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

Page 1 of 16

Table of Contents

Page

1. Scope 2

2. Objective 2

3. Definitions 2

4. Responsibility 3

5. Procedure 3

5.1. Diagram of ACB Series ACB-600H® Precision Balance 3

5.2. Installation 4

5.3. Configuration 4

5.4. Operation 4

5.5. Calibration 6

5.6 Maintenance 6

5.7. Flow charts 8

6. Precautions 14

7. References 14

8. Appendices 14

9. Revision History 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

Page 2 of 16

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.

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

Page 3 of 16

3.9. 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

Adjustable Foot

LCD Display

Spirit Level

Function Keys

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

Page 4 of 16

5.2. Installation

5.2.1. Place the balance on a stable surface, away from any vibrations.

5.2.2. Place weighing pan gently into pan support.

5.2.3. 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.

5.2.4. Insert power supply connector in the plug on the rear of the

balance and plug the power supply into the mains supply.

5.2.5. Press On/Off key to activate the balance.

5.2.6. Wait until balance autotest is finished and a stable zero is

displayed before use.

5.3. Configuration

5.3.1. Press and hold the MODE Key whilst also pressing the ENTER

Key for 2 seconds.

5.3.2. Wait until the balance displays [CAL].

5.3.3. Press the PCS Key repeatedly until the desired configuration

parameter is reached.

5.3.4. Follow the different steps required for each configuration

parameter as listed in the Configuration Parameters Table

(SOP/PD/303_02/A1).

5.3.5. Press the ENTER Key to confirm the setting and to return the

balance to normal weighing mode.

5.3.6. Press the PCS Key to confirm and continue to another

configuration parameter.

5.3.7. Press the ZERO Key to abandon the changes made and return

the balance to normal weighing mode.

5.4. Operation

5.4.1. Weighing Mode

5.4.1.1. Ensure that the desired weighing unit is displayed. If

this is not so, use the configuration parameters menu

to change it.

5.4.1.2. Place material that needs to be weighed on the

weighing pan, add the draft shield and read off value

from the LCD display.

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

Page 5 of 16

5.4.1.3. 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.

5.4.1.4. Add the draft shield and read off the value from the

LCD display.

5.4.1.5. Use the tare function repeatedly if necessary.

5.4.1.6. Press the TARE key with no weight on the scale if

tare function needs to be cancelled.

5.4.1.7. Press the ZERO key to set display back to zero if the

zero shifts during operation.

5.4.2. Counting Mode

5.4.2.1. Press the MODE key until ‘pcs’ is displayed on the

lower right hand corner of the display.

5.4.2.2. Press the UNITS key to select sample size (in

multiples of 10).

5.4.2.3. Put the same sample number as selected in section

5.4.2.2. on the weighing pan and press the PCS key.

5.4.2.4. Wait until the ‘C’ symbol disappears to ensure that

the sampling procedure is finished.

5.4.2.5. Remove sample used to programme the counting

function.

5.4.2.6. Place desired sample size on the scale and read off

value from the LCD display.

5.4.2.7. Change back to weighing mode by pressing ENTER.

5.4.3. Percentage Mode

5.4.3.1. Press the MODE key until ‘100%’ is displayed.

5.4.3.2. Press the UNITS key to select between 100.0% and

100.00% i.e between 1 and 2 decimal points.

5.4.3.3. Put item to be considered as 100% (reference

sample) onto the pan and press the PCS key.

5.4.3.4. Wait until a stable % symbol is displayed to ensure

that the sampling procedure is finished.

5.4.3.5. Remove reference sample used to programme the

percentage function.

5.4.3.6. Place desired sample on the pan and read off value

from the LCD display.

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

Page 6 of 16

5.4.3.7. Change back to weighing mode by pressing ENTER.

5.5. Calibration

5.5.1. Auto Calibration

5.5.1.1. Press the ENTER key for about 3 seconds.

5.5.1.2. Wait until the display shows the ‘Calibration Weight

Value’ previously set in the configuration parameters

menu.

5.5.1.3. Put the corresponding standard weight on the

weighing pan.

5.5.1.4. Wait until the display becomes stable to remove the

standard weight from the balance since calibration is

now being performed automatically.

5.5.1.5. 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.

5.5.2. Calibration with Customised Weight

5.5.2.1. Press and hold the MODE Key whilst also pressing

the ENTER Key for 2 seconds, were the balance will

now show [CAL].

5.5.2.2. Press the ENTER Key.

5.5.2.3. Press the LIGHT Key and the ENTER Key to key in

the mass weight to be used during the calibration.

5.5.2.4. Wait until the inputted weight starts flashing on

pressing the ENTER Key for the last time.

5.5.2.5. Put the same standard weight on the weighing pan.

5.5.2.6. Wait until display automatically counts back to zero

to indicate that calibration is finished.

5.5.2.7. Remove standard weight from the weighing pan.

5.5.2.8. Perform the calibration procedure once again if it is

to be repeated with a different standard weight.

5.6. Maintenance

5.6.1. Disconnect balance from its power supply before attempting

any cleaning procedures.

5.6.2. Use a clean fine brush to remove any surrounding powder.

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

Page 7 of 16

5.6.3. Use a moistened cloth with a mild cleaning agent for any spilt

material.

5.6.4. Ensure that the air bubble in the spirit level on the front end of

the scale 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

Page 8 of 16

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

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

Page 9 of 16

5.7.2. Configuration

Start

Press and hold MODE Key and ENTER

Key for 2 seconds

[CAL] displayed

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 return to

weighing mode

Press ENTER Key

Confirm setting

and continue to another

configuration

parameter

End

Abandon changes

and return to

weighing mode

Press ZERO Key

Press PCS Key

1

1

2

2

No No No

No

Yes

Yes

Yes Yes

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

Page 10 of 16

5.7.3. Operation

Start

Use balance in

weighing mode

Place material that needs to be weighed on pan, add draft

shield and read off value

Using tare function

Place empty weighing container

on balance

Press TARE key

Place weighing material in weighing container

Add draft shield and read off value

Need to cancel

tare function

Press TARE key with no weight

on the scale

ZERO shifted

during operation

Press ZERO key

Use balance in

counting mode

Press MODE key until ‘pcs’ is displayed on the lower right

hand corner of display

Press UNITS key to select

sample size (in multiples of 10)

Put the same sample number as

selected in balance

Press the PCS key

Wait until the ‘C’ symbol

disappears

Remove sample used to programme counting function

Place desired sample size on

scale and read off value

displayed

Press ENTER

No

Yes

Yes

Yes

Yes

Yes

No

No

No

No

2

1

1

3

4

Desired

weighing unit

displayed

Press and hold MODE Key and

ENTER Key for 2 seconds

Press PCS Key repeatedly until

[InitU] is displayed

Press ENTER Key repeatedly

until desired unit is displayed

Press UNIT Key

Press ENTER Key

Change back to

weighing mode

Yes

Yes

No

No

4

5

Use repeatedly if necessary

1

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

Page 11 of 16

End

Use balance in percentage

mode

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

Sampling procedure is finished

Wait until stable ‘100%’ is

displayed

Remove sample used to programme percentage

function

Place desired sample on pan

and read off value from display

Change back to

weighing mode

Press ENTER

Yes

Yes

No

4

5

3

No

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

Page 12 of 16

5.7.4. Calibration

Start

Press ENTER key for about 3 seconds

Error display present

End

No

Yes

Yes

Auto Calibration

Wait until previously set ‘Calibration

Weight Value’ is displayed

Put corresponding standard weight on

weighing pan

Remove the standard weight from

balance as soon as possible

Remove standard weight and press the

ZERO Key

No Calibration with

customised weight

Press and hold MODE Key and ENTER

Key for 2 seconds

Press ENTER Key

Use the LIGHT and ENTER Keys to key

in the mass weight

Wait until inputted weight starts flashing on pressing ENTER Key for the

last time

Put same standard weight on pan

Calibration is finished

Remove standard weight from pan

Repeat calibration with different

standard weight

1

No

No

Yes

Yes

Wait until display counts back to zero

Wait until display becomes stable

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

Valid for:

2 years from

approval

Page 13 of 16

5.7.5. Maintenance

Start

Disconnect balance from

power supply

Balance needs

cleaning

Any surrounding

powder

Remove with a clean fine brush

Any spilt material

Remove with a moistened cloth

and mild cleaning agent

Bubble level in

the centre of

displayed circle

End

Manipulate adjustable feet until

air bubble is in the centre of the

marked circle

Yes

No

Yes

Yes

Yes

No

No

No

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

Page 14 of 16

6. Precautions

6.1. Do not install balance near extremes of heat and cold.

6.2. Protect balance from dust and air draughts.

6.3. Keep weighing pan clean and dry to prevent inaccuracies.

6.4. Do not move balance during weighing.

6.5. 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 Amendments/ Reasons for change

01 Initial Release

02 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

Page 15 of 16

SOP/PD/303_02/A1 – Configuration Parameters Table

Configuration

Parameter

Display

Symbol

Function Set-Up

Customised Weight

for Calibration

CAL To select a desired

weight to be used for

customised calibration

See section 5.5.2

Initial Weighing

Unit

InitU To choose the initial

unit on switching on the

balance

Press the ENTER Key

when [InitU] is

displayed

Press the UNIT Key to

choose desired unit

Weighing Units Unit To choose the weighing

units to be enabled

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

Auto Off A. oFF To choose the time

required for the balance

to automatically switch

off after an elapsed

period of time not being

used

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.

Data Transmission trn 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]

Press the ENTER Key

when [trn] is

displayed.

Press the LIGHT Key

repeatedly until the

desired method is

reached

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

Page 16 of 16

Configuration

Parameter

Display

Symbol

Function Set-Up

Baudrate rAtE To choose the desired

baudrate i.e 1200bd,

2400bd, 4800bd and

9600bd

Press the ENTER Key

when [rAtE] is

displayed

Press the LIGHT Key

to select the desired

baudrate

Stability Range Filxx 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)

Press the LIGHT Key

repeatedly until the

desired stability value

is displayed

Zero Display Range Zerox To choose the desired

range for zero display

for the balance which

can range from 0 to 3

Press the LIGHT Key

repeatedly until the

desired zero display

range is displayed

Auto Zero Recovery

Range

b2 x To choose the desired

range for auto zero

recovery for the balance

which can range from 0

to 3

Press the LIGHT Key

repeatedly until the

desired auto zero

recovery range is

displayed

Auto-Average

Calculation during

Counting Mode

AC y To enable the balance to

automatically re-

calculate 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

to choose between [y]

to enable or [n] to

disable this function