Advanced sampling – Hach-Lange SIGMA SD900 Refrigerated Sampler and All Weather Refrigerated Sampler User Manual User Manual
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Advanced sampling
multiple samples) at timed interval(s). The number of bottles
segregated for the first flush sample is selectable. Concurrently,
flow-weighted samples are collected from the beginning of the
storm until all remaining bottle(s) are filled, or after a user
selected time has elapsed.
Procedure:
1. Select
PROGRAM SETUP
>
MODIFY SELECTED
>
ADV SAMPLING
from the main menu.
2. Select
STORMWATER
>
ENABLE
.
3. Select whether the program will be started immediately or from
an external device:
•
Immediate—program starts when
RUN
is pressed and
START
is selected.
•
External—program starts when signaled by an
external device.
4. If configured for a single bottle, enter the number of first flush
(FF) samples to collect.
5. If configured for multiple bottles, enter the number of bottles to
be used for first flush collection.
6. Enter the multi-bottle distribution mode (
•
Samples per bottle: more than one sample is collected in
each bottle
•
Bottles per sample: more than one bottle is used to collect
each sample.
7. Enter the number of samples per bottle or bottles per sample.
8. Enter the time interval between each first flush sample cycle.
Variable intervals may be entered, or the same time may be
entered for each interval. The sum of the intervals is equal to
the total length of the stormwater collection period. First flush
samples are usually collected within 30 minutes of a storm.
Note: The number of intervals is determined by the number of bottles
and the distribution mode.
9. Enter the volume of each first flush sample.
10. Select
ENABLE
to set a time limit for stormwater collection.
Enter the program time limit. The program will stop when this
time limit is reached.
Select
DISABLE
to allow the program to run until complete
without a time limit.
NPDES requirements typically request monitoring for the first
three hours of a storm. If the flow volume is lower than
expected, flow-weighted sampling could continue for some time
as flow rates drop and sample intervals become longer.