Kev:

If you are using a FADEC ECU which is what as far as I know WREN uses, you should be OK with the ni-cad, I really do not know the reason for the suggestion from wren not to use them, did you e-mail them? did you allow the turbine to continue the sequence to see if it will reach idle? did it? I can tell you I have seen that kind of behaviour whenever there happens the second step on the ramping stage and the starter has disengaged. What is your starter switch off RPM set at?(parameter 23 on a FADEC). Did you check that the pump is working? another reason could be that your are still running on gas only