Sherwood Wisdom Anomaly

[ArizSig]

I spent last week diving on the liveaboard Don Jose in La Paz. After the 18th dive of the week my computer logged a "phantom" dive during a surface interval. The dive was logged as 19 minutes, 5 foot max depth, water temp 38 (yes - 38!).

I couldn't get anyone on the boat to admit to putting the computer in the ice chest, and I promise the water never got below the low 80's, I'm not sure what happened. The boat was moving between sites when the computer logged this dive.

It seemed to function fine in all aspects (except for the mystery dive) so I cautiously kept diving with it. It worked fine for the rest of the trip, no more strange log entries.

The computer did not get rinsed at the end of each day (the Don Jose is fairly primitive, no facilities to rinse gear except cameras). Could not rinsing it cause mystery dives?

I'm going to contact Sherwood and see what they say about it, but thought I'd ask the experienced minds here also.

 

[pdoege]

I have had my Cressi Archimede start to complain if its water detector gets confused during the surface interval.

Perhaps you left the unit in a puddle of water? I can see how the boat's movement and the water could fool the computer into thinking that it was under 5ft.

My Cressi only needs one "under 5ft" event every 10 minutes to run a dive.

I can also imagine that the presence of evaporating water could confuse the temp sensor.

I hang my computer and BT from my harness during the SI to avoid these problems.

Just a thought,
Peter

 

[ArizSig]

You may be onto something with the "only needs one 'under 5ft' event every 10 minutes". The Wisdom seems to start registering depth at 4 feet, and only needs to go below that once every 10 minutes to consider it a single dive.

The computer was clipped to the waist d-ring on my BC, which was still mounted on a tank. The waist d-ring would allow the computer to rest on the deck. I suppose water could puddle there.

The evaporation idea makes a lot of sense, the air temp was about 95 F so it would probably be a fairly rapid evaporation rate.

I'm curious if there have been any firmware revisions to this computer. Mine is rev 1a.