System Control Electronics 107 service disconnect or just a service disconnect, is a fuse that is usually placed at or near the “middle” of the pack so that when the fuse is removed the potential or energy of the pack will also be cut in half and the HVIL circuit opened, so that the contactors will open. As men- tioned above, the MSD is typically designed as part of the HVIL so that the HV power cables are connected through the MSD ( Figures 5 and 6 ). Figure 5 Manual service disconnect. Image used courtesy of TE Connectivity. Figure 6 Manual service disconnect. Image used courtesy of Delphi Electronics.