The riser pipe section comprises a main tube 22 and auxiliary line elements 23 arranged parallel to tube 22. A measuring signal dependent on the flow of current through a driver transistor of the light-emitting diode is applicable to the first input and a network consisting of active andor passive components and at least one capacitor is connected to the second input. In one implementation, the update file is generated at a remote server system and downloaded to the client system. This allows for easier formation of the circuit pattern.