Signal transmission device for analog current signals

Abstract

A signal transmission circuit for an analog current signal in an explosion-protected area includes a transformer with one or a plurality of primary-side coils and one or a plurality of secondary-side coils coupled in a common magnetic circuit via a transformer yoke and a control circuit configured to control the voltage across the one or the plurality of secondary-side coils to zero by providing a compensation current for flux compensation. The control variable corresponds to a measuring voltage which is one of obtained in dependence on a voltage across a measuring coil arranged in the magnetic circuit; and obtained in dependence on a voltage across one of the plurality of secondary-side coils in the magnetic circuit when it is de-energized. The analog current signal corresponds to or is dependent on the compensation current.

Dependencies are inferred from the claim text.