The electronics of the device are bus powered. Therefore, a grid voltage failure only leads to a functional failure of the device if the bus voltage also fails as a result of the grid voltage failure.

In the event of bus voltage failure, the current status and other values for each input are permanently saved so that they can be restored when the bus voltage is recovered.

When bus voltage is recovered, the configured actions for each input are configured and, depending on the parameters set, new statuses are reported.