Simple balances were used as early as 5000 B.C. "balance" comes from the Latin word bilanx which means "two pans.“ The modern analytical balance originated during the mid-18th century. The lightweight technique is developed Joseph Black.

In lab for daily weighing

Analytical Balance

Micro balance

Top load balance

100mg – 100g

2.0 mg – 20.0g

1.0 g – 2.0 kg

Analytical Balance

Class-ILow-capacity

& high-sensitivity

balances

Top load balance

100mg – 100g

2mg – 20g

1.0 g – 2.0 kg

Micro balance5µg – 500mgSemi Micro balance

Class-IIBuilt-in weights for analytical balances

& Laboratory weights for routine analytical work

Class-III & IVPrecision balances

&All other weighing

equipments

The Analytical Balance location on a solid bench that is AVT (anti vibration table)

The precision and reproducibility of weighing results is closely associated with the location of the balance.

Stable anti vibration table-has affect on balance for measurement 0.01g or less. Doesn't locate AVT corner of the room-room access through a sliding door.

Location free from air should not be near ovens, furnaces.

The Analytical Balance Room must be temperature and humidity controlled.humidity range 45 - 60% Operatehumidity range <20 – 80<% Never operate

The balance should not be installed near sources of electromagnetic radiation such as radio frequency generators, electric motors, hand held communication devices (including card less telephones and cell phones)The balance should not be adjacent to equipment producing a magnetic field(a magnetic stirrer)

Low humidity increases buildup of static electricity.Never disconnect the balance from the power supply and leave it always switched on / STAND BY mode.

If “OFF” mode: warm-up for 1 hour after switching ‘ON’ the power supply

1. Ensure that the instrument is clean and free from dust with smooth brush (or) lint free duster

2. Silica gel should kept inside the balance chamber

3. Adjusting the bubble at the center4. Before using ensure that the balance is

calibrated5. While weighing any sample use butter paper

& spatula6. Carefully remove any sample residue / spilled

powder7. Take special care during weighing of

liquids8. Before closure ensure that the pan is

empty

Don’t use ….A4 / A3 papers

Date: TimeMake:Model:Ser no:Instrument ID:& Initial weight: (mg/g)

pressing print key

Number of weightsMeanSDMinMaxDif

Tare weight pressing print key

pressing print key ‘STAT” key

Ending Date: Time User:

pressing print key ‘F/CF” key

Sample name:AR No:Test:Sign:

Stamp

Analytical Balance

Micro balance

Top load balance

Daily with secondary standard weight boxMonthly with Primary standard weight box

Daily & Monthly with Primary standard weight box

Weakly with primary standard weight box

Store the weight box in dust free

area

Handling the weights use a

forceps

Use certified weights only,

before use check for the validity

of usage forceps

Analytical Balance

Daily with secondary standard weight boxDaily calibration :

S No Nominal weight Acceptance criteria of actual weight

1 1 g ± 1mg2 10g ± 2mg3 100g ± 20mg4 100mg ± 0.1mg5 10mg ± 0.01mg100mg – 100g

Drift check: check with 20g weight Calculation formula W1-W2W1: before day drift check 20g weight W2: present day drift check 20g weightThe limit is not more than ± 0.0002g

Analytical Balance

Monthly with Primary standard weight boxMonthly calibration : 1. self-calibration2.Calibration with External Calibration standard weights

100mg – 100g

S No Nominal weight Acceptance criteria of actual weight

1 100g ± 20mg2 50g ± 20mg3 20g ± 10mg4 10g ± 2mg5 5g ± 2mg6 2g ± 1mg7 1g ± 1mg8 500mg ± 0.5mg9 200mg ± 0.2mg

10 100mg ± 0.1mg11 50mg ± 0.05mg12 20mg ± 0.02mg13 10mg ± 0.01mg

Analytical Balance

Monthly with Primary standard weight boxMonthly calibration :

100mg – 100g

3.Drift check: check with 20g weight Calculation formula W1-W2W1: before day drift check 20g weight W2: present day drift check 20g weightThe limit is not more than ± 0.0002g4.Uncertainty Test (for five decimal balances):Take 1g standard weight for thisTake at least 10 replicate reading for the same

92

87 6

3

5

410

Calculate the Standard deviationThen calculate the uncertainty as follows

3 X SD-------------

Mass valueIt should be not more than 0.001

Daily calibration :

S No Nominal weight Acceptance criteria of actual weight

1 20 g ± 10mg2 1g ± 1mg3 100mg ± 0.1mg4 50mg ± 0.05mg5 2mg ± 0.002mg

Drift check: check with 1g weight Calculation formula W1-W2W1: before day drift check 1g weight W2: present day drift check 1g weightThe limit is not more than ± 0.0001g

Micro balance

Daily with Primary standard weight box

2.0 mg – 20.0g

Monthly with Primary standard weight boxMonthly calibration : 1. self-calibration2.Calibration with External Calibration standard weights

S No Nominal weight Acceptance criteria of actual weight

1 100g ± 20mg2 50g ± 20mg3 20g ± 10mg4 10g ± 2mg5 5g ± 2mg6 2g ± 1mg7 1g ± 1mg8 500mg ± 0.5mg9 200mg ± 0.2mg

10 100mg ± 0.1mg11 50mg ± 0.05mg12 20mg ± 0.02mg13 10mg ± 0.01mg

Micro balance2.0 mg – 20.0g

Monthly with Primary standard weight boxMonthly calibration : 3.Drift check: check with 20g weight Calculation formula W1-W2W1: before day drift check 20g weight W2: present day drift check 20g weightThe limit is not more than ± 0.0002g4.Uncertainty Test (for five decimal balances):Take 1g standard weight for thisTake at least 10 replicate reading for the same

92

87 6

3

5

410

Calculate the Standard deviationThen calculate the uncertainty as follows

3 X SD-------------

Mass valueIt should be not more than 0.001

Micro balance2.0 mg – 20.0g

Weekly with Primary standard weight box

Weekly calibration :

Nominal weight Actual value Observed reading

Acceptance criteria of actual weight

400g 400.000350 400.00 ± 0.02g200g 200.000170 200.00 ± 0.02g50g 50.000050 49.99 ± 0.02g20g 20.000021 19.99 ± 0.01g5g 4.999998 4.99 ± 0.01g1g 1.000016 1.00 ± 0.01g

Top load balance

1.0 g – 2.0 kg

S No Nominal weight Mass Value of the weight (A)

Observed Value (B) Error 'E' (A-B)

1 100g 100.00009g 99.99968 0.000412 20g 20.000021g 19.99994 0.0000813 10g 10.000019g 9.99993 0.0000894 1g 1.000016g 1.00003 -0.0000145 100mg 100.005g 100.00 0.0056 10mg 10.002g 10.00 0.002

Primary weight box :

S No Nominal weight Mass Value Acceptance criteria

Tolerance Limit

Upper Limit Lower Limit

1 100g 99.999910 ± 20mg 100.01991 99.979912 20g 20.000041 ± 10mg 20.010041 19.9900413 10g 10.000029 ± 2mg 10.002029 9.9980294 1g 1.000036 ± 1mg 1.001036 0.9990365 100mg 100.005 ± 0.1mg 100.105 99.9056 10mg 10.002 ± 0.01mg 10.012 9.992

Secondary weight box :

Don’t weigh like this……

weigh like this !

Special thanks toUshakiran madam

&GLP Team

Your’s