Siemens HF365NA Fusible Safety Switch 3P4W 400A 600V

Siemens HF365NA is a Heavy Duty Safety Switch (HDSS) that serves as a fusible disconnect for 600 V systems. This 3-pole, 4-wire (3P4W) unit is rated for 400 A and ships with 400 A fuses installed. It is designed for indoor use in a NEMA 1 enclosure (N1 series A), making it suitable as a service-entrance disconnect or motor feeder in industrial and commercial power distributions. The 600 V rating supports three-phase applications with a neutral conductor where required, and the 3P4W configuration ensures proper control of three-phase loads with a return path. This HF365NA model is part of Siemens’ VBII family of heavy-duty safety switches, providing a robust isolation point for maintenance and system protection in electrical distribution panels and industrial equipment enclosures.