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Measurements Triggered by Liquid Levels or Flow
8544operations.fm
Section 4
5.
To exit the manual mode, press
CLEAR ENTRY
. This returns the sampler
to the standby state.
While the sampler is in standby, a sample cycle can be initiated by pressing
the
TAKE SAMPLE
key.
4.8 Measurements Triggered by Liquid Levels or Flow
The sampler can operate in any one of three control modes, using an external
controlling device (i.e. Liquid Level Actuator, Cat. No. 943, or an external flow
meter). In any of the three modes, the sampler remains in a standby state until
liquid at the sample source reaches a predetermined level. This feature may
be also used to access the setup of the storm water monitoring program, First
Flush. The three modes are described below:
Mode 1
The instrument collects a sample within the first minute that the liquid rises to
the predetermined level. After the first sample is taken, the sample interval
automatically resets to the programmed interval.
If the liquid falls below the predetermined level, the sampler continues
to collect samples at the programmed time or flow interval, until the
program ends.
Mode 2
The instrument collects a sample within the first minute that liquid rises to the
predetermined level. After the first sample is taken, the sample interval
automatically resets to the programmed interval. The sample program ends if
liquid falls below the predetermined level. If the liquid again rises to the
predetermined level, a sample is taken within the first minute and the interval
automatically resets to the programmed time or flow interval.
Mode 3
When the liquid rises to a predetermined level, a sample is not taken
immediately. A sample is taken only when liquid is at or above the
predetermined level and after the programmed sample interval has elapsed.
The interval between samples counts down and resets even when the liquid
level is below the predetermined (actuation) level. This mode is used to
synchronize sample collection with a real-time clock when sampling in the
time mode.
Summary of Contents for SIGMA 900
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