Operation Manual

Simrad PI54

222

850-165186 / Rev.B

Note: In order to retrieve speed information, the relevant equipment

(GPS) must be interfaced to your PI54.

When you read the speed information from a GPS, the

information is very accurate. Due to the fact that the trawl

calculations are made continuously, even the slightest change in

speed will be reflected on the display presentation, and you may

experience that the markers fluctuate. If this is a problem, enter

the average vessel speed manually.

Trawl depth: Select Manual to enter average trawl depth. If

you run a pelagic trawl, you must use this setting. Select

Bottom if you run a bottom trawl, and you expect the trawl

depth to be equal to the depth measured by the echo sounder.

Note that in order to update the calculator automatically, the

echo sounder must be operational providing valid depth data.

These are shown with grey characters.

Wire length: Enter the length of the trawl wire. In most cases,

this is the length from the stern of the vessel to the trawl doors.

Wire length offset: Enter the distance from the trawl doors to

the headrope. This is normally a fixed value. The calculator will

add the wire length to the wire length offset, and use the sum of

these in the calculations.

Calculated marker delay: When in Auto mode, the delay is

shown in minutes and seconds.