Marport’s multifunction XL-DD ‘Small Frame’ trawl door sensors have all the functionality of larger sensors

Designed to meet the needs of smaller trawlers towing semi-pelagic gear or flying their doors off the bottom, and using gear on which space is at a premium, Marport’s multi-function XL-DD ‘Smal Frame’ trawl door sensors have all the functionality of larger sensors, operating with a master and slave arrangement. The master sensor sends both sets of data to the catching vessel’s wheelhouse, with update rates of as fast as every three seconds, providing the skipper with door spread, inward/outward heel, forward/aft tilt, depth and temperature data.

The master and slave sensors communicate via a 110 or 144kHz wireless link, with the option of a 30,8kHz frequency used in special applications in gear and fisheries research.

MFX trawl door sensors are essential for keeping the gear correctly aligned, particularly working semi-pelagic or pelagic gear in which precision is critical to controlling the fishing gear and optimizing fishing opportunities, ensuring that the gear geometry is maintained and providing early warning if there is a problem with the trawl, which in turn allows skipper to compensate or haul and fix the problem without wasting time and fuel.

Battery life is typically around 90 hours, based on a standard charging time of 8 to 12 hours, although endurance can be extended by using power-saving settings.

Technical Specifications

Uplink Frequency 30 to 60 kHz
Uplink Beamwidth 70o
Range to Vessel 2500m
Depth Range 1600m
Pitch & Roll (Angle) ±90o
Pitch & Roll (Accuracy) 0.1o
Depth Resolution 0.1m with 0.1% accuracy
Update Rate Depth:3-8 sec

Temp:3-16 sec

Depth Range 300/600/1200/1800m
Temp Measurement Range -5oC to +25oC
Temp Accuracy ±0.1oC
Battery Type Lithium-Ion
Typical Battery Life Up to 100 hours Master
Charging Time Standard: 8-12 hours

Fast Charge: 4 hours

Weight in Air 5.0 kg
Weight in Water 0.9 kg
Warranty 2 years (Sensor & Battery)