Sea Tel 9711-92, Инструкция по установке и эксплуатации

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Installation Troubleshooting 9711-92 Ku-Band TXRX
17-4
17.3.2. Series 9711 Antenna Initialization
Turn the pedestal power supply ON. The brakes on the Elevation and Cross-Level motors will release. A brake
release power supply control circuit supplies 24 VDC to the brakes initially (5-10 seconds) and then reduces
the voltage to 12VDC. The PCU will initialize the stabilized portion of the mass to be level with the horizon
and at a prescribed Azimuth and Elevation angles in the specific sequence of steps listed below.
Initialization is completed in the following phases, each phase must complete properly for the antenna to
operate properly (post-initialization). Observe the Initialization of the antenna pedestal.
•
Step 1. Elevation and Cross-Level axes activate simultaneously - Input from the Elevation
sensor is used to drive the Elevation of the equipment frame to 45.0 degrees in elevation. Input
from the Cross-Level sensor is used to drive Cross-Level of the equipment frame to bring it to
level (this results in the tilt of the Cross-Level Beam being level).
•
Step 2. Azimuth axis activates - Antenna drives CW in azimuth until the “Home Flag” signal is
produced. This signal is produced by a home switch actuated by a cam on the azimuth driven
sprocket. After a short period of time (a total of approximately 1-2 Minutes after power is
initially applied to the antenna), the PCU will report its model setting and software version
number to the Antenna Control Unit (ACU).
This completes the phases of initialization. At this time REFLECTOR A (C-Band) will be at elevation 45.0
degrees and Relative azimuth will be at home flag (home switch actuated).
If any of these steps fail, or the ACU reports model "
xx11
", re-configure the PCU as described in the
Maintenance section of this manual. If initialization still fails, this indicates a drive or sensor problem.
17.3.3. Troubleshooting using DacRemP
While troubleshooting a Sea Tel 3-Axis Antenna System, you must classify the fault you are dealing with as a
failure within one of three major system functions: Targeting, Stabilization, and Tracking. Your system will
not operate properly if there is a failure with any one of these functions. A few simple checks may help
determine which fault (if any) that you are dealing with. The matrix below lists some test(s) and which of the
DacRemP graph selection would be best to use to identify a fault. The end of this chapter contains examples
on how to use DacRemP to diagnose a fault.
Targeting:
is the ability to accurately point the antenna to an angular position in free space and is
controlled by the ACU. (Does the system drive to the Azimuth, Elevation, and Polarity positions within 1
degree of the desired satellite?)
Stabilization:
is the process of de-coupling the ships motion from the antenna and is controlled by the
PCU. (Does the system maintain the satellite link after turning off TRACKING?)
Tracking: is the process of issuing fine adjustments to the pointing angle of the antenna to optimize the
received signal level and is controlled by the ACU. (Does the system pass a four quadrant-tracking test?)
Functional Test(s) DacRemP Graph
Selection to use
System Function(s)
Four Quadrant Tracking. ADMC (Position) Tracking
Azimuth Encoder Verification. ADMC (Position) Targeting
Sea Trial ADMC (Position) Targeting
Tracking
Stabilization
Side Lobe Plots ADMC (Position) Tracking
Targeting Alignment (AZ & EL Trims) ADMC (Position) Targeting
Determine Blockage Mapping ADMC (Position) Tracking
Unwrap recovery (Limited Az systems only) ADMC (Position) Stabilization
Pedestal Gain Verification DISPIVC (Loop Error) Stabilization