Miniature FIREROD

Zesta Watlow Miniature FIREROD
Zesta Watlow Miniature FIREROD
Zesta Watlow Miniature FIREROD
Zesta Watlow Miniature FIREROD
The Watlow FIREROD® not only set the industry standard for cartridge heaters, it continues to make improvements in construction and design. Among these innovations is the 1⁄8 inch FIREROD. This miniature cartridge heater with swaged construction features high watt density, is capable of high operation temperature and provides long life in applications where it is essential to have a very small size.
Like all of Watlow’s other FIRERODs, the 1⁄8 inch contains a resistance wire closer to the sheath and compacted MgO insulation, which maximizes heat transfer.

Watlow Firerod Datasheet (EN)
Watlow: Your Heat Solutions Resource Brochure (EN)

Watlow Firerod Fiche Technique (FR)
Watlow: Vos Solutions de Chauffage Brochure (FR)
Back to Firerod Cartridge Heaters

Product Features

Miniature size
  • High performance in a small package
Low mass
  • Better heat transfer
  • Quicker response time
  • Longer life due to lower internal temperature
Swaged construction
  • Higher watt density
  • Higher temperature capability
  • Maximum heat transfer
  • Increased dielectric strength
Internal thermocouple option
  • Ideal solution for space-restricted applications
Stock availability
  • Stock heaters are available ranging in sizes from 1 1⁄4 to two inches (32 to 51 mm) in length. Check product catalog for sizes and electrical rating

Product Specifications

  • Inconel® is standard
  • 304 stainless steel is available
Maximum Application Temperature:
760°C (1400°F)
Maximum Voltage:
Maximum Wattage at 240V:
3.1 amp
Wattage Tolerances:
+10 percent, -15 percent
  • Actual diameter is 0.122 in. (3.10 mm) ± 0.002 in. (0.05 mm)
  • Minimum overall length is 0.875 in. (22.22 mm) (Minimum length may change based on lead construction, volts and watts, please consult factory.)
  • Maximum overall length is 12 in. (304.8 mm)
  • Length tolerance 3 in. (76 mm) and less ±3⁄32 in. (2.4 mm)
  • Length tolerance greater than 3 in. (76 mm) ± 3 percent
  • Solid lead wire is standard, but stranded is available
  • Lead options: Crimped-on, swaged-in
  • Lead types are: Fiberglass 250°C (482°F), High temperature fiberglass 450°C (842°F)
  • Teflon® 200°C (392°F)
  • Moisture resistant option: Teflon® seal and leads available
  • Welded end-disk is standard
  • Internal thermocouple available
  • Thermocouple embedded in the end-disc “C” location
  • Type J or K available (solid lead wire)
  • Swaged-in, fiberglass 250°C (482°F)
  • Swaged-in Teflon® 200°C (392°F)
  • For available lengths, consult factory
  • Lead protection options: Stainless steel braid crimped over lead end, stainless steel flexible hose crimped over lead end
  • Other options: Bent heaters up to 90° angle, one inch diameter mounting flange (FS flange)



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