Description
The below table is a UKAS (United Kingdom Accreditation Service) guideline for selecting the most appropriate calibration weight for your weighing scale.
|
Weighing Scale Resolution |
||||||
|
Weighing Scale Capacity |
100g | 10g | 1g | 100mg | 10mg | 1mg |
|---|---|---|---|---|---|---|
| Up To 500g | M3 | M3 | M3 | M2 | F2 | E2 |
| Up To 1Kg | M3 | M3 | M3 | M1 | F1 | E1 |
| Up To 5Kg | M3 | M3 | M2 | F2 | E2 | |
| Up To 10Kg | M3 | M3 | M1 | F1 | E1 | |
| Up To 50Kg | M3 | M2 | F2 | E2 | ||
| Up To 100Kg | M3 | M1 | F1 | |||
| Up To 500Kg | F2 | E2 | ||||
Technical Specification
Each classification specifies maximum error discrepancies from a nominal value. The classification given to a calibration weight also depends upon its material, density, corrosion resistance, hardness, wear resistance, brittleness, magnetic properties, construction, and surface finish.
| M2 | |
|---|---|
| Notation | Precision weights for testing, calibrating and adjusting trade balances. |
| Error Discrepancy | The maximum error discrepancy from nominal value at 1 kg is 160mg. |
| Material | 1g to 2kg Brass, 5kg to 20kg Cast Iron. |
Other OIML Classifications
| E1 | |
|---|---|
| Notation | Weight standards of the highest accuracy class, mostly only used as reference standards for metrological services. |
| Error Discrepancy | The maximum error discrepancy from nominal value at 1Kg is 0.5mg. |
| Material | Stainless Steel. |
| E2 | |
| Notation | The most accurate test or adjusting weights for high resolution, high precision weighing scales. |
| Error Discrepancy | The maximum error discrepancy from nominal value at 1 kg is 1.6 mg. |
| Material | 1mg to 5mg Aluminium, 10mg to 500mg Nickel Silver, 1g to 20kg Stainless Steel. |
| F1 | |
| Notation | High precision weights suitable for testing, calibrating and adjusting most high precision weighing scales. |
| Error Discrepancy | The maximum error discrepancy from nominal value at 1 kg is 5 mg. |
| Material | 1mg to 5mg Aluminium, 10mg to 500mg Nickel Silver, 1g to 20kg Nickel Plated Brass. |
| F2 | |
| Notation | High precision weights suitable for very accurate precision balances. Ideal weight classification for weighing applications involving high value commercial transactions, e.g. precious stones. |
| Error Discrepancy | The maximum error discrepancy from nominal value at 1 kg is 16mg. |
| Material | 1mg to 5mg Aluminium, 10mg to 500mg Nickel Silver, 1g to 20kg Stainless Steel. |
| M1 | |
| Notation | Precision weights for trade weighing scales. |
| Error Discrepancy | The maximum error discrepancy from nominal value at 1 kg is 50mg. |
| Material | 1mg to 5mg Aluminium, 10mg to 500mg Nickel Silver, 1g to 20kg Brass. |
| M3 | |
| Notation | Trade weights for everyday use with weighing scales. |
| Error Discrepancy | The maximum error discrepancy from nominal value at 1 kg is 500mg. |
| Material | Cast Iron |