Displaying Trawl Positioning from Scala2 on MaxSea Version 12

You can export trawl positioning data coming from Scala2 to MaxSea v12 application.

Before you begin

  • You must have a GPS and door positioning sensors.
  • Compatible MaxSea version: MaxSea version 12.
  • Compatible Scala version: 01.06.06 (only PTSAL sentence) / 01.06.14 and after.
  • Compatible Scala2 version: 02.00.02 and after.

About this task

You can export trawl positioning data from Scala2 to MaxSea with PTSAL or IIGLL sentences. With PTSAL sentence you can display the trawl on MaxSea from the positions of trawl wings and center between both doors. With IIGLL you can display the trawl only from the position of the center between both doors. You cannot display a 3D view of the trawl when using IIGLL sentence.

To use PTSAL sentence, you need a good stability of heading values. If heading values are unstable, the trawl displayed in MaxSea will have erratic movements. If this is your case, use IIGLL instead, as it is more stable for trawl positioning.

Note: Scala v.01.06.06 can only emit PTSAL sentence.

Procedure

  1. In Scala2, open the control panels and in trawl data, click Doors Positioning. Check that you receive door positioning data.
    Note: If you receive neither warp lengths nor slant distances, you can select Estimate horizontal distance from depths in Trawl Modeling > Doors Positioning System. You will get an estimation of the horizontal distance between the door sensors and the boat calculated from the depth of the sensors.
  2. To configure the export of trawl positioning data:
    1. Click Menu > Settings.
    2. Under the NMEA Outputs tab, click Add.
    3. In Port Settings, depending on your installation select Serial port or UDP port and enter a port. If using a serial port, enter a baud rate of 19200 for PTSAL and 4800 for IIGLL to correspond with baud rates in MaxSea.
    4. In Data to Emit, select Emit only selected data types and deselect all the items.
    5. Select Emit trawl positioning sentence and choose between $PTSAL or $IIGLL.
  3. To display the trawl when using PTSAL sentence, make sure that MaxSea receives heading data from Boat instruments. You can check from Data Display.
  4. To configure Trawl parameters:
    1. In Data Input/Output Settings, click the Trawl tab.
    2. Click Add instrument.
    3. Put the same port as configured on Scala2.
    4. Click Next.
    5. If using PTSAL sentence select PACHA/GEONET and if using IIGLL select Simrad ITI.
    6. You cannot change the baud rate from MaxSea. If using a serial port, make sure you put the same baud rate in Scala2.
    7. Click Finish.
  5. If using PTSAL sentence, click Boat > Advanced Settings and in System, select PACHA.
  6. Click the Data Display tab and check that you see:
    • For PTSAL sentence, 3 trawl positions with latitude and longitude data.
    • For IIGLL sentence, 1 trawl position with latitude and longitude data.
  7. To check incoming data:
    1. Click the Check Data tab.
    2. Select the port.
    3. Click Display.
      Figure 1. Example of incoming PTSAL sentence

Results

From MaxSea, you should see the trawl behind the boat.
With a PTSAL sentence, there are 3 points corresponding to the location of the 2 trawl wings and of the center between the doors. The 3 lines are the headings of the wings and doors.
With a IIGLL sentence, there is 1 point, corresponding to the center between the doors. The line corresponds to its heading.
Tip: If you need to test the NMEA connection but the sensors are not in water: configure the same output settings in ScalaReplay2, then replay SDS files containing positioning data.