Detector response, Support equipment and consumables, Compressed gases – INFICON MicroFID II Portable Flame Ionization Detector User Manual
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Figure 2. Block Diagram
Detector Response
The MicroFID II is strictly an organic compound detector. It does not respond to inorganic compounds.
The MicroFID II
’s sensitivity is highly dependent on chemical structure and bonding characteristics. The
combustion efficiency of a compound determines its sensitivity.
Simple saturated hydrocarbons (methane, ethane etc.) possess high combustion efficiencies and are
among the compounds that produce the highest MicroFID II response. Organic fuels (acetylene, refined
petroleum products), burn easily and are also extremely well detected.
The presence of substituted functional groups (amino, hydroxyl, halogens) on a simple hydrocarbon
reduces its combustion efficiency and thus MicroFID II
’s sensitivity to the compounds methanol and
chloromethane, for example, are detectable with the MicroFID II but not as well as methane. A greater
number of carbon atoms can offset this loss of sensitivity due to substitution. For example, the MicroFID II
is more sensitive to n-butanol than it is to methanol.
NOTE: The FID Response Factors Technical Note is maintained on the INFICON web site:
Support Equipment and Consumables
Compressed Gases
Cylinders of compressed gas, such as hydrogen and calibration gas, must be handled with extreme care.
When using the calibration gas bag adapter, take care not to kink or stress the tubing. For safety, the
hydrogen and calibration gas cylinders must be secured before use.
Please observe the following handling procedures:
Do not mutilate cylinders.
Do not expose the cylinders to direct sunlight.
Do not heat the cylinders. The cylinders may rupture at high temperatures.
Use only the specified regulator for the calibration gas. Confirm regulator type and material with
your specialty gas supplier.
Use only the MicroFID II Hydrogen Filling Station for the hydrogen cylinder, Part No. A1201222.
Display and
I/O Connector
Keypad
Microprocessor
Power
Supply
Electrical Connections
Sample Flow
Pump
Sample
In
Inlet
Filter
Flame Ionization
Detector
Detector
Out