Kongsberg Simrad SN90 Reference Manual page 273

5 Inspect and clean the Transceiver Unit.
6 Inspect the Hull Unit. (if applicable)
A hull unit may be provided as an option. It allows you to lower and hoist the
transducer. All information and tasks related to the hull unit may be disregarded
and omitted if the SN90 system is installed without this unit.
Actions to be taken during dry docking
When the vessel is in dry dock you must take the opportunity to inspect and clean the
transducer.
1 Do a visual inspection of the transducer.
2 Clean the transducer and remove marine growth.
If necessary, apply anti-fouling paint as described in the dedicated procedure.
3 Make sure that all surfaces under the hull are protected with a high quality coating.
4 If relevant: Make sure that the inside of the installation trunk is also protected
with coating.
5 Inspect the physical conditions of the sacrificial anodes. Check for damage and
corrosion. If necessary, replace the sacrificial anodes with new anodes of the same
(or similar) type.
Actions to be taken whenever required
The hull unit was lubricated as a part of the production process. It was thus provided
fully lubricated when delivered to the vessel. Additional lubrication of the hull unit must
only take place when required.
Note
A hull unit may be provided as an option. It allows you to lower and hoist the transducer.
All information and tasks related to the hull unit may be disregarded and omitted if the
SN90 system is installed without this unit.
1 Make sure that the hoisting spindle is properly lubricated. Lubricate if required.
2 Inspect the hull unit for water intrusion.
3 If necessary, add grease to the transducer shaft sleeve.
381294/E
Maintenance procedures
271