In a method for extinguishing an arc in a gas discharge chamber in which power is supplied to a gas discharge chamber and in which both with a current flow in a first direction and with a current flow in a second inverse direction there is produced a gas discharge, when an arc is identified, the power supply to the gas discharge chamber is interrupted, and residual energy which is in a supply line to the gas discharge chamber and/or in the gas discharge chamber is supplied to an energy store.