Sea Tel 6012-12w, Руководство по установке

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6012-12W Installation Manual Site Survey
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.
2.8.1. 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.
Be careful of sharp bends that kink and damage the cable. Use a proper tubing bender for Heliax
bends.
Penetrations in watertight bulkheads are very expensive, single cable, welded penetrations that
must be pressure tested.
Always use good quality connectors that are designed to fit properly on the cables you are using.
Poor quality connectors have higher loss, can allow noise into the cable, are easily damaged or fail
prematurely.
In as much as is possible, don’t lay the coaxes on power cables. Don’t lay the coaxes on, or directly
beside, the cables from a second Sea Tel antenna, Inmarsat antenna and/or GPS antenna that are
also passing L-band frequencies. Don’t lay the coaxes on, or directly beside, radar cables that may
inject pulse repetition noise –as error bits - into your cables.
2.8.2. Antenna Power Cable
Be cautious of length of the run, for voltage loss issues, and assure that the gauge of the wires is
adequate for the current that is expected to be drawn (plus margin). Antenna power is
recommended (but not required) to be from a UPS, generally the same one that supplies power
to the below decks equipment.
Power cables shall comply with the provisions of IEC 60092-350 and -351 as practical. Power cables
may be routed through the same conduit as the signal cable from the junction box to the base of
the ADE. Power cables shall pass through separate radome penetrations from the signal cable.
The power cable shall be continuous from the UPS (or closest circuit breaker) to the ADE
connections within the radome. The power circuits shall be arranged so that ‘active,’ ‘common’ and
‘neutral’ (ground) legs are all made or broken simultaneously. All circuit legs shall be carried in the
same cable jacket.
2.8.3. Air Conditioner Power Cable
If your system includes a marine air conditioner (available with the 81 inch radome ONLY), run an AC
power cable to it from a breaker, preferably from a different phase of the electrical system than
supplies power to the ADE & BDE. Be EXTREMELY cautious of length of the run for voltage loss and
gauge of the wires for the current that is expected to be drawn.
Power cable shall comply with the provisions of IEC 60092-350 and -351 in so far as practical. Power
cables may be routed through the same conduit as the signal cable from the junction box to the base of
the ADE. Power cables shall pass through separate radome penetrations from the signal cable.
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EAR Controlled - ECCN EAR99