Final report on force key comparison EUROMET.M.F-K2: 50 kN and 100 kN (EURAMET Project No 518)

This report describes EURAMET Key Comparison EUROMET.M.F-K2, a comparison between the force standard machines of twelve national measurement institutes, at generated forces of 50 kN and 100 kN, in the period from 2007 to 2009. Two different measurement schemes were employed, one for machines capable of generating both 50 kN and 100 kN and the other using the single force of 50 kN, for machines of a lower maximum capacity than 100 kN. Multiple transducers were used and the force-time profile was strictly controlled, to minimise effects of creep. Analysis of the results took careful account of the drift of the transducers' sensitivities throughout the comparison period, as this was one of the major uncertainty contributions. The final results are linked to the KCRV determined in CIPM Key Comparison CCM.F-K2 through the use of two common deadweight force standard machines in the two comparison exercises.