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Dewpoint – Transmitters

The HygroPro is a loop-powered, intrinsically safe moisture transmitter for measuring the moisture content in gases and non-aqueous liquids in pipeline natural gas, petrochemical, power generation, pharmaceutical, process, and industrial applications. The HygroPro features an aluminum oxide moisture sensor, temperature thermistor, and pressure transducer built on a single probe mount to provide real time measurements for the calculation of parameters such as ppmv in gases, pounds per million standard cubic feet in natural gas, ppmw in liquids and percent relative humidity in addition to dew point temperature.

HygroPro Specifications

Dew Point/Frost Point Calibration Ranges
  • Overall: 68°F to -166°F (20°C to -110°C)
  • Standard: 68°F to -112°F (20°C to –80°C)
Operating Temperature
  • Overall: 68°F to -166°F (20°C to -110°C)
  • Standard: 68°F to -112°F (20°C to –80°C)
Operating Temperature –4°F to 140°F (–20°C to 60°C)
Warm-Up Time Meets specified accuracy in three minutes
Calibrated Accuracy @ 77°F (25°C)
  • ±3.6°F (±2°C) from -85°F to 50°F (–65°C to 10°C) dew/frost point
  • ±5.4°F (±3°C) from –112°F to –86°F (–80°C to –66°C) dew/frost point
  • ±0.9°F (±0.5°C) from –85°F to 50°F (–65°C to 10°C)dew/frost point
  • ±1.8°F (±1.0°C) from –112°F to –86°F (–80°C to –66°C)frost point
Response Time Less than five seconds for 63% of a step change in moisture content in either wet-up or dry-down cycle


  • 12 to 30 VDC (loop-powered, customer supplied)
  • Output: 4 to 20 mA analog, RS485 digital
  • Output Resolution: 0.01 mA/12 bits
  • Max R = (PSV x 33.33) – 300 Example: (24 x 33.33) – 300 = 500 O
  • Cable: 6 ft (2 m), standard (consult factory for custom lengths); cable includes molded weatherproof connector with flying leads
  • 128 x 64 LED backlit LCD
  • Display from one to three parameters and diagnostics


Sample Connection
  • 3/4-16 in (19 mm) straight male thread with O-ring
  • G 1/2 with optional adaptor
Operating Pressure 5 :Hg to 5000 psig (345 bar)
Enclosure Type 4X/IP67
Dimensions (h x w x d)
  • Overall: 7.88 in x 3.99 in x 2.56 in (200 mm x 101 mm x 65 mm)
  • Weight: 1.2 lb (550 g)
European Compliance Complies with EMC Directive 2004/108/EC and PED 97/23/EC for DN<25
Hazardous Area Certification
  • C_US Class I, Division 1, Groups A,B,C&D, Type 4X
  • II 1 G EEx ia IIC T4 (ATEX)
  • Ex ia IIC T4 (IEC Ex)

Moisture Sensor

Sensor Type Thin-film aluminum oxide moisture sensor
Calibration Each sensor is individually computer-calibrated against known moisture concentrations, traceable to NIST.
Calibration Interval Sensor recalibration by GE is recommended every six to twelve months depending on application.
Flow Rate Gases: Static to 100 m/s linear velocity at 1 atm

Built-In Temperature Sensor

Type NTC thermistor
Operating Range -22°F to 158°F (-30°C to 70°C)
Accuracy ±0.9°F (±0.5°C) overall
Response Time (Maximum) One second in well stirred oil or 10 seconds in still air for a 63% step change in increasing or decreasing temperature

Built-In Pressure Sensor

Type Solid state/piezoresistive
Available Ranges
  • 30 to 300 psig (3 to 21 bar)
  • 50 to 500 psig (4 to 35 bar)
  • 100 to 1000 psig (7 to 69 bar)
  • 300 to 3000 psig (21 to 207 bar)
  • 500 to 5000 psig (35 to 345 bar)
Accuracy ±1% of full scale (FS)
Pressure Rating Three times the span of the specified range to a maximum of 7500 psig (518 bar)

HygroPro is suitable for a variety of applications, including:

  • Pipeline natural gas
  • Petrochemical
  • Power generation, pharmaceutical
  • Process
  • Industrial applications


The MMY30 is specifically designed to measure dew point or ppm at line pressure or atmospheric pressure for control of desiccant air dryers. These benefits apply to both dryer users and manufacturers.

  • Simple, 4-20 mA two-wire connection
  • Fast response planar sensor
  • Integral filtering and flow regulation
  • Trouble-free indoor or outdoor mounting
  • Field calibration with the optional DewComp(MCY40)
  • Microprocessor in NEMA 4X (IP66) enclosure
  • FM approval (Class 1) – Division 2 standard

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The MMY31 mounts directly in-line for applications such as glove boxes, where a bypass is not appropriate. It is easily installed via a 1/2″ MNPT or G 1/2 adjustable insertion length compression fitting. Applications include glove boxes, environmental chambers, and high altitude testing.

  • 4 to 20 mA loop-powered 1/2″ MNPT or G 1 / 2 process connection Planar capacitive sensor
  • Class 1, Division 2 standard

coming soon

coming soon

coming soon

Veridri Moisture Transmitter

The Veridri Moisture Transmitter provides Dryer Manufacturers and other OEM’s with the means to make simple accurate and reliable moisture measurements with a wide variety of Dewpoint ranges.
  • 4 to 20 ma loop powered
  • 3/4-16 Straight thread with optional 3/4″ NPT adapter
  • Thin Film Aluminum Oxide Technology
  • General Purpose