Unit installation

FS70 Trawl Sonar System
6 974-24007001/4.1
1.9 Catch Sensors
The catch sensor “eggs” are wireless sensors mounted on the cod-
end of the trawl net to detect the stretch of the net as it fills up with
the catch. When sufficient stretch of the net occurs, the catch sensor
is triggered and sends an acoustic signal to the trawl sonar through
the catch receiver. The information is then sent to the processor and
displayed on the monitor.
The sensors have a rugged construction in order to withstand the
strain from winches and the power block. The operator can use up
to six sensors (with the 40 kHz system) simultaneously. The catch
sensors are equipped with rechargeable batteries.
1.10 PI Sensors Option
The FS 70 provides full integration with the PI System sensors.
Door Spread, Net Geometry, Bottom Contact, Rip Sensor and Cod
End Depth Sensors available from Simrad AS, Horten Norway.
1.11 Depth, Temperature & Sensors NMEA Output
The FS 70 Processing Unit can be configured to output NMEA data
information. The integrated sensor module will output Depth,
Temperature and PI Sensors data when interfaced to echo sounders
or other onboard equipments. The head rope depth information
appears on the sounder showing the location of the trawl in relation
to the fish or bottom returns.
1.12 Trawl Cable, Winch and Block
The trawl cable and the associated equipment are supplied by the
vessel. The trawl cable is chosen for maximum mechanical strength,
durability and minimum attenuation of the signals. Cables in
common use are coaxial with breaking points of 1500kg and
6000kg.