Sea Tel Base Exit, Quick Start Manual

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Procedure, Field Replacement, Level Cage Kit, Base Exit
Page 4 of 9
Document No
135266 Rev B
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Tel, Inc.. This document may not be reproduced or distributed in any form without prior written
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10. Diagnostics:
Any incorrect readings from the above tests would relate to an error in the antennas control loop causing the system to
not stabilize correctly. The most likely cause of this is a defective sensor in the level cage. The next step will be to replace
the level cage and repeat the test which the antenna failed to verify if the system is now functioning correctly.
Should the problem persist other possibilities are a bad connection on the reference harness between the level cage and
PCU corrupting the feedback, or possibly the PCU itself not calculating the feedback correctly. However as the level cage
is the most likely component to be causing this issue replacing it is the first step in the troubleshooting procedure.
Once the problem has been rectified its good practice to refit the original level cage and see if the fault returns. It’s
possible that there was corrosion on the pins of the reference harness and by connecting the replacement level cage the
pins have been cleaned, allowing good metal to metal contact and giving the impression that replacing the level cage
rectified the fault (cleaning the pins on the PCU end of the reference harness is also advisable).
11. Further Information:
Should the system fail to target the correct elevation (physically pointing at a different position to the reading on the
DAC) or have issues driving past a certain elevation position then the most likely cause is a defective level cage motor.
If the system is displaying a pedestal error (error 8) then there is a drive issue with the antenna and attention will need to
be paid to the motor and motor driver (servo amp) for the relevant axis. A defective level cage won’t flag an error 8 as the
PCU doesn’t know if the feedback from the level cage is corrupt which is why the antenna will mispoint if the level cage is
defective.
Another potential issue which could cause the antenna to lose the satellite is if the vessels gyro compass is drifting,
accumulating error which is then fed into the control loop. This can be verified by running a DacRemP log file at sea to
monitor the pedestals readings when the AGC drops, or by putting the system into satellite reference mode to bypass
the gyro from the azimuth control loop.
12. 2406 Level Cage Configuration:
To use the level cage (part number: 122937 ‐ 1) on the 2406 pedestal, it will need to be converted into a 122937 ‐ 2. This is
done simply by re configuring the end stops on the back of the level cage assembly as per the below image. The standard
122937 ‐ 1 level cages has the end stops on the left ‐ hand side, these will need to be moved to the right ‐ hand side to use
the level cages on the 2406 pedestal.
122937 ‐ 1 122937 ‐ 2