GE Hydran 201i, Инструкция по эксплуатации

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Dissolved Gas Analysis (DGA)
Part 17997 Rev. 6, March 2011 13-3
If the data is read from the H201T i , follow the instructions in Section 4.5.1 on page 4-12.
The data can be collected using a host computer running the Hydran Host software (see the
Hydran Host Software Manual ).
The historic data are verified as follows:
1. Consult the historic data file Events to investigate suspicious alarms and other events.
2. Consult the historic data files Short Term and Long Term to study the evolution of
the gas level and the hourly and daily trends.
3. Ensure the hourly and daily trends periods are optimized. Change the values if
necessary.
4. Examine every alarm setting. Change the values if necessary.
Note: Alarm settings should be modified by authorized personnel only.
13.2 DISSOLVED GAS ANALYSIS (DGA)
Frequency : Annually (minimum) or on alarm
The dissolved gas analysis (DGA) is the reference method used to determine the exact level
of dissolved gases in oil. A DGA should be performed at least once a year.
To verify the readings of the Hydran 201 i System using a DGA, proceed as follows:
1. Note the Hydran 201T i ’s gas level reading.
2. Take an oil sample from the Hydran 201 sensor’s sampling port (see Appendix H).
3. Send the sample to a qualified laboratory.
The DGA results include the concentrations, in parts per million (ppm), of the following
gases:
• Hydrogen (H
2
)
• Carbon monoxide (CO)
• Acetylene (C
2
H
2
)
• Ethylene (C
2
H
4
)