DewPro MMY245
Installation and Operation Manual
GE General Eastern
4
1.2 System
Description
1.2.1 Portable Trace Moisture Analyzer
The DewPro
MMY 245 Moisture Analyzer is designed primarily as a portable moisture instrument
that can be used in a variety of gaseous applications. The portable unit can be used to quickly spot
check the performance of dryers for compressed air, natural gas. Checking pure gas supplies, accurately
testing SF6 gas in high power switchgear and transformers, gasified LNG, breathing air or oxygen and
many other applications are easy with the MMY 245 portable analyzer.
This is a well balanced, compact, easy to use versatile analyzer complete with all the units of measure
and connectability required to keep track of the moisture critical processes in your facility. The rugged
DewPro
MMY 245 case has been selected to provide the maximum protection for the internal
components in most any industrial environment where it is used.
With the MMY 245 Portable Moisture Analyzer, measurement time is typically 5 minutes. The sensor
is kept in a very dry desiccated environment with the dry-down taking place while the instrument is
inactive or being transported to the next measurement point. For complete instrument specifications,
see Section 6.
1.2.1.1 Versatility
The variety of applications in which the DewPro
MMY 245 can be used is limited only by its range of
operation for moisture and pressure and by the chemical nature of the gas sample. The unit is designed
to be used for dry samples having a dew point temperature below freezing at the pressure of the sample
introduced to the unit. Some typical applications are listed below:
Desiccant dried air
Dried Natural Gas
Argon gas for welding
Nitrogen gas supplies
Breathing air
SF
6
gas for switchgear
Helium gas supplies
Oxygen gas supplies
Hydrogen cooling loops
Instrument air
Glove box gas purifier loops
Ethylene Production
Heat treating atmosphere
generators
Gas Bottle filling operations
… and many others.
The processes listed above often require many different units of measure and the MMY 245 is able to
provide readouts in most of the common units necessary for these applications. The unit of measure is
simply selected from the operating keypad. An optional pressure sensor will automatically correct for
changes in pressure that occur in a given stream or when spot-checking several sample points
throughout a facility or process.
1.2.1.2 Safety
The DewPro
MMY 245 has been designed to meet or exceed the FM requirements for Class I,
Division 1 environments for portable instruments.
1.2.1.3 User Friendly Operation
The normal method of measurement is to connect the DewPro
MMY 245 to the process sample tap via
a short flexible high-pressure hose that employs a quick-connect fitting. The sample valve on the
process piping is opened to start a sample flow to the unit. After allowing the sample flow to purge the
hose for 15-30 seconds, the handle on the side of the analyzer is rotated up to the vertical position. This
directs the sample across the sensor. The power button is pressed and the readout provides the moisture
value in the desired unit of measure.
The analyzer is programmed using the keypad and a matrix to select the moisture unit of measure,
temperature unit of measure and other operating parameters. An optional pressure sensor can provide
real time correction for concentration units of measure. In lieu of the optional sensor, a pressure
constant can provide the proper value with known pressure conditions.
