Campbell Scientific CVS4200 / BVS4300 Stationary Samplers - Manual (Page 26)

CVS4200 / BVS4300 Stationary Samplers
sample). TABLE 5-5 outlines the key changes made to the sampler for a
sanitary system.
TABLE 5-5. Sanitary System Changes
Component Standard Material Sanitary System Material
Intake Tube PVC Teflon-Lined PVC
Sinker/Strainer Lead Sinker Stainless Steel Sinker/Strainer
Fittings Brass Stainless Steel
Metering Chamber Acrylic Pyrex
Metering Chamber Cover Delrin Teflon with Steel Bracing Ring
Discharge Tube Latex Silicone
Sample Container(s) HDPE (or polypropylene (PP)) Glass
O-Rings Buna-N (or Viton) Silicone
5.5.3 Pressurized Source
Special care must be taken in applications with back pressure so that the
sampler does not become flooded. Options for pressurized situations include:
1. Relocate the sampler. Although it may be located farther from the
source, the CVS/BVS vacuum system is able to handle long draws and can
be moved to a location (higher) where back-pressure is not an issue.
2. Looping the intake tube. For small amounts of pressure, looping the
intake tube up to a height that the water pressure cannot push above is a
simple way of getting around the issue. The maximum height would be
the maximum vertical draw, 3.4 m (27.5 ft).
We recommend using a valve with external valve control in this
kind of situation, to be on the same side. See FIGURE 5-8
.
NOTE
FIGURE 5-8. Vertical loop for pressurized source
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