E1 & E2 Test weights

Mass-standard and normal weights: Weights of OIML accuracy class E1

Weights to ensure traceability between the national mass standards (whose values are derived from the International Prototype of the Kilogram) and the weights of class E2 and lower. read on ...

Standard masses and standard weights

Weights of OIML accuracy class E1 Weights of OIML accuracy class E2
E1 Calibration weights suitable for applications with the highest security requirements and customers with the most stringent demands. The E1 standard masses are used for the calibration and verification of high-resolution balances with a division d > 1,000,000. Weights for the calibration of F1 class weights or weights used with accuracy class I balances.
E2 Calibration weights suitable for applications with high security needs and customers with the highest demands. The E2 standard masses are used for the calibration and verification of high-resolution analytical balances of verification class I with a division d ≥ 1,000,000.

A calibration certificate must always be issued for weights of class E!

The following values are mandatory on the calibration certificate for weights of class E1:

  • Conventional weight value, mc
  • Expanded uncertainty, U
  • Expansion factor, k
  • Density or volume of each weight with specification of whether density or volume has been measured or estimated.

The following values are mandatory on the calibration certificate for weights of class E2:

  • Conventional weight value, mc
  • Expanded uncertainty, U
  • Expansion factor, k
  Reference density 8.0 g/cm3

Adjustment chamber - Weights of class E from 1 mg to 50 kg are solid and have no open voids to the atmosphere. As monoblock weights, they are made from a single piece without an adjustment chamber. Weights of class E2 over 50 kg may have a correction chamber.

Surface - The polished, mirror-smooth surface provides an anti-adhesion effect.

They can be used as weights of class E1 if they meet the requirements regarding surface roughness, magnetic susceptibility, and magnetization for weights of class E1, and these data are specified in the calibration certificate.