Abstract: A protection adapter for the overvoltage protection of an electrical operating device in a high-voltage line. The protection adapter has a first adapter interface for electrically conductively coupling to an open-air interface of the high-voltage line, a second adapter interface for electrically conductively coupling to an operating-means interface of an electrical operating device, a connecting line for electrically conductively coupling the first adapter interface and the second adapter interface, and an electrically insulating insulation sheath which surrounds at least the connecting line. The protection adapter has a characteristic impedance for reducing electrical surges from the high-voltage line. There is also described a system with a high-voltage line, an electrical operating device, and a protection adapter.