VICI D-2-I - Manual (Page 21)

17
Column Connection
The following applies only to systems with the PD-D2 detector. On the
PD-D2-IS detector, the column is connected to the column inlet tube with a
1/16" union, and does not extend into the detector.
1. Make a mark on the column at the length indicated below for PDHID or
PDECD operation, as appropriate for your application. If a ruler is not
handy, place the end of the column over the figure below to determine
how far into the detector body the column must be inserted.
2. Remove the knurled nut and plug from the column inlet manifold at the
bottom of the detector. Slide the nut over the end of the column, followed
by the appropriate column ferrule (FS.4 or FS.5, or ZF.5V for megabore).
3. Insert the column through the column inlet manifold at the bottom of the
detector. Slide it in until the mark is flush with the surface of the knurled
nut, and secure the column by tightening the knurled nut finger tight only.
Figure 5 on the next page shows how the column position affects detector
performance.
Testing for Leaks
It is critical for the system to be leak-tight, and an additional check at this
point can save many headaches later on. To test for leaks:
1. On a PD-D2, insure that the dopant inlet and vent outlet are plugged.
Cap the vent outlet tube on the PD-D2-IS.
2. Pressurize the entire system with helium to 138 kPa (20 psi).
3. If the system does not hold pressure, check all the fittings with an
electronic helium leak detector. DO NOT use leak detecting liquids.
4. Tighten fittings as required. (Further leak testing is described on
page 21 in the section entitled “Checking for Leaks in the Discharge
Gas Plumbing”).
Installation
Optimum length of column insertion in PDECD mode (101 mm)
Optimum length of column insertion in PDHID mode (116 mm)