Dwyer Series 43000 Capsu-Photohelic® Pressure Switch/Gage

 Dwyer Company Headquarters is in Michigan City, Indiana. Dwyer uses advances computer modeling software to simulate real world situations, creating more accurate measurement techniques in our products. Innovative product designs have been recognized by industry experts, including ACHR Dealer Design Awards in the Testing and Monitoring category for 2014 and 2015.

Dwyer Series 43000 Capsu-Photohelic® Pressure Switch/Gage

Dwyer has invested in state of the art research and development facilities for best in class product testing and verification. Dwyer has a long history of innovation in designing and manufacturing our own measurement sensors that provide superior product performance.

Series 43000 Capsu-Photohelic® Pressure Switch/Gage

Known for quality, reliability and accuracy, Dwyer designs and manufactures a full-line of Controllers, Data Loggers, Gages, Manometers, Monitors, Remote Displays, Switches, Transmitters, and Accessories to measure, monitor and control pressure, air velocity, flow, fan pressure, duct, and more.

Dwyer’s wide selection extends to Gages, Transmitters, Switches, Data Loggers, and Monitors for Differential Pressure. Dwyer manufactures a range of dial and digital gages to reliably measure and display pressure difference, between two pressure sources using gas or liquid in a process flow.

Dial Gages and Switches are compatible with air and other non-combustible and non-corrosive gases. Dial Gages and Dial Switches are indicators for the difference between two pressures that also have switch outputs. They can also be used for single pressure.

Series 43000 Capsu-Photohelic® Pressure Switch/Gages function as versatile, highly repeatable pressure switches combined with a precise pressure gage employing the time-proven Magnehelic® gage design. The Capsu-Photohelic® switch/gage employs an encapsulated sensing element for use with both liquids and gases at pressures to 500 psig (34 bar). Optional cast brass case is available for water or water based liquids. Two phototransistors actuated, DPDT relays are included for low/high limit control. Easy to adjust set point indicators are controlled by knobs located on the gage face. Individual set point dead-band is one pointer width — less than 1% of full scale. Set points can be interlocked to provide variable dead-band — ideal for control of pumps.


  • Gage capsule permits high-pressure usage with small differentials
  • Zero and range adjustments outside of gage means no disassembly in normal service
  • Time-proven, simple, frictionless movement that permits full scale readings as low as 0.5 in w.c.
  • Photo-electronic relays provide fast-acting switching with variable deadband control for chatter-free operation


  • Pump control
  • Pumping systems
  • Waste water
  • Compatible liquid or gas applications

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Gage Specifications 
ServiceCompatible gases and liquids. Brass case option required for water based liquids.
Wetted MaterialsConsult factory.
Accuracy±3% of FS at 70°F (21.1°C). ±4% on 43215, 43220 and 43500.
Pressure Limits-20 Hg to 500 psig (-0.677 to 34.5 bar).
Temperature Limits20 to 120°F (-6.67 to 48.9°C). Low temperature option available.
Process Connections1/4" female NPT.
Size4" (101.6 mm) dial face, 5" (127 mm) OD x 9-3/16" (233.36 mm).
Weight5 lb. 8 oz (2.49 kg). Brass 11 lb. 2 oz (5.05 kg).
Switch Specifications 
Switch TypeEach setpoint has 2 form C relays (DPDT).
Repeatability±1% of FS.
Electrical Rating10 A @ 120 VAC, 6 A @ 240 VAC, 60 Hz res. 10 A @ 28 VDC.
Electrical ConnectionsScrew terminals.
Power Requirements120 VAC, 50/60 Hz; 240 VAC & 24 VAC power optional.
Mounting OrientationDiaphragm in vertical position. Consult factory for other position orientations.
Set Point AdjustmentAdjustable knobs on face.

Download Data Sheet: Series 43000 Capsu-Photohelic® Pressure Switch/Gage

Ref: dwyer-inst.com