The WISArD experiment is probing the possible existence of exotic currents in the electroweak sector using nuclear β decay, to improve the constraints on beyond Standard Model physics. The setup of the experiment underwent a full upgrade between 2018 and 2021 in preparation of a second run of data taking at ISOLDE, CERN, scheduled for October 2021. The detector stage was completely renewed to improve statistics and minimize the main systematic effects identified in a proof-of-principle run in 2018. With this upgrade, the objective is to reach the per-mil level of uncertainty on the angular correlation coefficent a and on the Fierz interference term b, in a pure Fermi transition. In this case, both parameters are directly sensitive to the possible contribution of exotic scalar currents.
