Raymarine Tri-data depth failure

[lumphammer]

My depth reading on the ST60+ control head has just gone to --- (three dashes), two days ago it was working the transducer is mounted internally and is still immersed in water, connections to the back of the control head are good. The speed reading is OK.

Is there any way with a DVM that I can find out if it is the transducer or the control head that is faulty?

 

[nimbusgb]

Listen to it.

No seriously, get everything quiet and get close, say within a foot or so, to the transducer and listen for a regular clicking. Alternatively get a 10 year old in the same cabin as the transducer.

! DO NOT PUT YOUR EAR TO THE UNIT !

The transducer should be firing through oil rather than water, water evaporates! Cooking oil, olive oil, engine oil I've used 'em all.

Did I mention ! DO NOT PUT YOUR EAR TO THE UNIT !

You can sometimes pull the transducer and put it into a glass of water, you may see regular pulses of ripples set up.

 

[Spirit of Glenans]

In my first boat, a Leisure 17, I mounted the transducer for a fishfinder in a tube glassed to the floor and filled with castor oil. It worked!

 

[nigelmercier]

If you don't get any luck from Raymarine, try these guys: http://www.airmartechnology.com/marine-product-search.asp?q=St60

 

[lumphammer]

Thanks for the responses. It is clicking and I can still hear so I assume that I didn't put it to my ear.

The strange thing is I get a reading by hanging the transducer directly in the sea, but not in its mounting in the mounting in the boat, although it has been reading normally with water as the contact medium for the last 5 years. I don't have a problem with evaporation as it is in a sealed pipe.

Would using oil make a difference? I don't really want to try if not as I just end up with an oily transducer rather than just a wet one.

My boat was copper coated last year and I sort of wondered if that could affect the trough hull reading although why it has waited 1 year to take effect I don't know?


Any thoughts gratefully recieved

PS I have tried with a new borrowed transducer and this does the same.

PPS Have also tried with rapeseed oil (all we had in the galley) with no change

 

[Billjratt]

Are you sure you're not trapping a bubble under the transducer face? Putting a little oil in the tube and forcing the transducer down against the inner hull face should work.

 

[Andrew G]

I've always masked the transducer before painting A/F but it shouldn't cause your problem.
I've had "---" twice, once as I crossed into more than 150m depth (scared me for a while at first - at 02:00 when I hadn't slept for 2+ days) the second when I put a screw through the cable. The temperature still worked fine - the screw had only gone through the one conductor.

I'd suggest rechecking the condition of the cable and the connectors at the back of the unit (they should be OK as youv'e had them off and on). I beleive that the cable is "tuned" to the unit and should not be shortened significantly (OK to re-terminate it).
Good luck, Andrew