A sensor arrangement for measuring properties of liquids and gases, including a probe, a probe holding element, the probe and the probe holding element configured to be connected to one another in a detachable manner, and a galvanically isolated interface that is formed by an inductive interface and/or a galvanically coupled interface, the galvanically isolated interface and/or the galvanically coupled interface being configured exclusively for energy transmission from the probe holding element to the probe. The sensor arrangement further includes at least one optical interface or at least one Bluetooth interface for bidirectional data transmission between the probe and the probe holding element.