An implantable electrode arrangement for an ear implant system is described. A proximal electrode lead has electrode wires for carrying one or more electrical stimulation signals. A distal electrode array has electrode contacts each forming a terminal end of an electrode wire for applying the electrical stimulation signals to target neural tissue, and one or more intra-operative sensors for generating insertion sensing signals during surgical insertion of the electrode array into the target tissue. An intra-operative electrode section has a sensor connector for providing a temporary connection of one or more external measurement arrangements to the one or more intra-operative sensors during the surgical insertion of the electrode array without being functional after the surgical insertion.