This New Product Brief (NPB) is part of a video series highlighting the features, applications, and technical specs of newly-released products.

TDK EPCOS NT ThermoFuse Varistors

TDK’s EPCOS NT ThermoFuse Varistors have an integrated thermal fuse that trips if the varistor overheats—isolating the varistor and increasing the reliability of protected equipment. The 14mm NT14 and 20mm NT20 are designed to absorb 8/20µs surge currents up to 6kA and 10kA respectively, with maximum energy absorption of 220J and 480J for 2ms.

NT Thermofuse varistors are offered with two or three leads, with the third lead used to monitor the state of the integrated fuse. EPCOS NT ThermoFuse Varistors meet UL94 V-0 requirements and are designed for use in solar power inverters, household appliances, power supplies, lighting ballasts, smart meters, and many other applications.

  • Integrated fuse trips if varistor overheats
  • Disk diameter: 14mm or 20mm
  • NT14 Imax (8/20µs): 6kA, 130VRMS to 680VRMS
  • NT20 Imax (8/20µs): 10kA, 130VRMS to 750VRMS
  • Max energy absorption up to 480J (NT20, 2ms)
  • Optional third lead for monitoring fuse activation

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