o2 sensor

[PfcAJ]

Ok, Jim wants some more activity so I'll take a stab at it.

For you Rb folks, what kind of times are you doing on your units and do you experience cell errors after a certain time period?

I did a 3hr dive a few weeks ago on my RB80, and it was fitted with a single sensor. Toward the end of the dive (last 30mins or so) it read "1". Not 1.2, or 1.6, or .98, or even 1._ No,...Just "one". I could force fresh gas addition and make it read what it should have, but it was temporary.

I'd read many accounts of humidity being the x-factor with these things, but naturally I haven't experienced it myself. Looking for real life stories from the membership.

 

[GrimSleeper]

I'm new to CCR, but I dive in one of the most humid places on Earth and have had my fair share of O2 cell struggles...

Moisture usually causes cells to 'lag', so they'll respond slowly and often not reach peak output. In those circumstances, I'd expect flushing the loop to confirm that the cell is not responding properly, rather than make it read correctly. What you describe sounds to me like a more fundamental fault with the cell itself, or the electronics turning the voltage into a ppO2 reading.

 

[PfcAJ]

The monitor is one of these
https://gorilladiving.com/product-category/ppo2-monitor/g2-rs-ppo2-monitor/

Sensor is a maxtec 305.

 

[GrimSleeper]

Don't know anything about that monitor, and not enough of an engineer to come up with anything helpful.

On the plus side, you dive an RB80, don't you? At least you don't have to worry about it trying to tox you if the cell reads low… :/

 

[PfcAJ]

Ya, I'm pretty happy about that little feature

 

[LiteHedded]

deposit that piece of gear firmly in the trash.

 

[tstormdiver]

My Prism2 has 3 sensors. In the year & a half, I have had the unit, 2 sensors have gone bad (I did change all 3 out at 1 yr). One sensor was bad right out of the box, one went bad right at the year mark. Since, as I was training on it, it could be a month in between dives, so I would recalibrate the sensors nearly each time. I'm certain that didn't help the life span, but at such a long period between training sessions, felt it was necessary. After a long cold winter, things are starting to warm (relatively speaking) finally, so I will be using it.

 

[w ripley]

My cave dives are usually 3-5 hours (have done several in the 5-7 hour range). Always when I pull the head the sensors are just wet, dripping with water. It's not unusual for one of the sensors to go out (not die, but give strange readings) during these dives. I let them air dry that night and all work fine the next day.

I've never had more than one go out on a dive, unless it just expires which doesn't happen all that often. I replace all 3 at the start of each year, and pot-check at 2-3 ATMs on a regular basis.

Tyledynes worked fine when they were available, but even had one vary on long dives like mentioned above. Tried but don't use Maxtec anymore, as wasn't happy with their performance. Been using AIs for years with only the occasional glitch noted above.