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Related Item: Duotect Series H3 Pressure Switches

Duotect Model H2 Dual Action Explosion Proof Switches

Explosion Proof & Water Proof Housing

Explosion-proof, UL & CSA Listed for Class I, Groups B, C & D and Class II, Groups E, F & G. The H2 is designed for sequencing two different actions as pressure of a liquid or gas increases or decreases. The patented 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. Dimensional Information


  • 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: CE, CSA, UL.
MODELS NUMBERS (stock shown in bold)
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