.png)
IPFNA Pattern Selection
Professional Tool for Calculating Maximum Permissible Error (MPE) in Calibration.
Welcome to our specialized tool for metrology, quality, and engineering professionals. This MPE calculator is an essential solution for determining whether a set of standard weights is suitable for the calibration of a non-automatic weighing instrument (NAWI), such as a scale or balance.
Instructions:
1.- In the calculator, enter the range of the scale or balance.
2.- Select the units of the scale or balance.
3.- Select the resolution of the scale (d or e) .
4.- Press the "Calculate MPE" button
In the world of precision measurement, ensuring that an instrument operates within its specified tolerances is an essential requirement for complying with quality standards, industry standards, and regulations such as those established by the OIML (International Organization of Legal Metrology). Our calculator simplifies one of the most critical steps in this process, using OIML R-111.
What is the Maximum Permissible Error (MPE) and why is it so important?
The Maximum Permissible Error (MPE) is the maximum difference allowed, by regulation or specification, between the nominal value of a standard weight and its actual conventional mass value. In simple terms, it is the small error that a high-precision weight can be "tolerated" to have.
The key to good calibration lies in the following fundamental principle: the instrument you use to calibrate must be significantly more precise than the instrument being calibrated.
The Golden Rule in Calibration: The One-Third Condition (PTH/3)
To ensure the validity of a calibration, metrology establishes a crucial rule: the combined uncertainty of your standards (in this case, the sum of the PTHs of the weights you will use) must be at least three times better than the resolution (or minimum division) of the instrument to be calibrated.
Condition to be met: Resolution ≥ (Sum of PTHs / 3)
Our calculator automates this verification for you. Determine the optimal combination of weights to reach the maximum range of your scale and then check if this indispensable condition is met.
Interpreting the Results
Can be calibrated: Excellent! The result indicates that the uncertainty of your standard weights is low enough to perform a reliable calibration of your instrument, complying with the one-third rule.
Cannot be calibrated: This result means that the sum of the errors of your weights is too large compared to the resolution of your scale. To proceed, you would need to use a set of weights of a higher accuracy class (for example, going from F1 to E2).
Our tool gives you the confidence to perform accurate calibrations that meet the highest quality standards. Start calculating now and ensure the reliability of your measurements!
