This episode of Tech Specs is part of a video series highlighting the features, applications, and technical specs of newly-released products.

TDK & EPCOS ThermoFuse Varistors

EPCOS NT series ThermoFuse varistors are disk varistors with a thermally coupled fuse. If the thermistor overheats, the fuse trips and prevents the varistor from turning into a fireball and charring the rest of your design. The NT14 and NT20 are 14 and 20-millimeter diameter disks that can be used in existing footprints, adding an extra layer of safety to your design. These varistors also offer voltage ratings up to 750 volts RMS, and surge current capability up to 10,000 amps, with a maximum energy absorption of 480 joules for 2 milliseconds. In addition to the thermal resistance—they have a flame-retardant epoxy coating, meet UL 94 V-0 requirements, and are UL 1449 Type 4CA listed components.

  • Thermal fuse protected varistor
  • Compact size: 14 mm (NT14) and 20 mm (NT20) disk diameter
  • Operating voltages: 130 VRMS to 750 VRMS
  • Surge current capability: up to 10 kA
  • Energy absorption: up to 480 J for 2 ms
  • UL 1449 Type 4CA listed

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