Calibration of Semi-Micro Balance; Purpose :
Calibration of Semi-Micro Balance; The purpose of this SOP is to describe the operation, calibration, cleaning and daily accuracy check of Semi-Micro Balance (Model: MS205DU).
Scope :
This procedure is applicable for Semi-Micro Balance (Model: MS205DU), installed in the quality control laboratory of XX Pharmaceuticals Limited.
Definitions / Abbreviation:
[][]SOP: Standard Operating Procedure
[][]QC: Quality Control
Responsibilities:
Executive/Sr. Executive, QC
[][]To ensure that this procedure is followed.
[][]To ensure daily accuracy check of the balances.
[][]To maintain the records properly as per SOP.
[][]To preserve calibration, daily accuracy check record.
Manager, Quality Control
[][]To ensure that this procedure is kept up to date.
[][]To confirm that the SOP is technically sound and reflects the required working practices.
[][]Arrange training on the SOP to all concerned personnel.
[][]To ensure implementation of the SOP after training.
Head of Quality Assurance
[][]Approval of the SOP
[][]To ensure the overall implementation of the SOP.
Procedure:
General precautions:
[][]Do not move or replace Balance after calibration. If require, calibrate after movement.
[][]Do not place Balance near to heat generating equipment or direct sunlight.
[][]Clean up any spillage in or around the balance immediately after operations.
[][]Proper protective clothing such as safety glasses, gloves and Laboratory coat must be worn during weighing process.
[][]Do not use sharply pointed objects to operate the keyboard of balance.
[][]Do not use cleaning agents which contain solvents or abrasive ingredients.
Calibration of Semi-Micro Balance; Operation:
To start up:
[][]Level and adjust at each time it is moved to a new location. The balance is exactly horizontal when the air bubble is in the middle of the level glass. Adjust the two front leveling feet appropriately until the air bubble comes to rest exactly in the middle of the glass.
[][]Plug the AC adapter and connect the power supply. Connect the printer to the balance.
[][]Switch on the printer using I/O switch.
[][]Press On/Off button to on the Semi-Micro Balance. Display will show 0.00000 g.
[][]Convert the weighing unit from g into mg, press scroll down button if necessary.
[][]Allow the balance to warm up to enable it to adapt itself to the ambient condition.
[][]Press menu button and select ‘BASIC’ by pressing Enter button
[][]Set date, time and unit using -/+ keys and Enter button and save the settings.
[][]Press cancel (C) button to return come out of that ‘BASIC’ option and return to its main menu.
[][]Perform the daily accuracy check at the starting of the day.
Calibration of Semi-Micro Balance; Weighing:
[][]Check the machine is clean and calibrated. Then remove all loads from weighing pan.
[][]When zero (0.00000 g) reading is displayed, the balance is ready for operation. If the display shows greater than or less than zero, press Tare button to tare the balance.
[][]If the balance is not in the weighing mode, press and hold the key down until ‘WEIGHING’ in the display.
[][]Use handle/coupling element for the operation of the draft shield door of the both side of the instrument.
[][]Open right/left/upper sliding window of the instrument.
[][]Place empty container/weighing paper on the pan of the balance. Close the sliding window.
[][]The weight is displayed. Allow the reading to stabilize and wait until the instability detector (O) disappears from the left side of the display and the stability beep sounds.
[][]Press Tare button to tare the balance. When zero (0.00000 g) reading is displayed, the balance is ready for weighing.
[][]The weighing-in aid is a dynamic graphic indicator which shows the used amount of the total weighing range. It can be recognized at a glance when the load on the balance approaches the maximum load.
[][]Add weighing sample (Maximum 220 g) on the container/weighing paper using weighing spoon. Close the sliding window. The net weight is now displayed.
[][]Allow the reading to stabilize and wait until the instability detector disappears from the left side of the display and the stability beep sounds
[][]To get printout of the weight, press print button.
[][]For performing another weighing press tare (O/T) button to tare the balance and follow all steps described above. To increase or decrease digit, press display resolution button.
[][]Finally, press and hold On/Off button ( ) button until ‘SHUT OFF’ shows on the display.
[][]Fill up the Operation Log book for Semi-Micro Balance (as per Annexure-II).
Daily Accuracy Check:
[][]Perform the Internal and External Calibration as per below mention Steps under Calibration.
[][]Take 50 g, 150 g of certified weight and clean it with a soft cloth.
[][]Use tare button to tare the balance before start with a weighing.
[][]Always press button to tare the balance between the interval of one weight to another and observe whether the instability detector (O) disappears from the left side of the display or not and the balance will give a stability beep sounds.
[][]Open one sliding window and place the weights separately at the Centre of the weighing pan, close the sliding window and allow the reading to be stabilized and wait until the instability detector (O) disappear from the left side of the display and the stability beep sounds.
[][]Print the results by pressing print button if necessary.
[][]Record the value of those weights in Log Book for Daily Accuracy Check (as per Annexure-I).
Calibration:
Internal Calibration:
Manual Adjustment with Internal weight:
[][]Press menu button and then press scroll down to go to ‘ADVANCED’ option.
[][]Select ‘ADVANCED’ by pressing Enter button.
[][]Press scroll down button once to select ‘CAL’ option by pressing Enter button.
[][]Then select ‘ADJ. INT’ using scroll down button and then press Enter button.
[][]Press cancel (C) twice and save the settings if required by scrolling down button and press Enter button and then return to its main menu.
[][]Unload weighing pan Press and hold calibration button to execute ‘Internal Adjustment’.
[][]The balance adjusts itself automatically. The adjusting is finished when the message “ADJ.DONE” appears briefly on the display. The balance returns to the last active application and is ready for operation.
[][]After adjustment, the result of the calibration will be printed out automatically.
External Calibration:
Manual Adjustment with External weight:
[][]Follow the previous instruction[Manual Adjustment with Internal weight] for manual adjustment.
[][]Select ‘ADJ. EXT’ by using scroll down and then press Enter button.
[][]Enter the adjustment weight (200g) by using -/+ key for External Calibration and press Enter button.
[][]Then press cancel (C) button twice and save the settings if required by scrolling down button and press Enter button and then return to its main menu.
[][]Unload weighing pan Press and hold calibration button to execute ‘External Adjustment’.
[][]The required predefined adjustment weight value flashes on the display.
[][]Place adjustment certified weight on the center of pan. The balance adjusts itself automatically.
[][]When ‘0.0000 g’ flashes, remove the adjustment weight.
[][]The adjustment is finished when the message ‘ADJ DONE’ appears briefly on the display. The balance returns to the last active application and is ready for operation.
Eccentricity:
[][]Take 50 g, 150 g of certified weight and clean it with a soft cloth.
[][]Use Tare button to tare the balance before start with a weighing.
[][]Always Press button to tare the balance between the interval of one weight to another and observe whether the instability detector (O) disappears from the left side of the display or not and the balance will give a stability beep sounds.
[][]Place 100 g weight at center, Left Rear, Right Rear, right Front, Left Front and center on the pan again separately.
[][]Allow the reading to be stabilized in each time while weighing and wait until the instability detector disappear from the left side of the display and the stability beep sounds.
[][]Press print button separately to print each individual reading in same print page.
Linearity:
[][]Take 50 g, 150 g of certified weight and clean it with a soft cloth.
[][]Use tare button to tare the balance before start with a weighing.
[][]Always press button to tare the balance between the interval of one weight to another and observe whether the instability detector disappears from the left side of the display or not and the balance will give a stability beep sounds.
[][]Place 20 g, 50 g, 100 g, and 200 g on the center of pan separately.
[][]Allow the reading to be stabilized in each time while weighing and wait until the instability detector (O) disappear from the left side of the display and the stability beep sounds.
[][]Press Print button separately to print each individual reading in same print page.
Sensitivity
[][]Take 50 g, 150 g of certified weight and clean it with a soft cloth.
[][]Use tare button to tare the balance before start with a weighing.
[][]Always press button to tare the balance between the interval of one weight to another and observe whether the instability detector disappears from the left side of the display or not and the balance will give a stability beep sounds.
[][]Place 200 g on the center of pan.
[][]Allow the reading to be stabilized in each time while weighing and wait until the instability detector (O) disappear from the left side of the display and the stability beep sounds.
[][]Press Print button separately to print each individual reading in same print page.
Repeatability (200 g):
[][]Take 50 g, 150 g of certified weight and clean it with a soft cloth.
[][]Use tare button to tare the balance before start with a weighing.
[][]Always press button to tare the balance between the interval of one weight to another and observe whether the instability detector disappears from the left side of the display or not and the balance will give a stability beep sounds.
[][]Place 200 g on the center of the pan for ten times separately.
[][]Allow the reading to be stabilized in each time while weighing and wait until the instability detector (O) disappear from the left side of the display and the stability beep sounds.
[][]Press Print button separately to print each individual reading in same print page.
Repeatability (20 g):
[][]Take 50 g, 150 g of certified weight and clean it with a soft cloth.
[][]Use tare button to tare the balance before start with a weighing.
[][]Always press button to tare the balance between the interval of one weight to another and observe whether the instability detector disappears from the left side of the display or not and the balance will give a stability beep sounds.
[][]Place 20 g on the center of the pan for ten times separately.
[][]Allow the reading to be stabilized in each time while weighing and wait until the instability detector (O) disappear from the left side of the display and the stability beep sounds.
[][]Press Print button separately to print each individual reading in same print page.
Result:
[][]Record all the values for calibration in Calibration Information Sheet for Semi-Micro balance (as per Annexure-III).
[][]Perform the Calibration of the Semi-Micro Balance once in every six months.
Cleaning:
[][]Ensure that no liquid comes into contact with the balance and AC adapter.
[][]Remove all objects from the balance.
[][]Clean the pan with soft brush followed by with soft clean cloth.
[][]Clean all of the parts of the balance with clean dry cloth.
[][]Set the parts of weighing pan carefully.
Annexure:
Annexure-I: Log book for Daily Accuracy Check of Semi-Micro Balance
Annexure-II: Operation Log book for Semi-Micro Balance
Annexure-II: Calibration Information Sheet for Semi-Micro balance