Edgetech 2000-CSS, User Manual

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6-6 6.0: TROUBLESHOOTING
2000-CSS COMBINED SONAR 0017423_REV_C
The main objective is to get the basic system working. It is therefore good practice to disengage any option
circuit cards installed in the unit and optional external system components at this time to reduce the
number of possible trouble sources.
6.3.1 Equipment Required
Except for the topside computer/power unit, only common laboratory test equipment and tools are
required for field troubleshooting. No special equipment is necessary. Typical test equipment includes:
•
Digital multi-meter, Fluke, or equivalent
•
Oscilloscope
•
Hi-pot tester
•
Capacitance meter
6.3.2 Transmission Verification
The 2000-CSS Towfish is different conventional side scan sonars used for many years. The early sonars
were driven with a high-powered energy burst similar to hitting a bell with a hammer. The transducers
are driven with a smooth rising lower power signal that matches the transducer response. Because of this,
there is no pronounced clicking noise emanating from the transducers when they are firing. Therefore,
the ‘listen for the clicking noise’ test cannot be used to verify sonar transmission during bench or on-deck
testing.
Sniffing with an oscilloscope can be used as a substitute to check transducer firing. One way is to attach
the scope probe’s ground to the towfish body and hold the open probe next to the transducer under test.
Set to about 20 to 50mV /Div.
A second method is to connect a several-turn wire loop across the scope probe and move it over the
transducer face. Electrical pickup should be noticed on the scope screen at each transmission burst.
Remember that the transducers and elements within the transducer may be firing together or in
sequence. One must make sure that the electrical pickup is not from an adjacent string.
6.3.3 Sonar Processor and Data Link
It is assumed that the sonar processor is up and working in order to complete system test and
troubleshooting. Refer to the sonar processor’s manual for its troubleshooting and diagnostic
information.
The other thing is that the high-speed data must be up and running so that the topside and sub-sea units
are communicating with each other. If the towfish boots up correctly and passes its internal self-test,