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Dwyer 3100MRS Photohelic Switch/Gauge 0 to 100 inch
Dwyer 3100MRS Photohelic Switch/Gauge 0 to 100 inch

Dwyer 3100MRS Photohelic Switch/Gauge 0 to 100 inch

Dwyer 3100MRS Photohelic Switch/Gauge 0 to 100 inch Specification

  • Outer Size
  • Standard 4 (101.6 mm) Dial
  • Seal Material
  • Buna-N
  • Display
  • Analog Dial with photohelic indicator
  • Grade
  • Industrial Grade
  • Sensor Type
  • Differential Pressure Sensor
  • Thread
  • 1/8 NPT Female
  • Bourdon Tube
  • Not Applicable (Diaphragm-based)
  • Material
  • Die-cast Aluminum Case
  • Dial Material
  • Acrylic
  • Pointer Material
  • Aluminum
  • Processing Type
  • Precision-Machined
  • Diameter
  • 4 inch (101.6 mm)
  • Glass Size
  • 105 mm
  • Mount Type
  • Flush or Surface
  • Scale Range
  • 0 to 100 inch w.c.
  • Accuracy
  • 2% of full scale
  • Finishing
  • Matte Grey Enamel Finish
  • Measure Pressure Of
  • Air and compatible gases
  • Accessories
  • Mounting hardware, instruction manual
  • Repeatability
  • ±1% of FS
  • Enclosure Rating
  • NEMA 1 (IP20)
  • Weight
  • 1.35 kg approx
  • Power Consumption
  • No external power required for gauge, switch uses circuit power
  • Mounting Orientation
  • Vertical (standard)
  • Case Depth
  • 5.5 inch (139.7 mm) approx.
  • Switch Type
  • DPDT snap action
  • Response Time
  • 1 second max
  • Operating Temperature Range
  • -18 to 60°C (0 to 140°F)
  • Voltage Rating
  • 250 VAC max
  • Electrical Rating
  • 10A @ 120/240 VAC (resistive)
  • Window Material
  • Polycarbonate
  • Compliance
  • RoHS Compliant
  • Contact Material
  • Silver alloy
 

Dwyer 3100MRS Photohelic Switch/Gauge 0 to 100 inch Trade Information

  • Payment Terms
  • Cash on Delivery (COD), Cash Against Delivery (CAD), Cash Advance (CA), Cash in Advance (CID)
  • Main Export Market(s)
  • Asia
  • Main Domestic Market
  • Chandigarh, Himachal Pradesh, Andaman and Nicobar Islands, Nagaland, Chhattisgarh, South India, North India, East India, Assam, Arunachal Pradesh, Bihar, Delhi, Gujarat, Goa, Haryana, Jammu and Kashmir, Jharkhand, Karnataka, Madhya Pradesh, Maharashtra, Mizoram, Meghalaya, Manipur, Odisha, Punjab, Pondicherry, Rajasthan, Sikkim, Tamil Nadu, Telangana, Tripura, Uttar Pradesh, West Bengal, Uttarakhand, Daman and Diu, Dadra and Nagar Haveli, Lakshadweep, Andhra Pradesh, Kerala, Central India, West India, All India
 

About Dwyer 3100MRS Photohelic Switch/Gauge 0 to 100 inch

Dwyer 3100MRS Photohelic Switch/Gauge 0 to 100 inch

 

Series 3000MR/3000MRS Photohelic® Switch/Gage

Combines Differential Pressure Gage with Low/High Set-Points,Compact Size

 

 ModelDescription 
 3100MRS-100 inchPressure Switch/Gage,Range 0-100 inch, 2.0 minor divisions.
 

 

Includes

  • mounting ring, snap ring
  • 18" cable assembly
  • (2) 3/16" tubing to 1/8" NPT adapters
  • (2) 1/8" NPT pipe plugs
  • (4) 6-32 x 1-1/4" RH machine screws (panel mounting)
  • (3) 6-32 x 5/16" RH machine screws (surface mounting)

he Series 3000MR Photohelic® Switch/Gage combine the functions of a precise, highly repeatable differential pressure switch with a large easy-to-read analog pressure gage employing the durable, time-proven Magnehelic® gage design. Switch setting is easy to adjust with large external knobs on the gage face. Gage reading is unaffected by switch operation - will indicate accurately even if power is interrupted. Solid state design now results in greatly reduced size and weight. Units can be flush mounted in 4-13/16" hole or surface mounted with hardware supplied. 3000MR models employ versatile electromechanical relays with gold over silver contacts - ideal for dry circuits.

Gage accuracy is ±2% of full scale and switch repeatability is ±1%. Switch deadband is one pointer width - less than 1% of full scale. Compatible with air and other non-combustible, non-corrosive gases, they can be used in systems with pressures to 25 psig.

Applications

  • Fan Control
  • Damper Control
  • Environmental Pollution Control

Approvals

  • CE Approval
  • GOST-R Certificate

Specification

Service Air and non-combustible, compatible gases 
Accuracy ±2% of FS at 70°F 
Pressure Limits -20" Hg to 25 psig 
Temperature Limits 20 to 120°F 
Process Connections 1/8 female NPT (duplicated side and back) 
Size 4" dial face, 5" O.D. x 3-1/8" 
 Weight1.8 lb 
 Switch Specifications 
 Switch TypeEach setpoint has 1 Form C relay (SPDT) 
 Relay Contacts(resistive load) 1 Form C rated 1.0A @ 30 VDC, 0.3A @ 110 VDC or 0.5A @ 125 VAC. Gold over clad silver - suitable for dry circuits 
 Electrical Connections18" cable assembly with 8 conductors 
 Power Requirements24 VDC, regulated ±10% 
 Mounting OrientationDiaphragm in vertical position 
Set Point Adjustment Adjustable knobs on face 
 Agency ApprovalsCE 


Reliable Differential Pressure Monitoring

The 3100MRS provides exceptional measurement accuracy (2% FS) and repeatable results (1% FS), making it ideal for process control in HVAC systems, cleanrooms, or filtration setups. Its diaphragm-based sensor ensures accurate readings while the analog dial offers instantaneous visibility. This model supports both visual monitoring and electrical switching within a rugged industrial-grade enclosure.


Versatile Mounting and Durable Design

Engineered for practical installation, the gauge suits both flush and surface mounting orientations. Its die-cast aluminum case, polycarbonate window, and matte grey enamel finish deliver robust resistance to challenging environments. The NEMA 1 (IP20) enclosure limits dust ingress but is best used indoors. Supplied with necessary hardware and an instruction manual, implementation is straightforward across many industrial applications.

FAQs of Dwyer 3100MRS Photohelic Switch/Gauge 0 to 100 inch:


Q: How is the Dwyer 3100MRS Photohelic Switch/Gauge typically used in an industrial setting?

A: This gauge is employed to measure and control differential pressure for air or compatible gases, making it suitable for monitoring HVAC systems, filters, or cleanroom environments. Its integrated snap-action switch enables automatic or remote control of alarms, fans, or other equipment based on pre-set pressure thresholds.

Q: What is the process for installing the Dwyer 3100MRS, and what mounting options are available?

A: Installation is facilitated by the included mounting hardware and instruction manual. The device can be mounted either flush or on a surface, with vertical orientation recommended for optimal performance. The unit features a 1/8 NPT female thread for secure connection to your pressure lines.

Q: What benefits does the photohelic switch/gauge design offer over traditional pressure gauges?

A: The integrated photohelic design combines precise analog pressure indication with the ability to trigger control functions via DPDT snap-action switches. This dual functionality improves operational efficiency, offering both monitoring and automated response within a single durable device.

Q: Where should the 3100MRS Photohelic be installed for best results?

A: For accurate functioning, the unit should be installed indoors in a clean environment, away from excessive moisture or dust. The vertical mounting orientation ensures the gauges diaphragm remains properly aligned for reliable performance.

Q: What maintenance is required to ensure long-term operation of this gauge?

A: Routine inspection of the analog dial, electrical contacts, and connection ports is recommended. Regular cleaning of the polycarbonate window and checking mounting hardware for tightness will help maintain accuracy and longevity. No calibration is needed unless specified by your process requirements.

Q: When is it necessary to adjust the set points for the DPDT snap-action switches?

A: Set points should be adjusted whenever process requirements change, such as shifts in the desired pressure differential for alarms or control equipment. Adjustments can be made easily using the front-panel controls without the need for specialized tools.

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