Defining the sound speed close to the transducer
The sound speed close to the transducer face is an important parameter for maximum accuracy. You can define the sound speed at the transducer manually, or retrieve the information from a dedicated sensor.
Context
Many users mount a sensor close to the transducer face in order to measure the sound speed. The sensor is often referred to as a sound velocity probe. If the sensor is not mounted, the sound speed information must be provided manually.
Note
The sensor is not a part of the ME70 system. This is a commercial item that can be purchased locally.
Procedure
1 Open the Setup menu.
2 Select Environment.
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Observe that the Environment dialog box opens.
3 Open the Transducer Face page.
4 Select Probe if you have a suitable sensor connected to your ME70.
By selecting Probe, the sound speed values from the sensor are received. The information is included in the raw data files.
5 Select Manual if you do not have a suitable sensor.
Specify a manual sound speed value.
6 Select Profile to set the sound speed at the transducer to the speed value from the profile at the transducer depth.
a Go to the Profile page to select the profile to be used.
b Return to the Transducer Face page.
7 Enter the sound speed value if you have selected a manual source.
8 Set the warning limit for difference in sound speed between profile and probe.
If the difference exceeds the value you have defined in the spin box, an alarm is generated. The purpose of this alarm is to notify you that you should load a new profile.
9 Select OK to save the selected settings and close the dialog box.