COBHAM Sea Tel 9711-56 IMA C Band, Installation Manual

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Site Survey Sea Tel 9711-56 IMA
3-6
EAR Controlled - ECCN EAR99
millimeters in depth and 10 millimeters in thickness.
2. When possible, the antenna ADE pedestal column should align with a vertical truss support.
3. For every 100 kilograms of ADE weight over 250 kilograms, the depth of the platform
stiffeners should be increased by 50 millimeters and thickness by 2 millimeters.
Sea Tel does not have a recommended arrangement for a truss mast – the variability of truss mast
designs means that each installation needs to be evaluated separately.
3.6. Safe Access to the ADE
Safe access to the ADE should be provided. Provisions of the ship’s Safety Management System with regard
to men aloft should be reviewed and agreed with all personnel prior to the installation. Installations greater
than 3 meters above the deck (or where the access starts at a deck less than 1 meter in width) without cages
around the access ladder shall be provided with means to latch a safety harness to a fixed horizontal bar or
ring.
The access hatch for the ADE shall be oriented aft, or inboard, when practical. In any case, the orientation of
the ADE access hatch shall comply with the SMS guidelines onboard the ship. Nets and other safety rigging
under the ADE during servicing should be rigged to catch falling tools, components or fasteners.
3.7. Below Decks Equipment Location
The Antenna Control Unit, Terminal Mounting Strip and Base Modem Panel are all standard 19” rack mount,
therefore, preferred installation of these items is in such a rack. The ACU mounts from the front of the rack.
The Terminal Mounting Strip and Base Modem Panel mount on the rear of the rack.
The Satellite Modem, router, VIOP adapter(s), telephone equipment, fax machine, computers and any other
associated equipment should be properly mounted for shipboard use.
Plans to allow access to the rear of the ACU should be considered.
3.8. Cables
During the site survey, walk the path where the cables will be installed. Pay particular attention to how cables
will be installed; such as what obstacles they will be routed around, difficulties that will be encountered and
the overall length of the cables. The ADE should be installed using good electrical practice. Sea Tel
recommends referring to IEC 60092-352 for specific guidance in choosing cables and installing cables onboard
a ship. Within these guidelines, Sea Tel will provide some very general information regarding the electrical
installation.
In general, all cable shall be protected from chaffing and secured to a cableway. Cable runs on open deck or
down a mast shall be in metal conduit suitable for marine use. The conduit shall be blown through with dry air
prior to passing cable to ensure all debris has been cleared out of the conduit and again after passing the cable
to ensure no trapped moisture exists. The ends of the conduit shall be sealed with cable glands (preferred),
mastic or low VOC silicon sealant after the cables have been passed through.
Cables passing through bulkheads or decks shall be routed through approved weather tight glands.
3.8.1. ADE/BDE Coaxial Cables
The first concern with the coaxial cables installed between the ADE & BDE is length. This length is
used to determine the loss of the various possible coax, Heliax or fiber-optic cables that might be
used. You should always provide the lowest loss cables to provide the strongest signal level into the
satellite modem.
Be sure that the shield(s) of the coaxes are not in contact with the ships ground.
The coaxes must be of adequate conductor cross-sectional surface area for the length of the cable
run and that the loop resistance of the cable run is less than 2.0 ohms. Copper clad iron center
conductor cables should never be used.
Signal cable shall be continuous from the connection within the ADE radome, through the structure
of the ship to the BDE. Splices, adapters or dummy connections will degrade the signal level and are
discouraged.