Simrad ITI TRAWL SYSTEM - SERIAL DATA COMMUNICATION REV A Instruction Manual page 27

$PSIMMW,xxxx.x,M,xxxx.x,M,yyy.y,T,z.z,M,y.y,D,c,hhmmss*hh<cr><lf>
xxxx.x,M slant range in metres to middle weight (clump)
xxxx.x,M horizontal range in metres to middle weight
yyy.y,T true bearing (deg.rel.north) to middle weight
z.z,M signed deviation in metres (if deviation positive, then middle
y.y,D "starboard angle" between true GPS course (or heading if no
hhmmss time of transmission
857-164777 / A
- filtered values.
- unfiltered values
- nullfields if depth-sensor not activated (will calculate
horizontal range with manual set depth).
- requires gyro input for reliable data.
weight further out than door-door line)
- an offset to the deviation may be set in the trawl setup in order
to get the deviation near zero when the trawlgeometry isideal.
A positive offset will shorten the mid weight wire
- a mid weight filter, filtering the signed deviation, is found in
the trawl setup.
About the mid weight filter:
- the mw filter calculates from unfiltered horizontal ranges for
mw filter setting of 1 to 5 and if active depth sensor on trawl
- the mw filter calculates from filtered horizontal ranges for
mw filter setting of 6 to 10 and active depth sensor on trawl
- the mw filter calculates from filtered slant ranges if no active
depth sensor on trawl.
GPS) and the "Door-Door Line" of the trawl (0° < y.y < 180°).
c status of data, primarily middle weight deviation status
A: OK
B: OK but ambiguous
(± on deviation, presented range complies with positive
deviation, i.e. the larger range possibility)
C: Uncertain (angle based calculations)
D: Uncertain and ambiguous
E: Invalid data, required sensors not active
V: Invalid data, throw away
W: Invalid and ambiguous.
(time of Middle weight deviation calculations)
- requires ZDA input from GPS for accurate timestamP.
Instruction manual
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