PerkinElmer Photovac MicroFID, User Manual

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MicroFID Software Manual
Flame Ionization Detector
The MicroFID uses a flame ionization detector for the measurement
of combustible organic compounds in air at parts­per million levels.
The permanent air gases (argon, carbon dioxide, nitrogen, oxygen,
water vapor, etc.) are not ionized by the flame.
When MicroFID is turned on, the display prompts you to turn on
the hydrogen. The internal pump draws air in through MicroFID’s
inlet. This sample air provides the oxygen necessary for combustion
in the hydrogen fed flame.
Electrometer
Repeller Electrode
(Jet +75 Volts)
Collector Electrode
Sample In
Exhaust Out
Flame Arrestor
Flame Arrestor
Microprocessor
Combustion Chamber
Glow Plug Thermocouple
Figure 27 Flame Ionization Detector
When the proper ratio of hydrogen to air is present in the
combustion chamber, the flame is started automatically with a glow
plug. A thermocouple is used to monitor the status of the flame.
When the sample passes through the flame the combustible organic
compounds in the sample will be ionized. After the compounds
have been ionized by the flame, the ionized particles are subjected
to a continuous electric field between the repeller electrode at the jet
(+75V) and the collector electrode.
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