High-grade stainless steel knob and wire reference weights in class "E0" - with a higher accuracy than OIML class E1 weights - enable calibration of mass standards with the highest metrological performance.
To produce “E0” weights, METTLER TOLEDO hand-selects the best E1 weights which are then calibrated by an NMI with an uncertainty of 1/5*MPE (E1). These reference weights are delivered with an NMI calibration certificate.
Microgram weights and weight sets (50 µg to 500 µg) are used predominantly for scientific research and calibration. They also support general industrial research in areas where instrument calibration with milligram weights is not sufficiently accurate. Read more
Handling microgram weights can be a challenge. A specially developed set of tools makes routine use easy and ensures safe and proper handling. It is a simple matter to lift the weights from the magazine and place them on a robotic or manual balance.
A fully developed system with unique, specially designed tools simplifies the whole measuring process and sets a complete new standard for smart handling. This system includes a special handling tool, an acclimatization magazine, a protective aluminum container, and ceramic tweezers.
It is commonly called an E0 class, but in reality it is an E1 weight with a lower uncertainty and a maximum permissible error of 1/5, compared to a standard E1 weight.
No, the calibration of an E0 weight is performed at a national metrology institute, either PTB in Germany or METAS in Switzerland.
Reference weights are used by national metrology institutes to calibrate other weights (for example of their customers).