pro plus 2 temperature readings

[lungs]

Hi guys i just bought two pro plus 2 dive comp. 1 for me and the other one for my wife and i just noticed that their temperature readings are off by 10 degrees ....what can i do to fix this problem.....everything else works perfect........


Thank You......

 

[moinaman]

I too had this problem. After contacting Oceanic, I was informed that the temperature readings are that of the ambient air within the computer itself as the device does not have an external thermometer. Therefore, the Pro Plus II will not be able to achieve accurate water temp. readings during your dive profile. The device would have to remain at the same depth until such time as that the ambient air inside reaches the same temp. as the surrounding water. Most likely 15 minutes or more. This was a major disappointment for me as it basically renders the temp. readings useless.

 

[Teamcasa]

I don't know about that. I have two and they are both about 2 (on the plus side) deg different from most everybody else's computers.

I"d contact Oceanic and have them recalibrate it.

 

[DiveNav]

....... I was informed that the temperature readings are that of the ambient air within the computer itself as the device does not have an external thermometer......

Actually .... in most dive computers the temperature sensor is integrated with the pressure sensor. The pressure sensor is then integrated with the case of the dive computer to allow contact with the water .... so the temperature sensor has an indirect contact with the water.

There are however few factors that influence the temperature reading.
1) sensor calibration - this is done at the factory using automated procedures
2) self-heating. The electronic devices inside the dive computer (mainly the processor and the power regulator) generate heat that need to dissipate out. The influence of this internally generated heat on the temperature sensor is a function of where the sensor is located in the dive computer thermal resistivity equation (farther from the heat source and better is).
3) thermal inertia. When you start at the surface the dive computer could be substantially warmer then the water temperature (specially if You leave it in the sun while gearing up) and, once in the water, it could take some time for the extra heat to dissipate. The same concept applies when you ascend to the surface from a cold dive. Bigger the computer is and bigger the thermal inertia will be.

Alberto (aka eDiver)

 

[moinaman]

well, I will contact Oceanic again to see if they say anything different, however it was an Oceanic technician that informed me of this "flaw" with the Pro Plus II, that it does NOT have an external thermometer and relies solely on the temp. of the ambient air within the computer and confirmed my suspicion that it takes about 15 minutes at the same temp. to read correctly. Since I rarely stay at the same depth that long every temp. reading taken along my dive profile is inaccurate.

 

[SeaSoulSelf]

I have the same problem -- my temp readings show about 10 ° lower than my husband's PP2. The first time I had the problem, I sent the computer in to Oceanic and they replaced it a couple of years ago.

Now I have the same problem again, and a new one -- the year is not being retained or is being changed to a strange year (like 2026) when I upload into Oceanlog.

I don't sweat the temperature reading all that much, but it makes me think -- if the temp reading is off, what ELSE is off? Will be sending mine in again.