An endoscopic system (500, 600) comprising: an endoscope shaft (510, 610) having a proximal end and a distal end; an electrically active sensor system comprising a sensor (515, 615) mounted to the endoscope shaft proximate the distal end and positioned to sense at least one characteristic of an environment in which the distal end is located; a data signal transmission line (521, 621) connected to the sensor to transmit data signals between the sensor and a signal processor; an electrical power transmission line (520, 620) connected to the sensor to transmit power from a power source to the sensor; a floating ground element (525, 625) arranged to provide an electrical reference for elements of the electrically active sensor system, wherein the floating ground element comprises a conductive material surrounding the data signal transmission line and the electrical power transmission line, and an isolated power transformer (565, 665) coupled to the electrical power transmission line (520, 620) and the floating ground element (525, 625) to provide electrical power to the electrically active sensor system, characterised in that: the isolated power transformer (565, 665) is configured to convert ground-referenced power received from an earth ground-referenced power source (545, 645) into floating ground element referenced power and to output the floating ground element referenced power through the electrical power transmission line (520, 620), and in that the endoscopic system further comprises a capacitance (Ciso_5b, Ciso_6b) between the isolated power transformer (565, 665) and earth ground and wherein a total capacitance (Ctotal 5, Ctotal 6) between the electrically active sensor system and earth ground maintains current leakage from the endoscope shaft to a patient so as to not exceed a predetermined current leakage criteria, the total capacitance including said capacitance (Ciso_5b, Ciso_6b) between the isolated power transformer and earth ground. an endoscope shaft (510, 610) having a proximal end and a distal end; an electrically active sensor system comprising a sensor (515, 615) mounted to the endoscope shaft proximate the distal end and positioned to sense at least one characteristic of an environment in which the distal end is located; a data signal transmission line (521, 621) connected to the sensor to transmit data signals between the sensor and a signal processor; an electrical power transmission line (520, 620) connected to the sensor to transmit power from a power source to the sensor; a floating ground element (525, 625) arranged to provide an electrical reference for elements of the electrically active sensor system, wherein the floating ground element comprises a conductive material surrounding the data signal transmission line and the electrical power transmission line, and an isolated power transformer (565, 665) coupled to the electrical power transmission line (520, 620) and the floating ground element (525, 625) to provide electrical power to the electrically active sensor system, characterised in that: the isolated power transformer (565, 665) is configured to convert ground-referenced power received from an earth ground-referenced power source (545, 645) into floating ground element referenced power and to output the floating ground element referenced power through the electrical power transmission line (520, 620), and in that the endoscopic system further comprises a capacitance (Ciso_5b, Ciso_6b) between the isolated power transformer (565, 665) and earth ground and wherein the isolated power transformer (565, 665) is configured to convert ground-referenced power received from an earth ground-referenced power source (545, 645) into floating ground element referenced power and to output the floating ground element referenced power through the electrical power transmission line (520, 620), and in that the endoscopic system further comprises a capacitance (Ciso_5b, Ciso_6b) between the isolated power transformer (565, 665) and earth ground and wherein a total capacitance (Ctotal 5, Ctotal 6) between the electrically active sensor system and earth ground maintains current leakage from the endoscope shaft to a patient so as to not exceed a predetermined current leakage criteria, the total capacitance including said capacitance (Ciso_5b, Ciso_6b) between the isolated power transformer and earth ground.