January 2014 - TD 302 Operating Manual for Pressure 4117/4117R Tide 5217/5217R, Wave & Tide 5218/5218RPage 47
PT coeffs 0,1,2,3,4
and
Temp coeffs
holds the calibration data needed to convert from raw data to engineering
values. The sensors are calibrated at delivery; if these settings are lost AADI Service Department will provide the
calibration data.
7.1.6
Additional configuration of the Tide Sensor and Wave and Tide Sensor
Set the
Enable Tide
to
Yes
to include this parameter in the output string.
Set the
Tidal Average Period
in seconds (default is 40 seconds). The minimum averaging time is 10 seconds; the
maximum averaging time is 8 minutes, refer chapter 1.3.
Set the
Air Pressure, Local gravity
and
Salinity
at the deployment site. These properties are used in calculations of
the tide parameters and wave parameters, refer Table 1-2, Table 1-3 and Table 1-4. At delivery, these parameters
are set to 101.3 kPa (Ambient Air Pressure), 9.81 m/s
2
(Local Gravity), 35.0 psu (Salinity). Air pressure variations of 5
kPa gives approximately 50 cm variation in the tide level parameter. The equation for calculating the water density is
only accurate for salinity values between 2 and 42.
The
Installation Depth
property can be used for referring the Tide Level to a chosen datum (reference level). Set this
property to the distance in meters from the datum to where the sensor is installed.
Set the
Enable high sample rate
to
Yes
to sample at 4 Hz rate. The factory setting is
No
(which means 2 Hz sampling
rate).
Set the
Enable Wave
to
Yes
to include these parameters in the output string (Wave and Tide Sensor).
Set the
Number of Samples
to be collected for wave calculations, refer chapter 1.3 (Wave and Tide Sensor). Wave
parameters are calculated with better accuracy if the number of pressure samples is high. If you select 2048 samples,
the sensor averages two frequency spectrums each of 1024 samples.
Set the property
Enable Spectrum
to
Yes
to
present the spectrum elements in the output string. The spectrum is
presented as the value of each frequency component in the wave spectrum. Spectral components outside of the
calculated
cut-off
frequencies are set to 0. When in
Smart Sensor Terminal
mode the XML output format can be
access when in
Polled
mode or when in
AADI Real-Time
mode using Aanderaa’s Real-Time Data Collector software
XML Output is enabled and the spectrum info length, freq. resolution etc are shown, refer chapter 7.2.10 XML
Commands (Wave and Tide Sensor) Table 1-4;
Note! When the Wave & Tide sensor is
connected to a SeaGuard instrument we recommend that you enable wave spectrum and/or pressure time series only
for short deployments due to current drain and memory usage. The output update interval will be at least 10 seconds
for AiCaP applications, and at least 1 minute for RS232/RS422 operation.
Set the property
Enable Pressure
Series
to
Yes
to present the Pressure Time Series and Last Pressure Sample Index.
The Pressure Time Series is the sample set used for the spectrum and wave calculation. (Wave and Tide Sensor only).
Set the
Distance to seafloor
as the distance between the sensor and the seafloor in meters. The value is used in
wave calculations. For values below 50 meters, you can set the value to 50 meters. Set the property to 0 (default) if
the sensor is deployed on the seabed (Wave and Tide Sensor).
