The subject matter herein generally relates to electrical generators and motors, and more specifically, to electrical turbo-generators. In an embodiment, an electrical system includes a circuit. The circuit includes one or more rotating power delivery assemblies comprising a plurality of sliding surfaces that deliver power to a rotating load. The circuit also includes one or more radio frequency current transformers (RFCTs) that measure radio frequency (RF) signals corresponding to arcing events in the one or more rotating power delivery assemblies. The electrical system also includes a processor that receives the measurements from the one or more RFCTs and determines a health value of the circuit based, at least in part, on the received measurements.