Field device used in measuring and automation engineering, wherein said device comprises: a housing with a housing wall and with at least a housing chamber, wherein the housing chamber is at least partially surrounded by the housing wall; a measuring electronics unit, which is designed to generate at least a measuring signal representing a measured variable; a data transmission unit; an electronic operating circuit, which is arranged in a first housing chamber (10.1) and is designed to operate the data transmission unit and the measuring electronics unit, and to convert the measuring signal to at least a measured value; wherein the data transmission unit is arranged outside the first housing chamber and is designed to exchange data with the electronic operating circuit of the field device; wherein the data transmission unit and the electronic operating circuit are connected via an electrical signal cable, wherein the signal cable has multiple electric conductors, said electric conductors being designed to transmit a data signal between the data transmission unit and the electronic operating circuit, wherein a first electric conductor is designed to carry a first electric current transporting the data signal, and wherein at least a second electric conductor is designed to carry a second electric current transporting the data signal, wherein said second electric current is opposed to the first electric current, wherein the signal cable has a disconnecting device, wherein said disconnecting device is designed to galvanically separate, at least partially, a first signal cable section (20.1) on the data transmission unit side from a second signal cable section (20.2) on the operating electronics side, wherein each electric conductor has a first conductor section (20.11) on the data transmission unit side and a second galvanically isolated conductor section (20.21) on the operating electronics side, wherein the conductor sections are arranged on the disconnecting device, wherein the first conductor section (20.11) and the second conductor section (20.21) are galvanically isolated for at least one of the electric conductors, characterized in that the disconnecting device has an electromagnetically transparent plate (26.1) with a first side surface (26.21) and a second side surface (26.22) parallel to the first side surface, wherein, on the disconnecting device, the conductor sections of the first signal cable section are arranged on the first side surface and wherein the conductor sections of the second signal cable section are arranged on the second side surface, wherein each first conductor section is opposite the corresponding second conductor section in relation to a side surface normal, wherein the plate has at least a minimum thickness or a dielectric strength required by a safety standard. a housing with a housing wall and with at least a housing chamber, wherein the housing chamber is at least partially surrounded by the housing wall; a measuring electronics unit, which is designed to generate at least a measuring signal representing a measured variable; a data transmission unit; an electronic operating circuit, which is arranged in a first housing chamber (10.1) and is designed to operate the data transmission unit and the measuring electronics unit, and to convert the measuring signal to at least a measured value; wherein the data transmission unit is arranged outside the first housing chamber and is designed to exchange data with the electronic operating circuit of the field device; wherein the data transmission unit and the electronic operating circuit are connected via an electrical signal cable, wherein the signal cable has multiple electric conductors, said electric conductors being designed to transmit a data signal between the data transmission unit and the electronic operating circuit, wherein a first electric conductor is designed to carry a first electric current transporting the data signal, and wherein at least a second electric conductor is designed to carry a second electric current transporting the data signal, wherein said second electric current is opposed to the first electric current, wherein the signal cable has a disconnecting device, wherein said disconnecting device is designed to galvanically separate, at least partially, a first signal cable section (20.1) on the data transmission unit side from a second signal cable section (20.2) on the operating electronics side, wherein each electric conductor has a first conductor section (20.11) on the data transmission unit side and a second galvanically isolated conductor section (20.21) on the operating electronics side, wherein the conductor sections are arranged on the disconnecting device, wherein the first conductor section (20.11) and the second conductor section (20.21) are galvanically isolated for at least one of the electric conductors, characterized in that the disconnecting device has an electromagnetically transparent plate (26.1) with a first side surface (26.21) and a second side surface (26.22) parallel to the first side surface, wherein, on the disconnecting device, the conductor sections of the first signal cable section are arranged on the first side surface and wherein the conductor sections of the second signal cable section are arranged on the second side surface, wherein each first conductor section is opposite the corresponding second conductor section in relation to a side surface normal, wherein the plate has at least a minimum thickness or a dielectric strength required by a safety standard.