In our previous blog, we discussed the difference between E1 and E2 class weights. Now, let’s dive into the key differences between F1 and F2 accuracy class weights. Both of these weight classes are quite similar in terms of design, shape, and materials used for construction, but there’s one crucial distinction: the maximum permissible error.

What’s the Difference Between F1 and F2 Weights?

The main difference between F1 and F2 class weights lies in their accuracy. The F1 class weights have a lower permissible error compared to the F2 class weights. To put it into perspective:

• For a 1 mg weight, the maximum permissible error for F1 class weights is 0.020 mg.
• For the same 1 mg weight, the maximum permissible error for F2 class weights is 0.060 mg.

This means that F1 class weights are about three times more accurate than F2 class weights. This makes F1 class weights a better choice for applications where higher precision is crucial.

Which Accuracy Class Should You Choose?

The choice between F1 and F2 class weights depends largely on the accuracy requirements of your weighing balance and the nature of your application.

• Weighing Balances with Higher Accuracy (e.g., 1mg Readability):

If you are working with a weighing balance that has a maximum capacity of 200g and a readability of 1mg, F1 class weights are ideal. The higher accuracy of F1 ensures that the balance remains precise and accurate, with minimal error.

• Weighing Balances with Lower Readability (e.g., 10mg Readability):

On the other hand, if your balance has a readability of 10mg, F2 class weights may be more suitable. These weights are perfectly fine for balances where the required precision is lower.

General Selection Criteria

A good rule of thumb when choosing between F1 and F2 weights is that the error or uncertainty of the weights should be three times better than the error of the weighing balance itself. This ensures that the weights’ accuracy exceeds that of the balance and doesn’t introduce unnecessary errors into the calibration process.

Standard Operating Procedures (SOP) and Weight Selection

Another important factor in selecting the right weight class is the Standard Operating Procedure (SOP) of your organization or lab. The SOP typically defines the desired accuracy for the process. For example, if the SOP states that the desired accuracy is 0.1%, you should select a weight class that meets this requirement.

If the SOP specifies a higher accuracy, then you should opt for F1 class weights. If lower accuracy is acceptable, F2 class weights may be the better choice.

Where to Find More Information?

If you need more detailed information on the maximum permissible errors for F1 and F2 class weights, you can refer to OIML R-111 standards. Alternatively, you can reach out to a Masse Präzise representative for specific guidance.

In summary, choosing between F1 and F2 class weights ultimately depends on the accuracy requirements of your weighing balance and application. For high-precision needs, F1 class weights are the preferred choice, while F2 class weights are suitable for less demanding applications. Always refer to the guidelines of your SOP and ensure that the weight’s accuracy aligns with the desired performance of your balance.

By understanding these differences and following the right selection criteria, you can ensure the most accurate calibration for your instruments.