Diaphragm Type Gauge – Gases & Liquids

0-20” H2O to 0-100 PSID

  • Safe working Pressures up to 3,000 PSI
  • Rugged construction Weather Proof design
  • Common Applications:
    • Filter and Strainer Monitoring
    • Compressed Air
    • Hydraulic
    • Refrigerant
    • Pump Performance Testing
    • Heat Exchanger Pressure Drop Monitoring
    • Valves, Chillers etc,, and for local flow indication and control
  • Gauge, Switch and Transmitter options

Diaphragm Gauge Description:

Mid-West® Instrument Diaphragm ΔP Gauges- Our diaphragm type gauge,  the high and low-pressure ports are completely isolated from each other. There is no bypass and therefore they can be used for air, gas and liquids. They also come in a variety of dial scales allowing for very sensitive measurements. The Differential Pressure is sensed by the movement of an elastomer diaphragm against a precision calibrated range spring. The change in position of the diaphragm in response to the change in Differential Pressure moves an internal magnet. This magnet, in turn, causes a rotary magnet external to the gauge body to rotate and indicate ΔP on a dial.

Diaphragm-Type Differential Pressure Gauges are available with one or two hermetically sealed reed switches or a 4-20mA transmitter model dependent. The switches are adjustable within a defined percentage of the full scale range of the gauge and are available in SPDT and SPST normally open configurations for various load/power ratings. The switches can be set to activate or deactivate on rising or falling pressure. Models 130, 140, 142, 522, & 522A Switches are “CE” marked per the EU Low Voltage and RoHS Directives.

The Model 700 series uses a piezoresistive differential pressure sensor element.  Silicone oil is filled between the die and 2 stainless steel diaphragms. The measured differential is amplified into a usable voltage or converted into a 4-20 ma output.

Hazardous location switches Models 140, and 142 are certified CSA and UL to Canadian & US Standards. Model 240 is CSA, UL Listed and CE marked to the ATEX directive and KOSHA certified along with the option for DPDT relays for higher load applications. The CSA & UL listings are for the entire assembly and not just the enclosure. See individual models for complete specifications.


OEM, Private Label, Special Dials:

Mid-West Instrument has the capability to design and engineer a Differential Pressure Gauge, Switch or Transmitter to the exact requirements of the customer. Dial size, Process connection Size and location, etc. can also be customized to the customer’s requirements. Mid-West has one of  the fastest production times in the Industry. Our standard production time on most gauges is 7-10 business days or less.

Mid-West Instrument has the equipment and printing technology to provide color dials, flow scales and customer logo dials.

Please contact your Sales Coordinator for additional information and terms.

“Diaphragm Type” Gauges with Electrical Optional

Model No. Differential Pressure Range Accuracy Working Pressure Electrical Available Specifications Installation/ Operation Manual Electrical IOM Drawing
Model 114 0-0.72 PSID (0-20" H20) to 0-20 PSID (0-600" H2O)
Tank Level Applications
±2% 1000 PSI CE / LVD, RoHS Compliant, NEMA 4X, 4-20mA Transmitter
Model 130 0-5" H2O to 0-15 PSID (0-400" H2O) 0-5" H2O to 0-9.9" H2O
±5%
0-10" H2O to 0-15 PSID
±3/2/3%
Up to 500 PSI CE / LVD, RoHS Compliant, NEMA 4X, Class 1-Div. 1
Model 140 0-50" H2O to 0-100 PSID 0-50" H2O to 0-399" H2O
±5%
0-15 PSID to 0-100 PSID
±3/2/3%
Up to 3,000 PSI CE / LVD, RoHS Compliant, NEMA 4X, Terminal Strip, Class 1-Div. 1, Class 1-Div. 2, 4-20mA Transmitter N/A
Model 142 0-20" H2O to 0-25 PSID ±3/2/3% Up to 3,000 PSI CE / LVD, RoHS Compliant, NEMA 4X, Terminal Strip, Class 1-Div. 2, 4-20mA Transmitter
Model 522 0-5 PSID to 0-50 PSID ±5% 1,000 PSI CE / LVD, RoHS Compliant N/A

Electrical “Diaphragm Type” Gauges

Model No. Differential Pressure Range Accuracy Working Pressure Electrical Available Specifications Installation/ Operation Manual Electrical IOM Drawing
Model 240 0-20" H2O to 0-100 PSID ±3/2/3% Up to 1500 PSI CE / ATEX / RoHS Compliant CSA, UL & KOSHA CERTIFIED, NEMA 4X, Terminal Strip, Class 1-Div. 1, Class 1-Div. 2, 4-20mA Transmitter N/A
Model 700 / 710 / 715 0-5 PSID to 0-300 PSID ±0.50% 2,900 PSI 2-Wire
4-20 mA Transmitter 15-28 VDC, LCD = 4-20 mA Transmitter 18-28 VDC, LED = 4-20 mA Transmitter 20-28 VDC
3 Wire
15-28 VDC/1-5 VDC, 15-28 VDC/0-5 VDC, 15-28 VDC/0-10 mADC, 15-28 VDC/0-20 mADC, 15-28 VDC/0-10 VDC
N/A

“Indicator”  Style Diaphragm Type Gauges

Model No. Differential Pressure Range Accuracy Working Pressure Electrical Available Specifications Installation/ Operation Manual Electrical IOM Drawing
Model 522C3-Color Dial 0-5 PSID to 0-50 PSID ±5% 1,000 PSI CE / LVD, RoHS Compliant N/AN/A
Model 555A3-Color Dial 0-3.5 PSID to 0-43 PSID ±5% 300 PSI Not Available N/AN/A
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