Board Assy (C40) is
failed. Replace Display Board Assy.
(c)Keys do not operate. Display Board Assy (C40) is
failed. Replace Display Board Assy.
Pan (5) and/or Pan supporter
ass
y(
4
)
are not ins
t
alled.
Install Pan supporter assy and Pan
correctl
y
.
Pan is loaded exceeding the
wei
g
hin
g
ca
p
acit
y
.
Use the balance within its capacity.
Foreign object is contacting
Pan
(
5
)
and
A
nti-draft rin
g
(
6
)
.
Clear the gap between Pan and
A
nti-draft rin
g
.
Anti-draft plate (11) is not fixed
correctly. Dust exists between
Anti-draft plate and Pan supporter
shaft
(
XX
)
.
Remove dusts and position and fix
Anti-draft plate correctly.
Cable
(
U26
)
is disconnected. Connect Cable
(
U26
)
correctl
y
.
Cable
(
U43
)
is disconnected. Connect Cable
(
U43
)
correctl
y
.
Pt-Ni band (U14) is
twisted/bent/badl
y
soldered.
Replace Pt-Ni band (U14) / Solder
Pt-Ni band correctl
y
.
The hole of Stopper plate (U6) is
contacting with Lever pin (U51). Position and lock Stopper plate
correctly without contacting with Lever
pin.
Lever stopper (U7) and/or
Detector Board assy (U4) are not
correctl
y
positioned.
Position Lever stopper correctly and
adjust hight of Detector Board assy
correctl
y
.
Main Board
A
ss
y
(
C42
)
is failed. Replace Main Board
A
ss
y
.
Force Coil assy (L4) wire break/
earth leak Rplace Force Coil assy.
Force Coil assy (L4) and Magnet
assy (U41) are contacting directly
or with dus
t
s.
Remove dusts and position Force Coil
assy correctly.
(d)"oL" or "-oL" is
displayed.
Unit
A
ss
y
(
2
)
is dama
g
ed. Replace Unit
A
ss
y
.
Linearity adjustment was incorrect.
Inputted calibration weight value
was not correct in linearity
ad
j
ustment.
Perform linearity adjustment correctly
using accurate calibration weights.
Essentially poor repeatability is
causin
g
the s
y
m
p
toms.
Check repeatability and refer to (i)
(
Re
p
ea
t
abilit
y
)
Essentially large drift is causing
the s
y
m
p
toms.
Check drift and refer to (f) (Drift)
(e)Large linearity error
Essentially large corner load error
is causin
g
the s
y
m
p
toms.
Check corner load performance and
refer to
(
h
)
(
Corner load error
)

10 ABT-SH-e-1012
Span calibration has not been
performed correctly. Perform span calibration.
Damaged EEPROM data. Input the data with the Adjustment
S/W.
Unit Assy (2) is damaged. If the error is under XXXX, replace
Unit assembly.
Warm up is insufficient. Warm up sufficiently.
Direct sunlight, or air current from
heater or cooler exist.
Change the balance installation site.
Remove sunli
g
ht / air current.
The installation site has been
chan
g
ed. Warm up sufficiently and perform span
calibration.
The sample or sample container is
magnetically charged, or the
sample is vaporizing or absorbing
moisture e
t
c.
Shield, cover, or demagnetize the
sample.
Cable
(
U26
)
is disconnected. Connect Cable
(
U26
)
correctl
y
.
T
emp Sensor ass
y
(
U47
)
is failed. Replace
T
emp Sensor ass
y
.
Dama
g
ed EEPROM da
t
a. Input the da
t
a with
A
d
j
ustment S/W.
(f)Zero drift, sensitivity
drift are large.
Unit
A
ss
y
(
2
)
is dama
g
ed. Replace Unit
A
ss
y
.
Span calibration has not been
performed correctl
y
.
Perform span calibration.
Warm up is insufficient. Warm up sufficientl
y
.
Level adjustment has not been
done. Adjust level correctly.
The installation site has been
chan
g
ed. Warm up sufficiently and perform span
calibration.
(g)Sensitivity is not
correct.
Dust or dirt is stuck to
Calibration wei
g
ht
(
26
)
.
Clean Calibration weight.
(h)Large corner load
error Unit Assy (2) is damaged. Corner load adjustment on UniBloc /
Re
p
lace Unit assembl
y
(
2
)
.
Effects of air current / vibraiton /
movement of persons. Change the balance installation site.
Remove air current / vibraiton
/
movement of persons. Set
High-stability mode.
The sample or sample container is
char
g
ed with s
t
atic elec
t
ricit
y
.
Cover the sample with metal, such as
foil.
The sample or sample container is
ma
g
neticall
y
char
g
ed.
Demagnetize the sample and
con
t
ainer.
Foreign object is contacting
Pan
(
5
)
and
A
nti-draft rin
g
(
6
)
.
Clear the gap between Pan and
A
nti-draft rin
g
.
Essentially large corner load error
is causin
g
the s
y
mtoms.
Check corner load performance and
refer to
(
h
)
(
Corner load error
)
Essentially large drift is causing
the s
y
mtoms.
Check drift and refer to (f) (Drift)
Cable (U26) is disconnected /
dama
g
ed. Connect Cable (U26) correctly
/
Re
p
lace Cable
(
U26
)
.
Pt-Ni band(U14) is
twisted/bent/badl
y
soldered.
Replace Pt-Ni band / Solder Pt-Ni
band correctl
y
.
Temp Sensor Assy (U47) cable is
badl
y
soldered.
Solder Temp Sensor Assy(U47) cable
correctl
y
.
(i)Poor measurement
repeatability / large
display value fluctuation
/ The stability mark does
not readily appear.
The hole of Stopper plate (U6) is
contacting with Lever pin (U51).
Dus
t
s exist between them.
Clean the hole of Stopper plate and
Lever pin and position and lock
S
t
opper plate correctl
y
.