Simrad PI32 SENSOR - MOUNTING Instructions

PI32 Sensor mounting instructions
PI32 Monitoring system for trawls and purses
The system below is configured for use with trawls and purse seines. It may
also be employed with Danish purses, pelagic trawls or other types of gear that
require depth, temperature, bottom contact and catch monitoring.
Depth sensor
Bottom sensor
Configuration - of sensors attached to towed gear should be toward the mother
vessel. Coverage is optimized when the tops of the sensors are oriented toward
the hydrophone mounted on the vessel's hull.
Catch sensor - will normally change status until the quantity of fish caught
is reasonably large. Once the cod-end fills, its natural tendendcy to become "pear
shaped" may cause the catch sensor furthest aft to tilt downwards temporarily
losing or generating unstable communication. This phenomenon is often
experienced just before the next proceeding catch sensor is activated.
Mounting - and protection of sensors is very important. Sensors attached to
head- or footropes are best protected when sewn in bags designed for that
purpose. Sensors attached to trawling gear should be firmly secured at their
forward ends and drawn aft so that they lay horizontally when towed. Sensors
attached to towed purse seining gear should be allowed to hang as freely as
possible and point vertically when pursing.
Depth sensor
Temperature sensor
Catch sensors
Purse seine
Bottom sensors - are attached to the purse wire using a
purse ring, wire strop and two karabiners. A weight of
Strop approximately 4.5 kg (or another purse ring) is attached
Purse
to the sensors' detector wire with a flexible, thin rope. The
ring
Karabiner
total length of the strop, sensor, detector wire and rope
determined the distance monitored to the bottom.
Shooting - thread the weight on the ring needle (but not
around the purse wire) so that the bottom sensor will
be deployed first. The weight must hang freely and sink
clear of other gear so that it may activate the sensor when
Detector
bottom contact is made.
wire
Monitoring- sensors are preferably attached to the purse
Rope
wire with a purse ring or alternatively, as show here, to
Weight the bridle. Sensors must be allowed to hang as freely as
possible so that they point vertically when pursing.
Sensors can be attached to the headwire to warn if it
is pulled under the surface when pursing. is pulled under the surface when pursing.
D3
D1
D2
Complete overview - of the fishing operation is achieved with three sensors
marked correspondingly with D1, D2 or D3 and attached to the purse seine as
illustrated. Make sure that the attachment locations chosen will not subject the
sensor to unnecessary abuse when shooting. Precautions should also be taken
when sensors pass through the powerblock.
Tuna purse - attach sen-
sors to the footwire, refer
to the Instruction manual
for details.