Kolida SDE-28S, Руководство пользователя

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Survey Setting
—click this option, there is a dialog pop-up, the draught value, sound velocity,
shallow alarm and echo alarm parameters can be set on this dialog.
Fig.3-7 Survey setting
1,
Draught
, it is the depth of transducer sank into water, the value should be measured from the
water surface to the bottom of transducer. The draught is about 0.5m usually, however, to prevent
the fake depth caused by bubbles generated by the movement of transducer in the water, the
draught should be increased if the ship speed is too fast.
2,
Velocity
, this is the sound velocity, in different seasons and different waters (including
different temperature) will have a different velocity, the velocity of fresh water and sea water are
different, so requests to check the echo sounder before each measurement. There are various
ways for this check, but the common is two ways: one is Check bar which will be introduced in
followed sections. The other way is to measure the sound velocity by sound velocimeter on the
spot
，
sound velocimeter not only measure the sound velocity but also the water depth, then
together with the water temperature and depth the user can get the sound velocity after
calculation
，
then input this sound velocity into the software.
The following table is a reference sound velocity according to the different temperature.
Temperature
（
℃
）
Sound velocity
（
m/s
）
Temperature
（
℃
）
Sound velocity
（
m/s
）
Temperature
（
℃
）
Sound velocity
（
m/s
）
0 1402.74 18 1476.35 36 1522.06
1 1407.71 19 1479.55 37 1523.93
2 1412.57 20 1482.66 38 1525.74