A welding power source comprising: - a housing formed from a metallic material, - a welding inverter, - a digital, electronic welding process computing unit, and - a human-machine interface device, wherein the welding process computing unit is configured so as to drive the welding inverter, wherein the welding process computing unit and the welding inverter are arranged in the housing and the human-machine interface device is fixed to the welding power source outside the housing, wherein the welding power source additionally comprises a digital, electronic human-machine computing unit externally fixed to the welding power source outside of the housing, and wherein the human-machine interface device is connected to the human-machine computing unit, and wherein the human-machine computing unit and the welding process computing unit are networked to one another via a communication link and form a computer network, [wherein] the welding power source is characterized in that the human-machine computing unit and the welding process computing unit are galvanically separated from one another by means of one or more optocoupler(s) or inductive coupler(s), and the communication link is a field bus connection. - a housing formed from a metallic material, - a welding inverter, - a digital, electronic welding process computing unit, and - a human-machine interface device, wherein the welding process computing unit is configured so as to drive the welding inverter, wherein the welding process computing unit and the welding inverter are arranged in the housing and the human-machine interface device is fixed to the welding power source outside the housing, wherein the welding power source additionally comprises a digital, electronic human-machine computing unit externally fixed to the welding power source outside of the housing, and wherein the human-machine interface device is connected to the human-machine computing unit, and wherein the human-machine computing unit and the welding process computing unit are networked to one another via a communication link and form a computer network, [wherein] the welding power source is characterized in that the human-machine computing unit and the welding process computing unit are galvanically separated from one another by means of one or more optocoupler(s) or inductive coupler(s), and the communication link is a field bus connection. wherein the welding process computing unit is configured so as to drive the welding inverter, wherein the welding process computing unit and the welding inverter are arranged in the housing and the human-machine interface device is fixed to the welding power source outside the housing, wherein the welding power source additionally comprises a digital, electronic human-machine computing unit externally fixed to the welding power source outside of the housing, and wherein the human-machine interface device is connected to the human-machine computing unit, and wherein the human-machine computing unit and the welding process computing unit are networked to one another via a communication link and form a computer network, [wherein] the welding power source is characterized in that the human-machine computing unit and the welding process computing unit are galvanically separated from one another by means of one or more optocoupler(s) or inductive coupler(s), and the communication link is a field bus connection.