PerkinElmer AVIO 200, Hardware Manual

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System Description
92
Cooling Water: System requires a flow of 1 gal/min at 310 to 550 kPa at a
temperature between 15 °C and 25 °C. A recirculating cooling system is required
(PolyScience
®
WhisperCool
TM
chiller or equivalent is recommended).
Automatic Ignition: Plasma ignition is computer controlled and totally automated.
The plasma can be turned on at a set time, warming up the system prior to an
analysis, and can be turned off automatically after an analysis.
Safety Interlocks: System checks water flow, shear gas flow, argon pressures,
emergency plasma off switch, torch compartment door interlocks, torch installed and
plasma stability. The status of these interlocks is constantly monitored and text
information is displayed on the computer screen. If any interlock is interrupted, the
plasma is shut down automatically.
Gas Flow Controls
Plasma Argon Flow: Closed-loop flow control using a proportional valve and a
measured pressure across a known resistor. Computer-controlled to regulate the flow
automatically within the range of 8 to 20.0 liters/minute in 1.0 liter/minute
increments.The flow system is interlocked to prevent ignition without plasma gas
flowing.
Auxiliary Argon Flow: Closed-loop flow control using a proportional valve and a
measured pressure across a known resistor. Computer-controlled to regulate the flow
automatically within the range of 0 to 2.0 liter/minute in 0.1 liter/minute increments.
Nebulizer Argon Flow: Computer-controlled, using a mass flow controller and is
variable between 0 and 2.00 liter/minute in 0.01 liter/minute increments.
Shear Gas: A compressed-air shear gas (18-20 liters/minute) is used to push the
plasma plume out of the optical path, minimizing the impact of self-absorption in the
cooler plasma plume.