Campbell PVS5120 Series, Инструкция по эксплуатации

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PVS5120-Series Portable Samplers
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7.2 Sampler Components
7.2.1 Sample Volume Adjustment
FIGURE 7-4. Metering chamber and volume control tube
Setting the desired sample volume is accomplished by adjusting the height of
the volume control tube within the metering chamber (FIGURE 7-4 ). The tube
mounts through the top of the chamber with a gland nut fixing the position. To
adjust the sample volume, loosen the nut until the volume control tube moves
freely. Raise or lower the bottom end of the tube to the desired volume using
the lines provided on the side of the metering chamber as a guide (lines are
spaced at 100 mL intervals with the exception of one at 50 mL). Tighten the
gland nut to hold the volume control tube at the desired position.
The sampler has a volume accuracy/repeatability of ±2% or ±2 mL. If an exact
amount of liquid is required for a sampling protocol, the user should manually
collect a few samples to ensure that the rod is set at the correct location. For
example, a user wants to collect 400 mL samples. The user manually collects
several samples, and each of the samples has a 380 mL volume. The user
adjusts the volume control tube up, and manually collects more samples. This
process is repeated until the volume manually collected is ~400 mL. The
volume control tube is then tightened in place. Once the liquid
sensing/conductivity rod is tightened, the sample should be within ±2% or
±2 mL of the desired volume.
The volume control tube should always be located below the
liquid sensing/conductivity rod.
Hold the bottom nut while loosening or tightening the top nut, or
it may become loosened from the metering chamber cover and
create an imperceptible leak in the vacuum system.
CAUTION
NOTE