The invention concerns a device for portable household appliance indicating position relative to a set position, adapted to be fixed and made integral with said appliance, characterised in that it comprises a case unit (1) with: means providing data concerning the appliance instantaneous position; means for determining the appliance instantaneous position comprising at least a closed housing (10) including an internal element (12) capable of moving freely in the housing (10), by the effect of gravity between stop positions wherein the internal element closes (12) an electric circuit triggering, via the data means, a signal representing the appliance instantaneous position. The invention also concerns a hedge trimmer equipped with a level indicating device.