Kongsberg Seatex Seapath 200, Installation Manual

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Seatex Seapath 200 Installation Manual, rev. 13 Installation
12
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The antenna baseline length is recommended in range 2.5 to 4.0 meters, but 1 to 5 meters
can be used. Maximum heading accuracy is achieved at 4.0 meters baseline.
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The maximum length for each of the antenna coaxial cables is 100 metres for the cable
type normally delivered with the system (1/2" Superflex). If longer cables are needed, a
low noise signal amplifier (LNA) should be fitted.
3.3.2 The MRU 5
For the MRU 5, consider the following:
•
The unit is designed for installation in an indoor environment and for operation within its
temperature range.
•
The unit is to be mounted close to the user equipment of which it is supposed to measure
the motion. This is to avoid errors in alignment with the user equipment and to eliminate
errors due to ship hull torsion.
•
If the system is not allocated to measure motion of a particular user equipment, mount the
MRU as close to the ship's centre of gravity (CG) as possible. This to ensure best roll and
pitch measurements. If it is not possible to mount the MRU close to CG, try to mount it
along the longitudinal axis of the ship and as close to the CG as possible. Avoid mounting
the MRU high up or out to the side of the ship.
Be aware of:
•
Vibrations
. Direct mounting onto the main hull structure is preferable.
Note
The worst mounting positions are thin walls that may come in resonance with
vibrations driven by machinery, propellers, pumps or motors. Avoid mounting the
MRU close to hydraulic pumps and valves where there are high frequency
vibrations.
•
Temperature changes
. For safe mounting of the MRU, place the unit in a location where
the temperature is low and where changes in temperature are slow. A location directly on
the hull far away from the heat of the machinery, heaters and air conditioning systems is
preferable.
•
Corrosion problems
. Place the MRU in a location where no direct splashing seawater is
present.