• Advanced echo sounder showing fish influx and volume

  • Measures the height of the trawl opening, whether the trawl is on the bottom and the distance between the trawl and the bottom

  • Applications: Pelagic trawl, bottom trawl, Danish/Scottish Seine

  • Ideal together with DoorSensors for showing a simplified trawl geometry

Advanced Echo Sounder

The TrawlSounder is an advanced echo sounder showing the height of the trawl opening, if the trawl is on the seabed and the distance between the trawl and seabed.

It also provides a simplified “sonar” that shows whether there is fish influx and the volume. Choose between “classic view” or “density view” on your Bridge System. Wireless monitoring of the trawl opening and intermediate section of the trawl has become a matter of necessity in many of the world’s fisheries.

Mounted in the belly it shows whether the trawl height is stable, or if a bucket effect is arising and allowing fish to escape. It also shows the volume of fish passing through.
Together with a TrawlEye in the opening it is easy to see whether the fish seen entering the opening end up in the cod end.

Trawl Geometry

The TrawlSounder is ideal together with the Door-Sensors and the TrawlSpeed / Symmetry sensor to get full control of the trawl’s geometry.













Echo sounder

Trawl opening1,5 – 150 mFrequency96 kHz
Clearance1,5 – 150 mBeam width40 deg
Fish density0 – 9


Resolution0.1mIn air5,9 kg
Accuracy± 3 %In water1,9 kg



Update rate trawl opening appx. 11 secLength 246 mm
Update rate clearance appx. 8 secWidth224 mm
Update fish density appx. 8 secHeight104 mm
Operation timeappx. 20 hrs


Max depth1200 mStorage-20 til +55 °C


Waste treatment of sensorAccording to WEE-Directive.
The sensor should, however, be treated as hazardous waste when the NiCd battery is in place
TypeNiCd, 2x12 V / 600 mAh


Charging time1,5 hourCE

*Note: All specifications are subject to change without prior notice.
* Depends on acoustic conditions, ships noise, mounting and alignment of sensors and hydrophone.