AmiTrawl solutions

AmiTrawl is designed to monitor and control the trawl winches during all phases of trawling. It displays and monitors length, speed and tension for wires.

The system consists of a main PLC and a remote PLC. The remote PLC is located on the bridge. It collects signals from the push buttons and joysticks on the operator’s panel and sends control signals to the main PLC. The main PLC receives signals from the transmitters and the proximity switches connected to the winches. The data from the main PLC is displayed on a Panel View.

Length and speed are measured with proximity sensors attached to the winches. Measurements of the tension use the relationship between load in a wire and the natural frequency of vibration.

Functions of AmiTrawl


  • Wire tension (in tonnes) displayed in bar- and digital display.
  • Analogue wire speed display (in m/min or ft/min), with signs indicating the direction.
  • Wire length (in meter or feet) displayed in bar- and digital display.
  • Difference in length between the wires, displayed in bar- and digital display.
  • Trawl pressure with the ability to preset max/min pressure during trawling.
  • Pressure in the hydraulic system (in bar or psi).


  • Speed of the ship (in knot). (Requires a speed indicator interface).
  • Several data about the trawl’s position and movements in the water. (Requires interface to SCANMAR monitoring-equipment).


  • Shoot function; shoots the trawl
  • Heave function; heaves the trawl
  • Trawl function; activates the automatic compensation to maintain the shoot length.
  • Stop: stops the winches from shoot, heave or trawl state.
  • Compensate in: if the trawl is too far from the boat during trawling, the trawl will slowly heave until shoot length is attained again.
  • Compensate out; reduces the pressure during trawling if the trawl is too close to the boat.
  • In addition, there are signals to functions like start/stop pumps etc.


Alarms and warnings:

  • High/low tension.
  • High speed
  • High difference in length between the wires.
  • Warning during shooting: wire-length before shoot length is reached.
  • Warning during heaving: distance from boat to trawl-doors.
  • Warning during trawling: distance outside/inside shoot length.


  • Alarm for high oil-temperature. (Requires thermostat interface).

Control limits:

  • Shoot length: Set length value during trawling.
  • Compensating limit during trawling: Wire-length outside/inside shoot length.
  • Heave stop: Wire-length when the winches stop heaving.