PerkinElmer aanalyst 200 User Manual page 82

System Description
The Burner Mount
The quick change burner mount provides horizontal, vertical, and rotational adjustment. The
quick-disconnect release lever simplifies removal of the burner assembly.
The Ignitor Assembly
The ignitor assembly includes the glow plug, the ignitor solenoid and ignitor arm, the burner head
interface circuit, and the flame detect circuit. When the ignitor is activated (automatically), the
glow plug is energized and heats up. The ignitor solenoid, which is also energized, swings the
ignitor arm into place. The ignitor arm is a gas-capture tube through which the gases flow from
the burner to the glow plug. The gases in the tube are ignited by the heat of the glow plug, which,
in turn, ignite the flame at the burner head slot.
The gas controls
The gas controls provide control of the flow rates of the fuel gas (acetylene) and the oxidant (air
or nitrous oxide).You select the gas flow rates and optimize the flame via the touch screen.
The gas control system is incorporated in the spectrometer. The system includes safety interlocks
for the flame. If the fuel or oxidant pressure falls below a minimum value the flame is shut down
in a safe sequence. The system also includes automatic sequencing of the gases when the nitrous
oxide-acetylene flame is ignited or extinguished.
The burner will be shut down in a safe sequence in the event of a power failure.
NOTE: In case of emergency, use the red emergency button located on the upper left hand side of the
instrument.
The drain system
During flame operation, measurement solution that condenses out in the spray chamber runs to
waste through the siphon interlock drain trap and is collected in the drain vessel.
The siphon interlock drain trap is integral with the burner end cap and includes an internal trap to
make certain that back pressure is applied to the burner chamber. This ensures that a fuel/oxidant
mixture cannot enter the drain vessel. There is a magnetic float in the drain trap that shuts down
the flame if the drain system is not functioning properly. If the liquid level in the trap is too low,
the switch is activated and the flame is shut down.
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