A switch assembly is disclosed for use in a circuit configured to carry a current between a first electrical conductor and a second electrical conductor. The switch assembly includes at least a first current path and a second current path, each of which includes an electrical contact which can be selectively connected to or disconnected from the second electrical conductor. At least one of the first current path and the second current path is configured such that it has a frequency-dependent reactance or impedance so as to force or cause current with a frequency which complies with a selected frequency criterion and which flows between the first electrical conductor and the second electrical conductor to flow, at least to a greater extent, via a selected one of the first current path and the second current path.