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Mercoid Series SA1100

Series SA1100 Diaphragm Operated Pressure Switch

Mercoid Series SA1100
Series SA1100

Visible Setpoint, Adjustable Deadband, Hermetically Sealed Snap Switch, Weatherproof and Explosion-proof

Weatherproof and Explosion-Proof in One Economical Enclosure
Extremely rugged construction assures excellent reliability in chemical, petroleum and industrial plants. New design also provides burst pressure protection to 3000 psi (206 bar). The rolling diaphragm design maintains a constant effective area to minimize friction. This results in a minimum deadband as low as 5% of full scale. Since many applications require higher deadbands, the Mercoid Series SA1100 includes a separate adjustment of this when necessary. A pump being used to control liquid level in a tank would be a typical situation where this feature would be important. Both setpoint and deadband adjustments are protected, yet clearly visible behind a clear polycarbonate window and are fully isolated from the electrical components for additional safety. A 7/16″ open-end wrench is the only tool required to change settings. Terminal blocks are provided for switch wiring connections and both internal and external ground screws are included. Standard housing is weatherproof to NEMA standards 1 through 4X and 13; explosion-proof to NEMA 7, Class I, Groups B, C & D; NEMA 9, Class II, Groups E, F & G. Optional construction adds drain to meet NEMA 3R IP54.



  • Wetted Materials:See Catalog page.
  • Temperature Limits:-30 to 180°F (-35 to 82°C) standard. ATEX compliant at Ambient Temperature -4 to 167°F (-20 to 75°C); Process Temperature -4 to 167°F (-20 to 75°C).
  • Pressure Limit:1200 psig (82.6 bar).
  • Enclosure Rating:Weatherproof and Explosion-proof. Listed with UL and CSA for Class I, Gorups B, C and D; Class II Groups E, F and G. ATEX Compliant CE 0344 Ex II 2 G EEx d IIC T6 Process Temperature ?75°C. Weatherproof UL Rated Type 4. Meets NEMA 4X.
  • Switch Type:SPDT or DPDT snap switch.
  • Electrical Rating:See Catalog page.
  • Electrical Connections:Screw terminal.
  • Conduit Connection:3/4″ female NPT.
  • Process Connection:1/4″ or 1/2″ female NPT.
  • Mounting Orientation:Within 20° of vertical.
  • Set Point Adjustment:Internal 7/16″ hex nuts.Weight:3.5 lb (1.6 kg).
  • Deadband:See Catalog page.
  • Agency Approvals:ATEX, CE, CSA, IECEx, UL.


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