Fast particle driven instabilities are investigated at low toroidal field in Tritium (T), Deuterium (D) and Hydrogen (H) plasmas. T, D, H neutral beams with energies of 160keV, 140keV and 110keV were injected respectively into T, D and H plasmas. The destabilisation of Alfvén Eigenmodes (AE) was observed during injection of tritium beams into a tritium plasma and during the injection of deuterium beams into a deuterium plasma but not during the injection of hydrogen beams into a hydrogen plasma