6700 Portable Sampler User Manual - Isco

Distribution
Menu Charts appear in:
Figure 26, Standard Programming:
Programming
Screens on page 113
Figure 36, Extended Programming:
Equipment Setup
on page 122.
6700 SAMPLERS
Random Interval Pacing
To program the sampler for random interval pacing, enter the
length of time you want to sample. The run time is the only random
programming setting you’ll need to enter because the sampler
derives the number of sample events required for the
program from the distribution settings. (You can combine random
pacing with any distribution.) Each time you run the program,
the sampler generates a new set of random intervals. This
makes each sample event unpredictable from run to run.
In both nonuniform clock time pacing and nonuniform interval
pacing, the sampler takes a sample at the start time. For random
pacing, however, it takes the first sample at the end of the first
interval, not at the start time.
Event Pacing
To program the sampler for event pacing, select EVENT PACED
from screen 8. When prompted for the enable setting, enter the
enable settings at which you want the sampler to take samples
(see Sampler Enable on page 90).
Event pacing uses the combination of both the programmed
enable conditions and the external enable (pin F of the external
flow meter connector) to determine the enable state. Each time it
becomes enabled, the sampler takes one sample, placing it in one
bottle. The sampler must become disabled between events. The
sampler always takes a sample at the start time for event paced
programs. Nonuniform clock time programming schedules each
sample event individually. The sampler skips samples scheduled
while it is disabled.
Although you can combine flow pacing and all time pacing types
with any distribution, event paced programs by definition uses
only sequential distribution. The sampler finishes an event
paced program after depositing a sample in each bottle.
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DISTRIBUTION
Distribution describes how the sampler is to deposit samples. A
sample is the volume of liquid deposited in a bottle. A sample
event includes the full sampling cycle and may deposit a sample
into more than one bottle. You can program the sampler for five
distribution methods:
Sequential Composite
Bottles per sample Multiple Bottle Compositing
Samples per bottle
Sequential
In sequential distribution, the sampler deposits one sample in
each bottle. A sequential sample represents a “snapshot” of the
flow stream at a point in time.