Operation & Calibration of Analytical Balance

1.0 OBJECTIVE
1.1 To lay down a Procedure for Operation & Calibration of Analytical Balance in Quality Control Department.

2.0 SCOPE

2.1 This procedure is applicable for Operation & Calibration of Analytical Balance

3.0 RESPONSIBILITY

3.1 QC Officer or QC Executive

4.0 ACCOUNTABILITY
4.1 QC Manager

5.0 PROCEDURE

5.1 Operating procedure

5.1.1 Place weighing pan on balance, the conical peg centers the pan in the opening in the

base of the weighing chamber also place the draft cover into position.
5.1.2 The two leveling screws are adjusted so that the bubble is in the middle of the circle.
5.1.3 Connect the AC adapter to the specified power supply and plug the AC adapter’s other

terminal into the socket in the back of the balance.
5.1.4 To switch the balance on briefly touch the “On/Off” key after the main power supply of

balance has been switched on.
5.1.5 Check the level of the weighing balance; center the position of the air bubble.
5.1.6 To switch the balance off briefly touch the “On/Off” key and press it until off appears on the display.
5.1.7 Open the sliding glass door by hand.

5.1.8 Place a container or a butter paper on the weighing pan.

5.1.9 Press the →O/T ← key, the display changes to zero, Close the glass door and

then opens again when tarring is complete.

5.1.10 Place the sample to be weighed up to the desired target weight

(to read the weight accurately, the door must be closed)

5.1.11 Stability detector symbol O goes out when stability is achieved, the result is then

stable and the same is printed.

5.2 Care and Maintenance

5.2.1 To switch the balance off briefly touch the “On/Off” key and press it until off appears on the display.

5.2.2 Use a moistened soft cloth or tissue paper to clean the weighing pan and the draft cover.

5.2.3 To remove residues from the weighing chamber use the small artist’s brush.

5.2.4 Do not blow air through the chamber.

5.3 Cleaning

5.3.1 Ensure that the power supply to the instrument is switched off and main cord is removed from supply.

5.3.2 Clean the instrument with a clean dry cloth every day. A wet cloth dipped in 70 % IPA Solution may be
used occasionally. Precaution must be taken to clean the instrument immediately with dry cloth.

5.4 Precautions
5.4.1 Protect from vibrations, thermal fluctuations, sunlight, moisture & air currents.
5.5 Calibration
5.5.1 Switch ‘ON’ the power, then press gently the ‘ON/OFF’ switch on the touch screen to the switch on the balance.
5.5.2 Switch ‘ON’ the printer from the switch on the rear slide of it.
5.5.3 Press and hold the CAL/MENU switch for few seconds. The balance would do internal

calibration automatically, give out the print.
5.6 Daily Calibration of balance
5.6.1 Calibrate the balance daily with the standard weights of 1g, 10g, 100g and 200g individually.
5.6.2 When the balance stabilizes take the print out. Unload the weight and repeat the procedure for all the weights.
5.6.3 Record the observations along with the print out in the respective daily balance calibration data sheet.
5.7 Monthly Calibration of balance
5.7.1 Perform the electronic or self-calibration and check weight calibration as elaborated under “daily calibration check”.
5.7.2 In addition to the daily calibration check and perform the following calibration check.
6.0 ABBREVIATIONS

Abbreviation	Extended Form
QC	Quality Control
SOP	Standard Operating Procedure
mg	milligram

7.0 ATTACHMENTS

Annexure-1 Format for Calibration (Daily)

Annexure-2 Format for Calibration (Monthly)

Annexure-2

Format for Calibration (Monthly)

MONTHLY BALANCE CALIBRATION FORMAT

Name of the Instrument: Weighing Balance Instrument ID No:
Capacity: 220 gm
Date of calibration:
Next Due Date of Calibration:

Sr. No.	Nominal wt.	Actual wt.	Observed wt.	Limit	Remark
1.	20.0 mg	0.0200 gm		± 0.1%
2.	50.0 mg	0.0500 gm		± 0.1%
3.	100.0 mg	0.1000 gm		± 0.1%
4.	200.0 mg	0.2000 gm		± 0.1%
5.	500.0 mg	0.5000 gm		± 0.1%
6.	1.0 gm	1.0000 gm		± 0.1%
7.	10.0 gm	10.0000 gm		± 0.1%
8.	20.0 gm	19.9999 gm		± 0.1%
9.	50.0 gm	49.9999 gm		± 0.1%
10.	100.0 gm	99.9999 gm		± 0.1%
11.	200.0 gm	199.9999 gm		± 0.1%

Remarks: Satisfactory/Not satisfactory

Annexure-1

Format for Calibration (Daily)

DAILY BALANCE VERIFICATION FORMAT

Instrument ID: Date:

Normal weight	Actual weight	Observed reading	Limit	Remark
50.0 mg			± 0.1%
100.0 mg			± 0.1%
200.0 mg			± 0.1%
500.0 mg			± 0.1%
1.0 gm			± 0.1%
10.0 gm			± 0.1%
20.0 gm			± 0.1%
50.0 gm			± 0.1%
100.0 gm			± 0.1%
200.0 gm			± 0.1%