For the MedAustron facility under construction in Wiener Neustadt, three electric field deflectors are developed in collaboration with CERN. A fast deflector is used in the Low Energy Beam Transfer line to chop the beam. The chopped beam is swept onto a Faraday cup for measurement purposes and to stop beam being sent towards the synchrotron. For the multi-turn injection of protons and ions, as well as for the slow extraction from the synchrotron, electrostatic septa are used. A novel design for MedAustron includes an inversed cathode/anode support and high voltage feedthroughs rated for 150 kV. The possibility for a higher voltage will significantly improve the conditioning process of the septa surfaces. This paper describes the requirements of these devices as well as the mechanical design and strategies adopted for their power supplies.