Setting up the input from a motion reference unit (MRU)
The information from a motion reference unit (MRU) (normally heave, roll and pitch information) is imported into the ME70 system to increase the accuracy of the echo data.
Prerequisites
This procedure assumes that:
•  You have a vacant interface port on your Processor Unit.
•  You are familiar with NMEA and other relevant datagram formats.
•  You know how to set up the parameters for serial and local area network (LAN) communication.
•  The interface port is set up with the correct communication parameters.
•  The ME70 system is turned on and operates normally.
•  The new sensor is physically connected to the ME70 system using a serial or network cable. The sensor is turned on and in normal operation.
Neither tools nor instruments are required.
Context
The motion reference unit (MRU) measures the roll and pitch movements of the vessel. The information provided by the motion sensor is used by the ME70 system to stabilize the beams.
Note
The input from the motion reference unit (MRU) is of vital importance to the ME70. An unserviceable - or inaccurate - sensor will render the scientific data useless. Due to the importance of the motion sensor data, the ME70 will stop "pinging"’ if the information from the sensor is lost.
The ME70 system supports the following datagram format from a motion sensor:
•  Teledyne TSS1
Teledyne TSS1 is a proprietary datagram format created by Teledyne TSS Navigation Systems for heave, roll and pitch compensation. When you select this protocol, the number of sensor variables is fixed, and there is no token associated with it.
•  Kongsberg EM Attitude 1000
The EM Attitude 1000 is a proprietary datagram format created by Kongsberg Maritime for use with digital motion sensors. It holds roll, pitch, heave and heading information. The datagram contains a 10-byte message. In many new designs, this datagram format has been replaced with EM Attitude 3000 format.
•  EM Attitude 3000
The Kongsberg EM Attitude 3000 is a proprietary datagram format created by Kongsberg Maritime for use with digital motion sensors. It holds roll, pitch, heave and heading information. The datagram contains a 10-byte message.
Procedure
1 Connect the motion sensor system to an available communication port on your computer.
This is described in the Installation Manual.
2 Open the Setup menu.
3 On the Setup menu, select Installation.
Image
Observe that the Installation dialog box opens. This dialog box contains a number of pages selected from the menu on the left side.
Note
If you want to use a serial line to interface the motion sensor, and no COM ports are available, you must first release a port on the I/O Setup page. If you choose a serial COM port to interface the motion sensor, make sure that you do not put the same COM port to other use on the I/O Setup page.
4 Release an unused serial port (COM) port.
a On the left side of the Installation dialog box, select I/O Setup.
b Observe that the available serial and network interface ports on the computer are listed.
c If you have a vacant COM port, select it, then select Remove to delete it from the list.
d At the bottom of the page, select Apply to save your settings.
e Close the Installation dialog box.
f Restart the ME70 system.
Restarting allows the Processor Unit to "free" the port.
g When the ME70 system has started, proceed to the Motion Reference Unit page to put the communication port to use.
5 On the left side of the Installation dialog box, select Motion Reference Unit.
6 Set up the interface.
a Select the Ethernet port or serial port you want to use.
b Select which protocol (datagram sentence) you want to use.
c If you are using a serial line, define the baud rate.
7 At the bottom of the dialog box, select Apply to save your settings.
8 Continue your work in the Installation dialog box, or select OK to close it.
Further requirements
You must insert the physical location of the motion reference unit related to the reference point (origin) you created on the Ship page. 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.