Simrad PI, Руководство по установке

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Simrad PI Catch monitoring system / Trawl hydrophone
8
851--164472 / Rev.B
Pre-installation check-list
Choosing the optimal locations for hydrophones is not always
easy, but decisions made at this phase of the installation process
are critical to future system performance. Determining the best
configuration for a given vessel often involves a compromise
between contradicting requirements.
To aid in this evaluation process Simrad recommends that this
installation manual be read thoroughly and the following check
list completed before deciding on a final installation strategy for
the PI system.
1 Hydrophones do not have a direct line-of-sight to the main
propeller and are placed where the vessel’s hull protects
them from underwater acoustic noise as well as possible.
2 Hydrophones must always have an unobstructed
line-of-sight to the sensors attached to the gear for the
system to operate properly.
3 The distance from the main propeller to the hydrophones
should be greater than ten meters. A separation of less
than ten meters can reduce system range significantly.
4 If thrusters are installed, hydrophones should be located at
least four meters from them.
5 Avoid locating hydrophones behind thrusters where air
bubbles from their tunnels generated when the vessel
pounds can block sensor signals.
6 Hydrophone should not be placed forward of other
underwater acoustic equipment and preferably behind it as
far away as possible, distances of less than one meter
should be avoided.
7 There should never be possible sources of underwater
acoustic noise placed in front of hydrophones.
8 Hydrophones should be offset twenty degrees from the
vessel’s centre line for normal single boat trawling. This
provides a ten degree overlap and a coverage area of
ninety degrees aft. Refer to the corresponding sections of
this manual for more information.
9 If there is any doubt about the best fore-and-aft location,
the port hydrophone can be placed a little farther aft (three
to five meters) in relation to the starboard. Hydrophones
can be tilted at slightly different angles when operating in
both deep and shallow waters. Refer to the corresponding
sections of this manual for more information.