TA Instruments AR 2000, Руководство оператора

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AR 2000 Operator’s Manual 101
Step 6: Pressurizing/Depressurizing the Cell and Running
Experiments
When the cell is fully installed, it can be operated in either self-pressurization mode , in which the pressure
is due to the volatility of the sample, or in external pressurization mode , in which the pressure is provided
by an external source. The pressure achieved when the cell is used in self-pressurizing mode will depend
on the sample and temperature. As a guide, the vapor pressure of water at 150°C is about 4.76 bar (69 psi.).
When the cell has been assembled correctly as directed in this chapter, it can be pressurized. The manifold
contains a three-way valve. The three positions for the valve are shown in Figure 8.22.
Figure 8.22
Three-Way Valve Positions
Horizontal—Off
Isolation between the
pressure cell and the con-
nector block on the man-
ifold.
Vertical Down—Pressure
Build
(external pressuriza-
tion mode)
Connection between the
pressure cell and the con-
nector block on the manifold.
Vertical Up—Pressure
Relief
Connection between the
pressure cell and atmo-
sphere.