The construction of the new Joule balance at the NIM

The Joule balance method is one of the several approaches to measure the Planck constant for the redefinition kilogram. The first prototype has been built to check the feasibility of the principle and the relative uncertainty is 2.6×10
⁻⁶
. To get better result and make contribution for the redefinition, since 2013, a new Joule balance has been designed with several new approaches to decrease the main uncertainty contributions in the first prototype. In 2015, the new joule balance has been mounted and some rough measurements have been done in air for the fine adjustment and alignment in the near future.