Sequoia LISST-ABS, Руководство пользователя

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14
LISST-ABS and RS232
Best practices
In order to obtain the most accurate results it is recommended
that the LISST-ABS be powered up and allowed to sample in
the automatic mode (green LED double blinking) for 30 seconds
or more before issuing a Start Measurement command. This 30
second wait should be done every time power is applied.
During these 30 seconds the LISST-ABS is obtaining a running
average of attenuation that is used internally to compute the
ACB value that is output. Shorter waits will result in noisier
measurements.
It is also recommended that bursts of 30 measurements or
more be recorded and averaged to obtain the best results.
Because of the small measurement volume of the LISST-ABS
the ACB measurements can be vary sample to sample as
clouds of turbidity pass by. In order to obtain a representative
value some averaging of these clouds should be done.
For example if measurements every 15 minutes are desired we
recommend the following procedure:
1) Power up the LISST-ABS 45 seconds before the beginning of
the desired sample time and allow it to sample.
2) Option 1: Start recording the values being output by the
LISST-ABS to record 60 measurements 1 second apart.
Option 2: Issue GetSample commands to record 60
measurements 1 second apart.
3) Power down the LISST-ABS and wait till the next sample time.
For suggestions on mounting, cleaning and maintenance
please see Section 2.6.