Schneider Electric 55GFMSJD450E Circuit Breaker

55GFMSJD450E is a Bussmann Series high‑voltage fuse (Eaton Bussmann) rated for 450 A at 5.5 kV, designed for use in Square D HVL/cc switchgear as a single‑barrel protective device. The catalog suffix encodes the amperage, with 450E indicating a 450‑ampere rating, while the 55G family identifies the 5.5 kV class fuse. This part is specified for use with 600 A Square D HVL/cc switches in utility substations and transmission/distribution installations. The unit is approximately 28.82 inches long and configured as a single‑barrel cartridge to fit HVL/cc switchgear footprints. Typical deployments protect high‑voltage feeders and switchgear assemblies operating around 5.5 kV within the Square D HVL/cc ecosystem. As a dedicated protective device within HVAC/cc distribution schemes, it supports coordinated backup and fault protection in utility infrastructure where fast isolation of faults on high‑voltage circuits is required.