An electric field in the RID is produced by grounding the odd panels (the central and the two side panels) and by applying negative voltage (−20±5 kV at 50 Hz with trapezoidal wave form) to the two even walls named middle panels in order to deflect the residual ions.4 So, the neutralization requirement determines the geometrical configuration of neutralizer and RID panels with the beam focus positioned at the beam exit section of the RID for each beam channel and at the tokamak porthole for all the beam channels.