Circuit for sensing no-load condition

摘要

The circuit uses a current measuring device (5) in series with the load path of the switch (1), providing a diagnosis signal (DI), indicating whether the switch is open or closed. The diagnosis signal is fed to a diagnosis logic (8) providing a signal (DT) at its logic output which has a first value in the oscillating state or during the pauses in the clocked control signal (IN) for the load switch and a second value in the non-oscillating state or during interruption of the control signal.