Doc. P/N:
WSP-009-004
Version:
V1.3
Issue Date: August 2013
Page 23 of 62
Operator Manual
4.8.4 Sound Speed Tab
Sound speed varies with temperature and salinity, so this changes throughout the year. Use a
temperature sensor to set the sound speed if possible. Otherwise, the operator should become
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necessary.
The
Sound Speed
tab allows you to set surface speed correction settings for fresh and sea
water. Valid values for both sea and fresh water range between 1000 and 2000 m/s.
Knowing the temperature gives a close approximation for the sound speed. In Manual mode the
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values.
Refer to the section “10.2.4 Sea Trial - Commissioning Step 11 : Sound Speed” on page 51 of
the WMB-3250 Installation Manual for full instructions.
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Convex
INCREASE
sound speed value
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Concave
DECREASE
sound speed value
Sound Speed Guide:
Ź
1500 m/s for sea water.
Ź
1435 m/s for fresh water.
Salinity values:
Ź
30-37(35) for sea water.
Ź
0-1(1) for fresh water
NMEA Temperature:
Ź
If the Surface Temperature
data window does not
display a valid temperature
value, check that the
incoming NMEA data
contains the “MTW”
sentence.
Figure 17. Sound Speed Effect and Required Corrections
Figure 18. Ship Setup Options – Sound Speed tab