Furuno Network Sounder DFF3 - Manual (Page 16)

1. MOUNTING
9
• A magnetic compass will be affected if the network sounder is placed too close to it. Observe
the compass safe distances noted in the safety instructions to prevent disturbance to the mag-
netic compass.
Fasten the network sounder to the mounting location with four self-tapping screws (5×20), refer-
ring to the outline drawing at the back of this manual for mounting dimensions.
1.3 Transducer
The performance of the echo sounder largely depends upon the transducer position. Select a
place least affected by air bubbles since turbulence blocks the sounding path. Further, select a
place least influenced by engine noise. It is known that air bubbles are fewest at the place where
the bow first falls and the next wave rises, at usual cruising speed.
Note: The face of the transducer must be facing the sea bottom in normal cruising trim of the boat.
1.4 Optional Speed/Temperature Sensors
ST-02MSB, ST-02PSB
1.4.1 Mounting considerations
Select a suitable mounting location considering the following points:
• Select a mid-boat flat position. The sensor does not have to be installed perfectly perpendicular.
However, the sensor must not be damaged in dry-docking operation.
• Select a place apart from equipment generating heat.
• Select a place in the forward direction viewing from the drain hole, to allow for circulation of cool-
ing water.
• Select a place free from vibration.
• Do not install near the transducer of an echo sounder, to prevent interference to the echo
sounder.
1.4.2 Mounting procedure
1. Dry dock the boat.
2. Make a hole of approx. 51 mm in diameter in the
mounting location.
3. Unfasten locknut and remove the sensor section.
4. Apply high-grade sealant to the flange of the sen-
sor.
5. Pass the sensor casing through the hole.
6. Face the notch on the sensor toward boat's bow
and tighten the flange.
7. Set the sensor section to the sensor casing and
tighten the locknut.
8. Launch the boat and check for water leakage
around the sensor.
Locknut
123
Face "notch"
toward bow.
Flange nut
Coat with
silicone sealant.
51
Brim
φ 77