Schneider Electric S33579 Current Transformer

Schneider Electric S33579 is an external current sensor (CT) designed as a spare part for MasterPact MTZ1/MTZ2/MTZ3 circuit breakers, identified in catalogs as LV833579SP. It provides current monitoring for the MDGF SGR and earth‑fault protection functions, enabling reliable ground‑fault detection in high‑current installations. The unit is specified for a 300 A–800 A primary current rating, making it suitable for MTZ assemblies configured to monitor large conductor currents. As an external sensor, the S33579/LV833579SP integrates with the MasterPact MTZ protection architecture, delivering accurate current data to the control unit to support MDGF/SGR protection decisions. This sensor is intended for replacement within MasterPact MTZ systems to restore protection in industrial and commercial power distributions that rely on robust earth‑fault and source‑ground‑return protection.