Raymarine ST60 tridata and water temperature

[gasdave]

I was trying to re-calibrate the water temperature on my Tridata last weekend (it was telling me the Clyde was a balmy 41 degrees!). A separate temperature check with another thermometer read 12.1 degrees which I thought a bit more realistic. Using the procedure described in the manual it wouldn't let me adjust the reading below 31.3 degrees (all units Celsius).

I can't understand why this should be. Anyone got any ideas or previous experience of this?

(I haven't asked Raymarine yet but will be)

 

[Robin]

I was trying to re-calibrate the water temperature on my Tridata last weekend (it was telling me the Clyde was a balmy 41 degrees!). A separate temperature check with another thermometer read 12.1 degrees which I thought a bit more realistic. Using the procedure described in the manual it wouldn't let me adjust the reading below 31.3 degrees (all units Celsius).

I can't understand why this should be. Anyone got any ideas or previous experience of this?

(I haven't asked Raymarine yet but will be)

Our Garmin triducer was reading 95(F in our case) until we realised the transducer had not been replaced in the hole affter painting it with antifoul and asstill propped up in the bilge for the paint to dry.:ambivalence: It explained why the depth wasn't reading at least.

 

[gasdave]

Transducer is definitely fitted correctly and reads correct depth, checked with a lead line. Although it is overpainted with some antifoul I wouldn't have thought this ought to affect temperature readings that much.

My puzzlement is more about why the instrument won't seem to allow calibration adjustment to less than 31 degrees C.

 

[RichardS]

Transducer is definitely fitted correctly and reads correct depth, checked with a lead line. Although it is overpainted with some antifoul I wouldn't have thought this ought to affect temperature readings that much.

My puzzlement is more about why the instrument won't seem to allow calibration adjustment to less than 31 degrees C.

32 degrees F is freezing point so a boat thermo might not go below that. Perhaps the display units are busted?

Richard

 

[earlybird]

Testing the temp. display is explained in Raymarine FAQ's. Disconnect the brown and white transducer wires and put a 10k resistor across the terminals. The reading should be ~77 deg F. (25 deg. C.). Other resistances give different temp. readings.
If this is OK, then the thermistor in the transducer is probably faulty. My Tridata has a resistor because the thermistor has failed o/c, making the instrument otherwise default to slave mode.
This makes the Clyde tropical!

 

[gasdave]

Testing the temp. display is explained in Raymarine FAQ's. Disconnect the brown and white transducer wires and put a 10k resistor across the terminals. The reading should be ~77 deg F. (25 deg. C.). Other resistances give different temp. readings.
If this is OK, then the thermistor in the transducer is probably faulty. My Tridata has a resistor because the thermistor has failed o/c, making the instrument otherwise default to slave mode.
This makes the Clyde tropical!

This is in essence what Raymarine support have suggested doing as a test - also questioning whether or not the transducer itself may be at fault. However does the actual calibration ability and range of the Tridata depend on the temperature measured by the transducer (whether correct or not)? It wouldn't allow me to set a temperature less than 31.3. I would have thought that function would be in the software or whatever, not coming from the transducer?
Units were definitely re-set to Celsius - I had just done that. It was previously reading 101F! Otherwise I'd be expecting to see pineapples and coconuts growing on Aran!

 

[earlybird]

I think that you first need to do the Raymarine test on the instrument. If that reads as expected then the transducer thermistor is probably faulty, as mine became, but in your case, low resistance.
The calibration offset range is presumably to cater for production tolerances in thermistor resistance etc. not major variations due to faults.

 

[Simondjuk]

As has already been said, the thermistor in the transducer has failed. It's incredibly common and not worth repacing it over as how long it takes to happen on a new unit seems to vary between several years and a few days.