Airmar dst800 no stw or temp, but depth is working

davethedog

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Hello all,

Last few months the STW and temp from the airmar dst800 (via raymarine itc5) have not been displayed. The depth is still working however.

I have checked all the wiring connections and all seem fine (as said it was all working before). Am I correct in assuming this is likely a replacement with a dst810 being the likely solution if I want STW and true wind?

Is there a way to use SOG (via GPS reading on network, which works fine) for true wind at all?

Thanks
 

Pye_End

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Does your display give you 'ground wind'? Raymarine (at least on the i70) split up their 'true winds' into 2 - ie. taking into account boat movement (ie wrt the sea), and the other wrt the ground. Ground wind, afaik, uses GPS movement in it's calculation.
 

davethedog

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Does your display give you 'ground wind'? Raymarine (at least on the i70) split up their 'true winds' into 2 - ie. taking into account boat movement (ie wrt the sea), and the other wrt the ground. Ground wind, afaik, uses GPS movement in it's calculation.
Yes can get that displayed but not sure if as relevant as true wind ?
 

vas

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fwiw, my DST800 (nmea2000 variant) stopped displaying temp - or rather started displaying temp erratically, then stopped completely after the third year.
Since boat is on the water all year, it will only (dry I guess and) work for the couple of weeks on the hard every other year and the first day after being placed back in the water. So my guess is some form of water ingress on the temp thyristor that doesnt affect depth.
Speedwheel could be blocked, assume you have checked and cleaned it.
so easy albeit expensive solution is to replace with another airmar and avoid having to remove skinfitting and replace with other that should be similar or larger in dia!
Since I mainly want depth from it, I cannot justify the 300euro or whatnot, so staying with the half broken one.

V
 

davethedog

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fwiw, my DST800 (nmea2000 variant) stopped displaying temp - or rather started displaying temp erratically, then stopped completely after the third year.
Since boat is on the water all year, it will only (dry I guess and) work for the couple of weeks on the hard every other year and the first day after being placed back in the water. So my guess is some form of water ingress on the temp thyristor that doesnt affect depth.
Speedwheel could be blocked, assume you have checked and cleaned it.
so easy albeit expensive solution is to replace with another airmar and avoid having to remove skinfitting and replace with other that should be similar or larger in dia!
Since I mainly want depth from it, I cannot justify the 300euro or whatnot, so staying with the half broken one.

V
Think you may be correct regarding the failure, but annoyingly it was working before and when we sailed across the Atlantic in December we used the true wind a lot for the steer to wind as downwind sailing.

The speedwheel is spinning freely but no speed display or temp, as well as the log reading not showing on the MFDs.

When I use the MFDs to choose data sources, for depth it will find the ITC5, but for speed it will not even find the ITC5 (both connected to the same ITC5 and the same transducer)..strange
 

BabaYaga

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This may have no bearing on the OPs problem, but after reading post #13, thought I should mention it FWIW:

A couple of years ago I installed an itc5 to connect two very old (mid 90's) transducers for depth and speed/temp to a new STng network including an i70s. The depth worked right away, speed/temp did not.
Eventually, it turned out the culprit was that the thermistor was shot. Apparently, the ict5 uses the thermistor to identify the speed transducer. Without a thermistor signal, it would not see the speed transducer.
The solution was to put a resistor between two of the spades inside the ict5 that take the temperature signal (this fix is described somewhere on Raymarine's support site).
With the resistor in place, the speed data was read by the i70s and I have a constant temperature reading of some 8 degrees C, which relates to the value of the resistor chosen.
However, if the situation is similar with a combined transducer such as the dst800 I don't know.
 

vas

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interesting BabaYaga, I'm pretty sure that this doesnt apply to DST800, as temp on mine has failed now for almost 3yrs, but whenever I bother to clean the wheel, I do get a couple of weeks of STW readings before blocking again...
 

davethedog

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The other odd thing is, I do not have the log distance displayed anymore.. Not even stuck at a number as if the wheel was stuck.
 

vas

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The other odd thing is, I do not have the log distance displayed anymore.. Not even stuck at a number as if the wheel was stuck.
possibly because there's no stw sentence/PGN broadcasted in the system. Bet if you fix/replace the sensor it will automagically appear again.
 
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