UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
Valid for:
2 years from
approval
Table of Contents
Page
1.
2.
3.
4.
5.
6.
7.
8.
9.
Scope
Objective
Definitions
Responsibility
Procedure
5.1. Diagram of ACB Series ACB-600H® Precision Balance
5.2. Installation
5.3. Configuration
5.4. Operation
5.5. Calibration
5.6 Maintenance
5.7. Flow charts
Precautions
References
Appendices
Revision History
Page 1 of 16
2
2
2
3
3
3
4
4
4
6
6
8
14
14
14
14
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
Valid for:
2 years from
approval
1. Scope
This Standard Operating Procedure (SOP) applies to the staff and students
making use of the ACB Series ACB-600H® Precision Balance in the
laboratories of the Pharmacy Department, University of Malta.
2. Objective
To describe the procedure for the installation, configuration, operation,
calibration and maintenance of the ACB Series ACB-600H® Precision
Balance.
3. Definitions
3.1.
Adjustable Feet: Four circular screws situated at the bottom of the
balance which are adjusted to level the balance out.
3.2.
Calibration: A procedure performed to check a measuring instrument
against an accurate standard to determine any deviations and correct for
errors.
3.3.
Configuration Parameters: A number of different options that are
used to set the balance according to the user’s preferences.
3.4.
Enter Key (or select key): The confirmation or print key. May also be
used to confirm the settings chosen during parameter set up.
3.5.
Light Key (or increment key): To turn the backlight on or off. May
also be used to set increment parameter values during set up.
3.6.
Mode Key: To select between weighing, counting and percentage
mode. May also be used to select the Configuration Parameter Set-up
Mode.
3.7.
On/Off Key: To turn the balance on or off.
3.8.
PCS Key (or next key): To set the initial sample size during parts
counting or percentage weighing. May also be used to select the next
option when performing a parameter set up.
Page 2 of 16
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
3.9.
Valid for:
2 years from
approval
Tare: Allows the balance to display the weight of the sample only and
not the combined weight of the sample and its container.
3.10. Tare Key: To tare the weight of the container during weighing.
3.11. Units Key: To select sample size in counting mode and to select the
desired decimal point in percentage mode.
3.12. Weighing Pan: The area on top of which the material to be weighed is
placed.
3.13. Weighing Unit: The unit in which the weight reading is to be
displayed in i.e. the gram [g], carat [ct], pound [lb], ounce [oz], dram
[dr], grain [gn], troy ounce [ozt], pennyweight [dwt], momme [MM],
jewellery tael [tl. J], Taiwan tael [tl. T], Hong Kong tael [tl. H] and
Indian tola [t].
3.14. Zero Key: To set the initial zero on the display.
4. Responsibility
4.1.
The members of the Department of Pharmacy (staff and students) are
responsible for following this SOP.
4.2.
The designated Laboratory Officer or Laboratory Assistant is
responsible for ensuring that this SOP is followed.
5. Procedure
5.1.
Diagram of ACB Series ACB-600H® Precision Balance
Draft Shield
Weighing Pan
Spirit Level
Adjustable Foot
LCD Display
Function Keys
Page 3 of 16
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5.2.
Installation
5.2.1.
5.2.2.
5.2.3.
5.2.4.
5.2.5.
5.2.6.
5.3.
Place the balance on a stable surface, away from any vibrations.
Place weighing pan gently into pan support.
Turn the adjustable feet at the bottom of the balance clockwise
or anticlockwise until the air bubble in the spirit level is in the
centre of the marked circle.
Insert power supply connector in the plug on the rear of the
balance and plug the power supply into the mains supply.
Press On/Off key to activate the balance.
Wait until balance autotest is finished and a stable zero is
displayed before use.
Configuration
5.3.1.
5.3.2.
5.3.3.
5.3.4.
5.3.5.
5.3.6.
5.3.7.
5.4.
Valid for:
2 years from
approval
Press and hold the MODE Key whilst also pressing the ENTER
Key for 2 seconds.
Wait until the balance displays [CAL].
Press the PCS Key repeatedly until the desired configuration
parameter is reached.
Follow the different steps required for each configuration
parameter as listed in the Configuration Parameters Table
(SOP/PD/303_02/A1).
Press the ENTER Key to confirm the setting and to return the
balance to normal weighing mode.
Press the PCS Key to confirm and continue to another
configuration parameter.
Press the ZERO Key to abandon the changes made and return
the balance to normal weighing mode.
Operation
5.4.1.
Weighing Mode
5.4.1.1.
5.4.1.2.
Ensure that the desired weighing unit is displayed. If
this is not so, use the configuration parameters menu
to change it.
Place material that needs to be weighed on the
weighing pan, add the draft shield and read off value
from the LCD display.
Page 4 of 16
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5.4.1.3.
5.4.1.4.
5.4.1.5.
5.4.1.6.
5.4.1.7.
5.4.2.
If using the tare function, place empty weighing
container on balance, press the TARE key and then
place the material to be weighed in the weighing
container.
Add the draft shield and read off the value from the
LCD display.
Use the tare function repeatedly if necessary.
Press the TARE key with no weight on the scale if
tare function needs to be cancelled.
Press the ZERO key to set display back to zero if the
zero shifts during operation.
Counting Mode
5.4.2.1.
5.4.2.2.
5.4.2.3.
5.4.2.4.
5.4.2.5.
5.4.2.6.
5.4.2.7.
5.4.3.
Valid for:
2 years from
approval
Press the MODE key until ‘pcs’ is displayed on the
lower right hand corner of the display.
Press the UNITS key to select sample size (in
multiples of 10).
Put the same sample number as selected in section
5.4.2.2. on the weighing pan and press the PCS key.
Wait until the ‘C’ symbol disappears to ensure that
the sampling procedure is finished.
Remove sample used to programme the counting
function.
Place desired sample size on the scale and read off
value from the LCD display.
Change back to weighing mode by pressing ENTER.
Percentage Mode
5.4.3.1.
5.4.3.2.
5.4.3.3.
5.4.3.4.
5.4.3.5.
5.4.3.6.
Press the MODE key until ‘100%’ is displayed.
Press the UNITS key to select between 100.0% and
100.00% i.e between 1 and 2 decimal points.
Put item to be considered as 100% (reference
sample) onto the pan and press the PCS key.
Wait until a stable % symbol is displayed to ensure
that the sampling procedure is finished.
Remove reference sample used to programme the
percentage function.
Place desired sample on the pan and read off value
from the LCD display.
Page 5 of 16
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5.4.3.7.
5.5.
Change back to weighing mode by pressing ENTER.
Calibration
5.5.1.
Auto Calibration
5.5.1.1.
5.5.1.2.
5.5.1.3.
5.5.1.4.
5.5.1.5.
5.5.2.
Press the ENTER key for about 3 seconds.
Wait until the display shows the ‘Calibration Weight
Value’ previously set in the configuration parameters
menu.
Put the corresponding standard weight on the
weighing pan.
Wait until the display becomes stable to remove the
standard weight from the balance since calibration is
now being performed automatically.
Do not leave weight on the balance for longer since
an error such as E1 or E4 will be shown on the
display. Clear the error by removing the weight and
pressing the ZERO key.
Calibration with Customised Weight
5.5.2.1.
5.5.2.2.
5.5.2.3.
5.5.2.4.
5.5.2.5.
5.5.2.6.
5.5.2.7.
5.5.2.8.
5.6.
Valid for:
2 years from
approval
Press and hold the MODE Key whilst also pressing
the ENTER Key for 2 seconds, were the balance will
now show [CAL].
Press the ENTER Key.
Press the LIGHT Key and the ENTER Key to key in
the mass weight to be used during the calibration.
Wait until the inputted weight starts flashing on
pressing the ENTER Key for the last time.
Put the same standard weight on the weighing pan.
Wait until display automatically counts back to zero
to indicate that calibration is finished.
Remove standard weight from the weighing pan.
Perform the calibration procedure once again if it is
to be repeated with a different standard weight.
Maintenance
5.6.1.
5.6.2.
Disconnect balance from its power supply before attempting
any cleaning procedures.
Use a clean fine brush to remove any surrounding powder.
Page 6 of 16
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5.6.3.
5.6.4.
Valid for:
2 years from
approval
Use a moistened cloth with a mild cleaning agent for any spilt
material.
Ensure that the air bubble in the spirit level on the front end of
the scale is in the centre of the marked circle.
Page 7 of 16
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5.7.
Flow Chart
5.7.1.
Installation
Start
Place on stable surface, away from any
vibrations
Place pan gently into pan support
Turn adjustable feet until air bubble in
spirit level is in the centre of the
marked circle
Insert power supply connector in plug at
rear of balance and plug power supply to
mains supply
Press On/Off key to activate balance
Wait until balance autotest is finished
and a stable zero is displayed before use
End
Page 8 of 16
Valid for:
2 years from
approval
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5.7.2.
Valid for:
2 years from
approval
Configuration
Start
Press and hold MODE Key and ENTER
Key for 2 seconds
No
[CAL] displayed
Yes
1
Press PCS Key repeatedly until desired
configuration parameter is reached
Follow the different steps required for
each configuration parameter (see
SOP/PD/303_02/A1)
Confirm setting
and continue to
another
configuration
parameter
No
Confirm setting
and return to
weighing mode
Yes
No
No
Abandon changes
and return to
weighing mode
Yes
Press ENTER Key
2
Yes
Press ZERO Key
Press PCS Key
End
2
1
Page 9 of 16
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
Start
5.7.3.
Operation
Valid for:
2 years from
approval
1
No
No
Use balance in
counting mode
Use balance in
weighing mode
3
Yes
4
Yes
Press MODE key until ‘pcs’ is
displayed on the lower right
hand corner of display
No
Press and hold MODE Key and
ENTER Key for 2 seconds
Desired
weighing unit
displayed
Press UNITS key to select
sample size (in multiples of 10)
Press PCS Key repeatedly until
[InitU] is displayed
Put the same sample number as
selected in balance
Press ENTER Key repeatedly
until desired unit is displayed
Yes
No
Using tare
function
Press UNIT Key
Press the PCS key
Press ENTER Key
Wait until the ‘C’ symbol
disappears
Remove sample used to
programme counting function
Place material that needs to be
weighed on pan, add draft
shield and read off value
Yes
Place empty weighing container
on balance
No
ZERO shifted
during operation
2
Place desired sample size on
scale and read off value
displayed
Yes
Press TARE key
No
Change back to
weighing mode
Press ZERO key
Place weighing material in
weighing container
Yes
1
Press ENTER
Add draft shield and read off
value
4
No
Need to cancel
tare function
Use repeatedly if necessary
Yes
1
Press TARE key with no weight
on the scale
2
Page 10 of 16
5
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5
No
Use balance in
percentage
mode
3
Yes
Press MODE key until ‘100%’
is displayed
Press UNITS key to select
between 100.0% and 100.00%
Put item to be considered as
100% onto pan
Press PCS key
Wait until stable ‘100%’ is
displayed
Sampling procedure is finished
Remove sample used to
programme percentage
function
Place desired sample on pan
and read off value from display
No
Change back to
weighing mode
End
Yes
Press ENTER
4
Page 11 of 16
Valid for:
2 years from
approval
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5.7.4.
Valid for:
2 years from
approval
Calibration
Start
No
No
Calibration with
customised weight
Auto Calibration
Yes
Yes
Press ENTER key for about 3 seconds
Press and hold MODE Key and ENTER
Key for 2 seconds
Wait until previously set ‘Calibration
Weight Value’ is displayed
Press ENTER Key
Put corresponding standard weight on
weighing pan
Use the LIGHT and ENTER Keys to key
in the mass weight
Wait until display becomes stable
Wait until inputted weight starts
flashing on pressing ENTER Key for the
last time
Remove the standard weight from
balance as soon as possible
Put same standard weight on pan
No
Error display present
1
Wait until display counts back to zero
Yes
Calibration is finished
Remove standard weight and press the
ZERO Key
Remove standard weight from pan
No
Repeat calibration
with different
standard weight
Yes
Page 12 of 16
End
1
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
5.7.5.
Valid for:
2 years from
approval
Maintenance
Start
No
Balance needs
cleaning
Yes
Disconnect balance from
power supply
No
Any surrounding
powder
Yes
Remove with a clean fine brush
No
Any spilt material
Yes
Remove with a moistened cloth
and mild cleaning agent
No
Bubble level in
the centre of
displayed circle
Yes
End
Page 13 of 16
Manipulate adjustable feet until
air bubble is in the centre of the
marked circle
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
Valid for:
2 years from
approval
6. Precautions
6.1.
6.2.
6.3.
6.4.
6.5.
Do not install balance near extremes of heat and cold.
Protect balance from dust and air draughts.
Keep weighing pan clean and dry to prevent inaccuracies.
Do not move balance during weighing.
Ensure that the maximum tolerated weight of 600g is not exceeded
during weighing procedures and also when using the tare function.
6.6. Do not leave any items on the balance when this is not in use.
6.7. Only use balance if the spirit level is correct.
6.8. Adjust the air bubble in the spirit level each time the balanced is to be
moved to another location.
6.9. Avoid static charge buildup of the material to be weighed and of the
weighing container.
6.10. When transferring balance to a significantly warmer environment,
allow it to acclimatise for approximately 2 hours at room temperature
after it has been disconnected from the mains.
7. References
Adam Equipment. ACB Series Operator’s Manual. United Kingdom: Adam
Equipment CO. Ltd; 2001.
8. Appendices
SOP/PD/303_02/A1 – Configuration Parameters Table
9. Revision History
Version Number
01
02
Page 14 of 16
Amendments/ Reasons for change
Initial Release
Inclusion of subheading titles of
Procedure section in Table of Contents
Update of entire SOP to version 2
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
Valid for:
2 years from
approval
SOP/PD/303_02/A1 – Configuration Parameters Table
Configuration
Parameter
Display
Symbol
Function
Customised Weight
for Calibration
CAL

See section 5.5.2
Initial Weighing
Unit
InitU
To select a desired
weight to be used for
customised calibration
To choose the initial
unit on switching on the
balance

To choose the weighing
units to be enabled

Press the ENTER Key
when
[InitU]
is
displayed
Press the UNIT Key to
choose desired unit
Press the ENTER Key
when
[Unit]
is
displayed
Press the ENTER Key
repeatedly until the
desired weighing unit
is displayed
Press the LIGHT Key
to change from ‘ON’
or ‘OFF’ i.e enable or
disable
Press the ENTER Key
to advance to the next
weighing unit
Press the ENTER Key
when [A. oFF] is
displayed.
Press the LIGHT Key
to choose between 2,
5, 8 minutes or [no] to
disable this feature.
Press the ENTER Key
when
[trn]
is
displayed.
Press the LIGHT Key
repeatedly until the
desired method is
reached
Weighing Units
Unit
Set-Up




Auto Off
Data Transmission
A. oFF
trn
To choose the time
required for the balance
to automatically switch
off after an elapsed
period of time not being
used



To choose the desired
transmission method i.e.
print once when stable

[stb], print once after
pressing Enter key
when stable [tb],
continually print [ser]
or disable this function
[CLOSE]
Page 15 of 16
UNIVERSITY OF MALTA
FACULTY OF MEDICINE & SURGERY
PHARMACY DEPARTMENT
Ref. No.
SOP/PD/303_02
STANDARD OPERATING PROCEDURE
ACB® SERIES ACB-600H
PRECISION BALANCE
Configuration
Parameter
Baudrate
Display
Symbol
rAtE
Stability Range
Filxx
Zero Display Range
Zerox
Auto Zero Recovery
Range
b2 x
Auto-Average
Calculation during
Counting Mode
AC y
Valid for:
2 years from
approval
Function
Set-Up
To choose the desired
baudrate i.e 1200bd,
2400bd, 4800bd and
9600bd

To choose the desired
range of stability for the
balance which can
range from 1 to 15 (the
smaller the value, the
longer the time until the
stability symbol is
displayed on switching
on but the more stable
the balance is)
To choose the desired
range for zero display
for the balance which
can range from 0 to 3


Press the ENTER Key
when
[rAtE]
is
displayed
Press the LIGHT Key
to select the desired
baudrate
Press the LIGHT Key
repeatedly until the
desired stability value
is displayed

Press the LIGHT Key
repeatedly until the
desired zero display
range is displayed

To choose the desired
range for auto zero
recovery for the balance
which can range from 0
to 3
To enable the balance to 
automatically recalculate the unit
weight during counting
mode when the
additional number of
parts added is less than
the number of parts
displayed
Press the LIGHT Key
repeatedly until the
desired auto zero
recovery range is
displayed
Page 16 of 16
Press the LIGHT Key
to choose between [y]
to enable or [n] to
disable this function