Abstract: A method of earthing two current inlet/outlet systems in a medium or high voltage switchgear using one circuit breaker comprises the following steps: a) switching OFF the circuit breaker; b) connecting the circuit breaker to the first current inlet/outlet system as well as to the earthing; c) switching the circuit breaker ON; d) providing a direct connection between the first current inlet/outlet system and the earthing via a connecting element; e) switching the circuit breaker OFF; f) disconnecting the circuit breaker at least from the first current inlet/outlet system; g) connecting the circuit breaker to the second current inlet/outlet system and to the earthing; and h) switching the circuit breaker ON. A switchgear apparatus to be used for said method is described as well.