Upgrade for full control of radial magnetic field errors in RFX poloidal gaps

The good results of the local feedback control of the field error at one of the poloidal gaps suggested to install a new active system at the second gap. The new power coils have been equipped with steel plates instead of copper plates as the old ones. In the paper the upgrade of the power supply system and of the digital control system are described; a comparison of the performances obtained with the two sets of coils is also reported. Finally, experimental results with plasma are presented.