Apparatus for safely disconnecting an electrical load from an electrical DC voltage supply

摘要

An apparatus for disconnecting an electrical load from an input DC voltage includes first and second lines which carry the input DC voltage to the electrical load. A fuse is connected in series in the first line. The switching contact of a first relay is connected in series in the first line and is opened for a disconnection process. The switching contact of a second relay is connected in parallel between the first and the second line downstream of the first relay and, when a disconnection process takes place, is closed once the first relay has been opened. The apparatus has a high availability despite the use of commercially available relays.