Hach-Lange SD900 Refrigerated Sampler, SD900 AWRS User Manual - Manual (Page 36)

Note: NPDES requirements typically requests that the first three hours of a storm be monitored. If the flow volume
is lower than expected, flow-weighted sampling can continue for a long time as the flow rates decrease and the
sample intervals become longer.
1. Go to PROGRAM SETUP>MODIFY SELECTED>ADV SAMPLING.
2. Select STORMWATER>ENABLE.
3. Select how the program will start.
Option Description
Immediate The user starts the sampling program.
External The sampling program starts when a signal is received 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. The intervals can be different. The
sum of the intervals is equal to the total length of the stormwater collection period.
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 whether a time limit will be used.
Option Description
ENABLE The sampling program stops after a specified time. Enter the time.
DISABLE The sampling program operates until the program is complete.
Set variable intervals
Variable time intervals (hours and minutes) or flow intervals (counts) can be set for sample cycles.
Variable intervals cannot be enabled when CTVV is enabled.
1. Select PROGRAM SETUP>MODIFY SELECTED>ADV SAMPLING from the main menu.
2. Select VARIABLE INTVL>ENABLE.
3. Enter the time or count interval between each sample cycle and push ENTER to save the interval.
Up to 99 intervals can be entered.
Timed bottle sets
The timed bottle option makes a single sampler operate like multiple samplers. This option is useful
for situations such as high flow versus low flow days. The sampler is configured to start a sampling
program in multiple parts. The first part of the program starts for a user-specified time interval. The
second part then operates for a user-specified time interval, followed by the third part, etc.
The sample bottles are also divided into multiple sets. The first set of bottles is assigned to part one
of the sampling program. The second set of bottles is assigned to part two of the sampling program,
etc.
A timed bottle program can run at the same time as the storm program, setpoint sampling and
variable intervals.
When enabled with variable intervals, the timed bottle option will collect samples in each timed bottle
set based on the specified variable intervals. When a timed bottle set switch occurs upon expiration
of the trigger time, the variable interval index is reset.
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