Kongsberg Simrad SN90 Reference Manual page 581

5 From this raised position, turn the transducer towards port. The indicator arrow is
still pointing up. This is a Rotation Around Z.
6 Proceed until the requested angle has been reached.
Example: If a -100-degree Z angle is requested, the
to -100 degrees (that is the angle from the forward position). Setting it to +260
degrees will also work.
Related topics
Inserting the installation parameters, page 214
Functions and dialog boxes, page 416
Setup menu: functions and dialog boxes, page 448
Installation Parameters page, page 574
MRU (Motion Reference Unit) page
Use the (Motion Reference Unit) page to insert the physical location and rotation
MRU
of the motion reference sensor (MRU) with reference to the vessel coordinate system.
Description
The motion reference unit (MRU) measures the roll and pitch movements of the vessel.
Some sensor models also measure heave.
Note
If your SN90 system is installed with a hull unit, it is also provided with a built-in
motion sensor to provide electronic stabilization of the sonar beams. It is placed inside
the Motor Control Unit.
If you want to use the built-in motion sensor, you do not need to enter any offset values.
If the hull unit has been installed with the Motor Control Unit pointing straight aft, you
do not need to enter any rotation values. If the unit faces in any other direction you must
compensate for this by typing the relevant value for
If you do not have a hull unit you must use a separate motion sensor.
Offsets
The offset values specify the physical location of the motion reference unit relative
to the reference point (origin). The relevant offset values can normally be taken
from the vessel drawings.
Rotation
The values for rotation around the X, Y and Z axis are used to compensate for any
misalignments made during the physical installation of the motion reference unit.
Such misalignments occur if the sensor is not placed in parallel with the vessel's
horizontal and/or vertical planes. We strongly recommend that you install your
motion reference unit so that all rotation angles can be set to 0 (zero).
381294/E
Functions and dialog boxes
Rotation Around Z
.
Rotation Around Z
must be set
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