Sepam T Series

About this product

The Schneider Electric Sepam T Series provides dedicated MV transformer protection for the full range of power transformer applications from small distribution transformers to large unit transformers requiring differential protection. The series addresses transformer protection at five function levels: T20 for basic overcurrent and earth fault protection on small distribution transformers; T23 adding breaker failure protection (50BF); T40 adding directional protection, voltage and frequency monitoring and 8 RTD inputs for oil and winding temperature monitoring; T42 adding directional earth fault (67N) for transformers in isolated or compensated neutral networks; and T87 providing full biased transformer differential (87T) with restricted earth fault (87N) for large power transformers. Buchholz relay and thermistor inputs are standard on all T-series models, providing the gas detection and oil temperature protection functions essential for oil-filled power transformers. The protection characteristic settings including differential bias slope, harmonic restraint for magnetising inrush blocking and vector group compensation are configurable via the Sepam S1 software or the optional graphical UMI display. RS485 communication with IEC 60870-5-103 or Modbus RTU enables direct SCADA integration. Typical applications include MV/LV distribution transformer protection in utility secondary and primary substations, industrial MV transformer protection in process facilities and manufacturing plants, and large power transformer protection in generating stations and transmission substations where T87 differential protection provides the early internal fault detection that is critical for limiting transformer damage and replacement cost.

Technical Specifications

Ordering Options