CEM Discover SP-D, Руководство по эксплуатации

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Load, Save, and Create a New Method
The “Load, Save, and Create a New Method” screen allows all users to create new methods, save them to the Discover
data base and Load (recall) the methods at a later time. From this screen, the user can also recall data from a reaction
previously run on the Discover system. To access this screen press the Discover key on the Discover keypad.
Create a New Method
The Discover System has three (3) control options for programming a method – Standard, Dynamic and Ramp-to-
Temperature. These options permit the user to control how the system applies the microwave energy to the reaction.
In all control options, the user inputs control parameters to create the method. The user enters more control information
as the level of control increases. The Standard control option is the recommended control technique for routine operation.
The Dynamic method allows the user to implement the ActiVent feature. The SP-D Clinical system permits the user to
release unwanted gaseous byproducts from the reaction to prevent over pressurization and vial failure from gaseous
buildup. This ensures safe handling of the vial during and at the end of the reaction. The ActiVent safely bleeds the
solvent/vapor from the reaction vessel and releases it through the vent tube connected to the back of the system and into
a controlled environment.
If the reaction generates a gaseous byproduct or an extreme amount of pressure during the reaction, the ActiVent will
vent at a specific set point for a pre-determined number of times.
•
The “Delta Pressure” is the assigned amount of pressure to drop from the pressure set point. A delta of 50 PSI
(1.7 BAR) is recommended.
•
The “PressureSP” is the pressure set point at which the venting will begin. If the gaseous byproduct that is
generated is the only pressure in the reaction vial (the reaction temperature does NOT exceed the boiling point of
the solvent), the ActiVent pressure release can be set below the control point. If a gas is generated, but some of
the pressure is due to vapor pressure, then the release point for the ActiVent must be set at or above the
pressure control point.
•
The “Times at SP” is the maximum number of times a reaction will vent during the assigned ramp and hold time.
However, this parameter can be adjusted based on specific reaction conditions. For a typical reaction, 5 vents
are recommended.
CAUTION
If the reaction temperature exceeds the acid boiling point and too many venting actions are performed, the vial
could become dry and superheat.
•
The number of stages is the stage at which the PressureSP will be active for a multistage method. A maximum of
5 stages can be added.