Thanks!

I appreciate that! Thanks!

Thanks, will do!

Next Scuba 101 will be about trimix

Thanks!

Glad you enjoyed it!

Glad you enjoyed it!

There is a lot of promise in the solid state O2 sensors, but they are far from mainstream yet, not to mention they are over $1K each.

I don't know that much about them, but from what I have heard, they are going to be the better way to go once the price comes down a little.

I'm not an instructor. LOL. I'm just saying how I do it.

Here is a good article about them: gue.com/blog/what-ever-happened-to-solid-state-sensors/

As a general rule, if a sensor is weak enough that you can't use it in a rebreather, you shouldn't use it for an analyzer.

Earlier than that actually.

Correct, the device can't function without oxygen.

gue.com/blog/what-ever-happened-to-solid-state-sensors/

People still manage to die.

@@BlueWorldplus Almost every diver death I read about is someone using a rebreather that malfunctioned or was incorrectly assembled; equipment is rarely the cause of open circuit scuba fatalities.

If they get wet, they do not work. That is one of the challenges of rebreather design--making sure that the O2 sensors stay dry.

Computers are set to calibrate at pure O2 only.

@@BlueWorldplus thinking about it, it seems reasonable. Otherwise there would be an additional possible failure point if one doesn't exactly know the oxygen in the gas mix. I.e. if its 32,3 instead of 34%.

The problem is that solid state oxygen sensors requiers change in construction of the head of rebreather, also as for now poseidon is testing this but this is propioritary technology of this manufacturer so other producents would have basicly to buy this technology from them or invest a lot of money in developing similar system of their own

There is no question that the solid state ones are the future. I don't know much about them, but how do they handle extremely humid environments?

@@BlueWorldplus GUE published an article about the subject on their blog back in 2021, you can find it by googling "What Happened to Solid State Oxygen Sensors?". The essence was, that it is possible but still requires a lot of research and development to make them work reliably and accurate in the environmental conditions inside a rebreather. That's how I came to the conclusion that we still don't see solid state sensors in most rebreathers because manufacturers don't like to spend money on research and development.

The main issue is that those sensors requier external power to run (not like galvanic sensors that are basicly batteries) so you have to change build of whole electronics in head, as far as the problems with those sensors - I havent`t found any informations about problems only that they work great for long period of time (some were tested for much longer than 5 years without any problems) The second may be the cost of investment in those sensors (they are quite pricy but this is neglegble comparing to switching normal sensors for couple of years)

@@robit024 I would have expected they'd digitize sensor readouts in the head electronics in order to transfer them via CAN bus or some similarly reliable digital protocol to the controllers. Your description implies that they run the analog sensor voltage through the cable and even a plugged connection and then do the AD conversion in the controllers. Is that really true? Doesn't sound like a smart idea to me...