Perkin-Elmer TITAN MPS, User Manual

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System Description
Pressure Monitoring
Each Titan MPS is equipped with the DPC™ Direct Pressure Control, a
pressure monitoring system designed to measure and report the sample
pressure in a single reference vessel. The pressure in the reference vessel is
determined by using polarized light to measure any change in the photo
elastic behavior of a glass ring in the vessel lid. This information is passed
on to the power control module, which can use the measured pressure to
regulate the output oven power. Continuously adjusting the magnetron
output in response to the pressure signal allows fine digestion control and
can prevent rupture discs from being activated.
Pressure Vessels and Turntables
All Perkin Elmer pressure vessels are manually operated. A rupture disc placed on
the vessel seal limits the interior pressure of each vessel type to a maximum
permissible value appropriate for the vessel. For all vessels, acid vapors that escape
when a rupture disc activates are guided to the Gas Containment Manifold at the
top center of the turntable. The gasses are then vented through the PFA tube
connected through the oven lid.
PerkinElmer Standard 75mL Vessels
PerkinElmer Standard 75mL vessels are made entirely of TFM™. Aside from
chemical resistance to all mineral acids including hydrofluoric acid, this ensures a
high level of mechanical strength, even at high digestion temperatures.
Note
The safety of the vessels is guaranteed by the rupture discs; pressure and
temperature measurement serve to control the digestion process, but have
no primary safety function.