Ref.. Table of Contents Page 1. Scope 2 2. Objective 2 3. Definitions 2 4. Responsibility 3 5. Procedure 3 6. Precautions 14 7. References 14 8. Appendices 14 9. Revision History 14 Original Authorised Copy for: Reading Copy Written by: Reviewed by: Approved by: Signature/Date: Signature/Date: Signature/Date: Page 1 of 16
Ref.. 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
Ref.. 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 Spirit Level Weighing Pan Adjustable Foot Function Keys LCD Display Page 3 of 16
Ref.. 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 (/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. Page 4 of 16
Ref.. 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. Page 5 of 16
Ref.. 5.5. Calibration 5.4.3.7. Change back to weighing mode by pressing ENTER. 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. Page 6 of 16
Ref.. 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. Page 7 of 16
Ref.. 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
Ref.. 5.7.2. Configuration Start Press and hold MODE Key and ENTER Key for 2 seconds [CAL] displayed 1 Press PCS Key repeatedly until desired configuration parameter is reached Follow the different steps required for each configuration parameter (see /A1) Confirm setting and return to weighing mode Confirm setting and continue to another configuration parameter Abandon changes and return to weighing mode Press ENTER Key Press ZERO Key 2 Press PCS Key End 2 1 Page 9 of 16
Ref.. Start 5.7.3. Operation 1 Use balance in weighing mode Use balance in counting mode 3 4 Desired weighing unit displayed Press and hold MODE Key and ENTER Key for 2 seconds Press MODE key until pcs is displayed on the lower right hand corner of display Press PCS Key repeatedly until [InitU] is displayed Press UNITS key to select sample size (in multiples of 10) Press ENTER Key repeatedly until desired unit is displayed Put the same sample number as selected in balance Press UNIT Key Press the PCS key Press ENTER Key Wait until the C symbol disappears Using tare function Place empty weighing container on balance 2 Place material that needs to be weighed on pan, add draft shield and read off value ZERO shifted during operation Remove sample used to programme counting function Place desired sample size on scale and read off value displayed Press TARE key Place weighing material in weighing container Add draft shield and read off value Press ZERO key 1 Change back to weighing mode Press ENTER 5 4 Need to cancel tare function Use repeatedly if necessary Press TARE key with no weight on the scale 2 1 Page 10 of 16
Ref.. 5 3 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 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 Change back to weighing mode End Press ENTER 4 Page 11 of 16
Ref.. 5.7.4. Calibration Start Auto Calibration Calibration with customised weight 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 Remove the standard weight from balance as soon as possible Wait until inputted weight starts flashing on pressing ENTER Key for the last time Put same standard weight on pan Error display present 1 Wait until display counts back to zero Remove standard weight and press the ZERO Key Calibration is finished Remove standard weight from pan Repeat calibration with different standard weight End 1 Page 12 of 16
Ref.. 5.7.5. Maintenance Start Balance needs cleaning Disconnect balance from power supply 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 Manipulate adjustable feet until air bubble is in the centre of the marked circle End Page 13 of 16
Ref.. 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 /A1 Configuration Parameters Table 9. Revision History Version Number Amendments/ Reasons for change 01 Initial Release Page 14 of 16
Ref.. /A1 Configuration Parameters Table Configuration Parameter Display Symbol Function Set-Up Customised Weight for Calibration Initial Weighing Unit CAL InitU To select a desired weight to be used for customised calibration To choose the initial unit on switching on the balance Weighing Units Unit To choose the weighing units to be enabled 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 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] See section 5.5.2 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 Page 15 of 16
Ref.. Baudrate rate To choose the desired baudrate i.e 1200bd, 2400bd, 4800bd and 9600bd 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) Zero Display Range Zerox 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 Auto Zero Recovery Range Auto-Average Calculation during Counting Mode b2 x AC y 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 Press the LIGHT Key to choose between [y] to enable or [n] to disable this function Page 16 of 16