XT-311 & XT-312 - Defender® Explosion-Proof Thermostat Explosion-Proof Thermostat

Ruffneck™ Defender® heavy-duty explosion-proof thermostats are the smallest, lightest, and most durable thermostats in their class, providing dependable, trouble-free service. They are designed for hazardous location temperature control, such as heating only, cooling only, or ventilation systems in demanding industrial applications, including oil refineries, petrochemical plants, pulp and paper mills, coal mines, grain elevators, hazardous waste storage facilities, and other hazardous locations where specific explosive gases or dusts are present.


  • Certified for use in hazardous locations
  • Smallest, lightest, and most durable thermostat in its class, providing dependable, trouble-free service.
  • Single pole, single throw or single pole, single throw for heating or cooling applications
  • Compatible with all Ruffneck™ FX5 and FX5-SD heaters


all-aluminum exterior
no breakable external plastic parts
no exposed copper or brass
corrosion-resistant; suitable for H2S environments
CFC & mercury free; environmentally safe, no leveling required
precision die-cast components
bimetal sensing element
fast-acting, reliable, unaffected by altitude
no delicate coils or bellows
temperature range of 36°F to 82°F (2°C to 28°C)
480 VAC maximum
compact and lightweight
3-year warranty; longest trouble-free warranty in the industry
UL listed and CSA C/US certified