Initial Considerations; Operating Range; Operating Environment; Operating Requirements - GE MG-101 User Manual

1.3 Initial Considerations

This section presents some general guidelines to ensure accurate results with the MG-101.

1.3.1 Operating Range

While the driest dew/frost point temperature capability specified for the MG-101 is -75°C (-103°F), the actual limit is
determined by the moisture content of the dry nitrogen source and by the ambient temperature.
The driest dew/frost point temperature the MG-101 can produce is the dew/frost point temperature of the dry nitrogen
source plus 25°C (45°F). If dry nitrogen of this quality is not available, please contact GE Sensing for assistance. The
wettest dew/frost point temperature that can be generated is determined by the ambient temperature, and it must be at
least 10°C (18°F) below the ambient temperature.

1.3.2 Operating Environment

The MG-101 is designed to be used indoors or in an environment where ambient temperature changes are not extreme
and where the instrument will not be subject to dramatic heating or cooling. It is important to ensure that the
temperature of the calibrator and especially the saturator bottle will not change between the beginning and the end of
the calibration cycle.
IMPORTANT: Changes in the saturator bottle temperature after the calibration parameters have been established will
cause errors in the generated dew/frost point temperature.
CAUTION! The MG-101 can be damaged by freezing. Do not operate it in freezing temperatures.

1.3.3 Operating Requirements

You will need the following additional equipment to set up and operate the MG-101 calibrator:
•
Nitrogen, preferably from a liquid source
Note: Nitrogen gas cylinders may be used, but the supply gas must be at least 25°C (45°F) drier than the driest
dew/frost point temperature to be generated. Two nitrogen cylinders connected in parallel and plumbed to the
inlet of the MG-101, will increase the stability of the gas supply.
•
Stainless steel pressure regulator to set the inlet pressure to 55 psig
•
1/4" OD stainless steel tubing
•
An appropriate test chamber
Note: GE Sensing Sample Cell #2830 is preferred for M2 Type probes
•
A hygrometer to monitor the moisture sensor for either:
•
the dew/frost point reading, if simply verifying the moisture sensor performance, or
•
the sensor output signal, if generating a new calibration curve
Note: The hygrometer used for the calibration can be either a dedicated instrument for use only with the moisture
generator or the process instrument that will be used with the recalibrated sensor after the calibration is
completed.
MG-101 User's Manual
Chapter 1. General Information
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