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Duotect Series H2

Series H2 Dual-Action Explosion-proof Pressure Switch

Duotect Series H2
Duotect Series H2

Explosion-proof and Weatherproof Housing

Explosion-proof, UL & CSA Listed for Class I, Groups B, C & D and Class II, Groups E, F & G. The Duotect Series H2 is designed for sequencing two different actions as pressure of a liquid or gas increases or decreases. The design consists of two concentric pistons operated by a single diaphragm with one pressure chamber. Each piston actuates a separate switch independent of the other. The switches may be adjusted to operate together, at opposite ends of the range or at two intermediate set points. The threaded top is removed to field adjust or service switches without disturbing electrical or pressure connections. The Duotect® switch is explosion-proof and weatherproof. It can be mounted in any position and is not affected by vibration.



  • Wetted Materials:316 SS chamber with FEP diaphragm and Buna-N O-ring standard. Fluoroelastomer or EPDM O-ring optional.
  • Temperature Limit:275°F (135°C). CSA approved: -20 to 90°C (-4 to 184°F).
  • Pressure Limit:1500 psig (103 bar).
  • Enclosure Rating:UL listed explosion-proof, Class I, Groups B, C, and D. Class II Groups E, F, and G. Meets NEMA 4X (IP66). CSA optional. Class I, Groups B, C & D. Class II, Groups E, F, & G -20°C ≤ Tamb ≤ 75°C T6 [optional -20°C ≤ Tamb ≤ 40°C T5] Type 4.
  • Switch Type:Two SPDT snap switches.
  • Electrical Rating:5 A @ 125/250 VAC, 5 A res., 3 A ind. @ 30 VDC. Gold contacts or 10 A switch optional.
  • Electrical Connections:18 AWG, 18″ (460 mm) long.
  • Conduit Connection:3/4″ female NPT.
  • Process Connection:1/4″ female NPT.
  • Mounting Orientation:Any position.
  • Set Point Adjustment:Internal nut.Weight:2 lb (.9 kg).
  • Deadband: Approximately 10% of range.
  • Agency Approvals: CSA, UL.


Popular Models

H2S-1Duotect® dual-action explosion-proof pressure switch, 3-40 psig (0.21-2.76 bar) low range, 5-75 psig (0.35-5.17 bar) high range
H2S-2Duotect® dual-action explosion-proof pressure switch, 25-250 psig (1.72-17.2 bar) low range, 30-400 psig (2.07-27.6 bar) high range
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