A sensor system comprising: an exchangeable cartridge (CR, 110, 210) with an examination region in which a sample can be provided and with a first and a second contact region (C1, C2, C3) where it can be contacted; a reader (RD, 150) with an accommodation space for the cartridge (CR, 110,210) and with a sensor unit (155, 156) for making measurements in the examination region of the cartridge (CR, 110, 210); at least one contact element (CE, 111, 211) by which the cartridge (CR, 110, 210) is supported in the accommodation space and which comprises or touches the first contact region (C1, C2), wherein there exists a "high-resistance" cross section (a-a) through the contact element (CE, 111, 211) for which the thermal resistance is higher than the thermal resistance at any other "low-resistance" cross section (b-b) that (i) cuts through the body of the cartridge (CR, 110, 210), (ii) comprises the examination region, and (iii) separates the first contact region (C1, C2) from the second contact region, characterized in that the contact element (CE, 111, 211) comprises a leg (111, 211) extending from the cartridge (CR, 110, 210) or the reader, wherein the leg (111, 211) comprises a rounded tip with a radius l of curvature between 10 μm and 1000 μm, wherein the leg (111, 211) comprises a zone of lower thermal conductivity achieved by the inclusion of a thermally insulating material, and wherein said high-resistance cross section (a-a) passes through said zone. an exchangeable cartridge (CR, 110, 210) with an examination region in which a sample can be provided and with a first and a second contact region (C1, C2, C3) where it can be contacted; a reader (RD, 150) with an accommodation space for the cartridge (CR, 110,210) and with a sensor unit (155, 156) for making measurements in the examination region of the cartridge (CR, 110, 210); at least one contact element (CE, 111, 211) by which the cartridge (CR, 110, 210) is supported in the accommodation space and which comprises or touches the first contact region (C1, C2), wherein there exists a "high-resistance" cross section (a-a) through the contact element (CE, 111, 211) for which the thermal resistance is higher than the thermal resistance at any other "low-resistance" cross section (b-b) that (i) cuts through the body of the cartridge (CR, 110, 210), (ii) comprises the examination region, and (iii) separates the first contact region (C1, C2) from the second contact region, characterized in that the contact element (CE, 111, 211) comprises a leg (111, 211) extending from the cartridge (CR, 110, 210) or the reader, wherein the leg (111, 211) comprises a rounded tip with a radius l of curvature between 10 μm and 1000 μm, wherein the leg (111, 211) comprises a zone of lower thermal conductivity achieved by the inclusion of a thermally insulating material, and (i) cuts through the body of the cartridge (CR, 110, 210), (ii) comprises the examination region, and (iii) separates the first contact region (C1, C2) from the second contact region, characterized in that the contact element (CE, 111, 211) comprises a leg (111, 211) extending from the cartridge (CR, 110, 210) or the reader, wherein the leg (111, 211) comprises a rounded tip with a radius l of curvature between 10 μm and 1000 μm, wherein the leg (111, 211) comprises a zone of lower thermal conductivity achieved by the inclusion of a thermally insulating material, and characterized in that the contact element (CE, 111, 211) comprises a leg (111, 211) extending from the cartridge (CR, 110, 210) or the reader, wherein the leg (111, 211) comprises a rounded tip with a radius l of curvature between 10 μm and 1000 μm, wherein the leg (111, 211) comprises a zone of lower thermal conductivity achieved by the inclusion of a thermally insulating material, and wherein said high-resistance cross section (a-a) passes through said zone.