GE Sensing MMY31 Specifications

GE

Sensing

Features

DewPro

®

MMY31

Dew Point Transmitter

The DewPro MMY31 measures dew point or ppmvin
gases. It is a cost-effective, loop-powered dew point
transmitter designed for “in-line” installation where trace
moisture measurement is required. The planar aluminum
oxide sensor provides excellent corrosion resistance,
longer calibration stability, quick response times, and an
exceptionally low temperature coefficient.

The DewPro MMY31 mounts directly in-line in your
process gas, where a bypass installation is not
appropriate. It is easily installed via a variety of
adjustable insertion length compression fittings. The
optional integrated display with user interface provides
full programming and diagnostic capability.

Applications include glove boxes, environmental
chambers, test chambers, and other locations where
direct insertion is required.

DewPro MMY31 is a General Eastern
product. General Eastern has joined
other GE high-technology sensing
businesses under a new name

_

GE Industrial, Sensing.

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• Loop-powered, 4 to 20 mA transmitter

• Fast response planar aluminum oxide sensor

• Trouble-free indoor or outdoor mounting

• Field validation with the MMY245 moisture analyzer

• Microcontroller electronics in Type 4X/IP67 enclosure

Options

• Integrated display with user interface

• FM approved intrinsically safe/explosion-proof,
Class I,II,III, Division 1 and 2, Groups A,B,C,D,E,F&G
hazardous (classified) locations

• English or metric fittings

• External display available with loop-power supply
and alarm contacts

GE

Sensing

©2005 GE. All rights reserved.
920-065A

All specifications are subject to change for product improvement without notice.
DewPro®is a registered trademark of GE. GE®is a registered trademark of General
Electric Co.

DewPro MMY31
Specifications

g

www.gesensing.com

Sensing Element

Planar aluminum oxide sensor

Measurement Range

-130°F to 50°F (-90°C to 10°C) dew point temperature;
0 to 10 ppmv, 0 to 1000 ppmv(fully adjustable with integral
display)

Recommended Recalibration Cycle

12 months, depending on the application

Calibration Accuracy

±3.6°F (±2°C) dew point at 77°F (25°C)

Maximum Sensor Relative Humidity

50% at dew point temperatures >32°F (>0°C)

Operating Temperature Range

Process: -40°F to 122°F (-40°C to 50°C)
Electronics: -40°F to 185°F (-40°C to 85°C)

Element Filter

100 micron, sintered stainless steel

Standard Operating Pressure

0 to 1750 psig (0 to 120 bar, 12 MPa)

Helium Leak-rate

<10-6mbar 1/s

Output

4 to 20 mA loop-powered, 16

:A resolution

Electronics

Microcontroller operated

Optional Display

Four-digit numeric display with bar graph and matrix
position indication. Four user interface keys for unit
selections, output adjustments and ranging.

Power Supply

24 VDC nominal, 12 to 30 VDC

Protection

Type 4X/IP67

Weight

3.3 lb (1.5 kg)

Probe Tube

316 stainless steel, 1/2 in (12.7 mm) diameter, insertion
length 2 in (50 mm) to 3.5 in (90 mm)

Typical Probe Mounting

1/2 in NPT-M, 3/4 in NPT-M, 3/4-16 O-ring, G 1/2
compression fittings. Others available, consult factory.

European Compliance

Complies with EMC Directive 89/336/EEC and
PED 97/23/EC for DN< 25

Optional Certifications/Approvals

• FM IS Class I,II,III, Division 1, Groups A,B,C,D,E,F&G, T5

• FM XP-IS Class I, Division 1, Groups A,B,C&D, T5

• FM NI Class I, Division 2, Groups A,B,C&D, T4A
DIP Class II,III, Division 1, Groups E,F&G, T5

• ATEX II 3G EEx nA IIC T4

5.44 in

(138.0 mm)

9.41 in

(238.9 mm)

3.11 in

(79.0 mm)

5.953 in

(150.9 mm)

Epoxy-coated
cast
aluminum
housing that
meets
Type 4X/IP67
requirements

M20 or
1/2 in NPT
conduit or
cable
gland

Optional
sintered
end cap

.50 in

(12.7 mm)

DewPro MMY31 with display option