Varistors for High Temperature and High Surge - HMOV™ Series

Littlefuse's HMOV varistor series can operate at ambient temperatures up to 125°C

Image of Littlefuse's HMOV Varistor SeriesThe HMOV varistor series from Littelfuse can operate at ambient temperatures up to 125°C with 2500 V isolation voltage, an advance made possible through the use of a new silicone coating technology. Competitive epoxy-coated varistor designs are typically limited to maximum temperatures of just 85°C while similar phenolic coating designs have limited isolation voltages. This high operating temperature makes it possible to reduce end-product production costs by eliminating the need for an additional heat sink or potting process. The combination of high operating temperature, high surge current absorption of up to 10 kA (8/20 µs), reliability confirmed by a 1000-cycle thermal shock test, and high (2500 V) isolation voltage make it the highest performance radial-leaded varistor currently on the market.

Applications include industrial automation controls, solar power inverters, security systems, fire alarm and smoke detectors, smart meters, LED lighting base transceiver station (BTS) power supplies, and harsh environment/outdoor power supplies.

Video: HMOV Series - High Operating Temperature Varistors

  • High operating temperature of 125ºC
  • High isolation voltage of 2500 V
  • Thermal shock tested from -55ºC to +125ºC, 1000 cycles
  • Meets UL 1449 and IEC 60950-1

Image of Littlefuse's HMOV Series Guide

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  • Eliminates the need for an additional heat sink or potting process used to dissipate heat
  • Ideally suited for use in higher ambient temperature applications
  • Eliminates the need for the additional insulation material
  • Minimize PCB size by reducing space required between the varistor and other components
  • Offers enhanced reliability that can extend the lifetime of the end product
  • Enables end product worldwide compliance

HMOV Series

ImageManufacturer Part NumberDescriptionMaximum AC VoltsVaristor Voltage (Min)Varistor Voltage (Max)Available QuantityView Details
VARISTOR 39V 1.5KA DISC 10MMV10H25PVARISTOR 39V 1.5KA DISC 10MM25V35.1V42.9V1332 - ImmediateView Details
VARISTOR 680V 10KA DISC 20MMV20H420PVARISTOR 680V 10KA DISC 20MM420V612V748V669 - ImmediateView Details
VARISTOR 390V 10KA DISC 20MMV20H250PVARISTOR 390V 10KA DISC 20MM250V351V429V309 - ImmediateView Details
VARISTOR 360V 3.5KA DISC 10MMV10H230PVARISTOR 360V 3.5KA DISC 10MM230V324V595V518 - ImmediateView Details
VARISTOR 390V 3.5KA DISC 10MMV10H250PVARISTOR 390V 3.5KA DISC 10MM250V351V429V640 - ImmediateView Details
VARISTOR 820V 6.5KA DISC 14MMV14H510PVARISTOR 820V 6.5KA DISC 14MM510V738V902V586 - ImmediateView Details
VARISTOR 22V 3KA DISC 14MMV14H14PVARISTOR 22V 3KA DISC 14MM14V19.8V24.2V263 - ImmediateView Details
VARISTOR 680V 6.5KA DISC 14MMV14H420PVARISTOR 680V 6.5KA DISC 14MM420V612V748V229 - ImmediateView Details
VARISTOR 360V 6.5KA DISC 14MMV14H230PVARISTOR 360V 6.5KA DISC 14MM230V324V396V616 - ImmediateView Details
VARISTOR 56V 5KA DISC 20MMV20H35PVARISTOR 56V 5KA DISC 20MM35V50.4V61.6V160 - ImmediateView Details
VARISTOR 910V 10KA DISC 20MMV20H550PVARISTOR 910V 10KA DISC 20MM550V819V1.001kV376 - ImmediateView Details
VARISTOR 430V 10KA DISC 20MMV20H275PVARISTOR 430V 10KA DISC 20MM275V387V473V0View Details
Published: 2017-01-18