PerkinElmer Photovac MicroFID, User Manual

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MicroFID Software Manual
Action: Ensure there is an adequate supply of oxygen, If
you are sampling very high concentrations it is possible you are
sampling above the flame out concentration. The flame out
concentration for methane is approximately 52,000 ppm (5.2%
methane in air).
A minimum of 17% oxygen is required to start the
hydrogen flame. The oxygen is supplied from the sample as it is
drawn in by the pump. A minimum of 10% oxygen is required to
maintain the hydrogen flame
Flame out may also occur when sampling enclosed
or confined spaces where vapors and gases cannot escape. Watch
for indications of increased flame height such as erratic readings or
sudden high concentrations followed by a flame out fault.
If you will be using the MicroFID in a highly
contaminated area where it is possible that the oxygen content is
below 10%, watch for indications of reduced flame height such as
lowered detection limits or a flame out fault.
Cause: High concentrations of flammable gases (gases within their
flammable range) are present. High concentrations of flammable
gases can act as an additional fuel source. When this happens, the
flame height may increase beyond the confines of the combustion
chamber. The hydrogen supply will then be cut off and the flame
will go out.
Action: Move to a location where
there is an adequate supply of air and restart the
flame. See the information above. Watch for
indications of increased flame height such as
erratic readings or sudden high concentrations
followed by a flame out fault.
Cause: Exhaust port is blocked.
Action: At low temperatures, water vapor, a by­product
of the hydrogen flame, may condense at the
exhaust port. At sub­zero temperatures the
water vapor will freeze and obstruct the exhaust
port. If the exhaust port becomes obstructed,
pump operation will be inhibited. Flame out
may also result. Operate MicroFID within the
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