Measure scrubber runtime?

[Big-swede]

Thanks for all the inputs.

I'm not looking to push my scrubber limits, I almost never do dives longer then 2 hours and my manufacturer recommends 3h in cold water.

I'm just interested in different peoples approach to it.

I love how GUE have "scientific" answers to almost everything

From the people I have talked to and what I have read there seem to be three different approaches.

1. People like me who stay within the manufacturers recommendations.
2. People who have realized that those recommendations are most likely absolute worst case scenarios and from experience in groups we can "safely" push it another hour.
3.people who know themselves to well for their own good. "I know I guy that did 4h on this and his sac is **** compared to mine so I'll do 7 hours"

With some exaggerations

 

[Wibble]

Often wondered why there is no temperature sensor on the JJ. Obviously this tech won't work with a radial scrubber, but it will with an axial configuration, as demonstrated by the AP Inspiration and Revo.

My point about the Revo is that it's pretty much a binary measurement when the second scrubber begins to be used and warms up. This gives an absolute reading that half of the scrubber has been used (actually slightly more as it's measuring the second scrubber, but round it to half). This means that the measurements can be very accurately gauged. A bonus is that provided the second scrubber's not been used, it can be swapped over with another, so only needs 1.35kg/4lb of lime for a fill.

 

[Big-swede]

Often wondered why there is no temperature sensor on the JJ. Obviously this tech won't work with a radial scrubber, but it will with an axial configuration, as demonstrated by the AP Inspiration and Revo.

My point about the Revo is that it's pretty much a binary measurement when the second scrubber begins to be used and warms up. This gives an absolute reading that half of the scrubber has been used (actually slightly more as it's measuring the second scrubber, but round it to half). This means that the measurements can be very accurately gauged. A bonus is that provided the second scrubber's not been used, it can be swapped over with another, so only needs 1.35kg/4lb of lime for a fill.

You can apply the same technique to a normal axial scrubber, just add a mesh filter in the middle of the scrubber with temp stick on the outgoing side.

 

[rjack321]

Often wondered why there is no temperature sensor on the JJ. Obviously this tech won't work with a radial scrubber, but it will with an axial configuration, as demonstrated by the AP Inspiration and Revo.

The same reason there is no temp stick in a Meg, Kiss, Triton, Optima, SF2, Hollis, RB80, and others. It's an unneeded complication.

 

[Divermikey]

Often wondered why there is no temperature sensor on the JJ. Obviously this tech won't work with a radial scrubber, but it will with an axial configuration, as demonstrated by the AP Inspiration and Revo.

My point about the Revo is that it's pretty much a binary measurement when the second scrubber begins to be used and warms up. This gives an absolute reading that half of the scrubber has been used (actually slightly more as it's measuring the second scrubber, but round it to half). This means that the measurements can be very accurately gauged. A bonus is that provided the second scrubber's not been used, it can be swapped over with another, so only needs 1.35kg/4lb of lime for a fill.

I believe that 1.35kg equals 3lbs not 4lbs.

 

[broncobowsher]

2.2 pounds per Kg

 

[Divermikey]

2.2 pounds per Kg

correct so 1.35kg = 2.97lbs

 

[Gareth J]

The same reason there is no temp stick in a Meg, Kiss, Triton, Optima, SF2, Hollis, RB80, and others. It's an unneeded complication.

Granted. There has been a steady push to make Rebreathers 'safer', i.e. an attempt to take the 'diver' out of the equation.
The problem with that is that the more complexity, the more things to go wrong. Also, if you believe the unit is looking after you, you are not treating it with suspicion, and double checking it is functioning as expected.
Rebreather bite when you least expect it.

I am still in the camp that I always treat them as if they are going to go wrong at the least opportune moment. Rather than assuming they are looking after me and will warn me if they have a problem.

That said, I like my temp stick. Like PO2, is one of the items I monitor throughout the dive.

 

[rjack321]

Granted. There has been a steady push to make Rebreathers 'safer', i.e. an attempt to take the 'diver' out of the equation.

Does it bail you out automatically like a diving safety officer or an anesthesiologist? Cause you have to monitor it and decide what to do with that information. I haven't seen any data (even anecdotal) that CO2 hits in non-temp stick units are a common problem at all. And there are probably just as many people saying temp sticks lead to overconfidence and pushing sorb as there are temp stick fans saying they safer. So the jury seems to still be out in the safety element.

That said, I like my temp stick. Like PO2, is one of the items I monitor throughout the dive.

We all have limited capacity to process information. What are you paying less attention to by tracking your temp stick? I'm sure its not nearly as distracting as a camera, but it is "one more thing" and we all have a finite amount of bandwidth.

 

[Gareth J]

Does it bail you out automatically like a diving safety officer or an anesthesiologist? Cause you have to monitor it and decide what to do with that information. I haven't seen any data (even anecdotal) that CO2 hits in non-temp stick units are a common problem at all. And there are probably just as many people saying temp sticks lead to overconfidence and pushing sorb as there are temp stick fans saying they safer. So the jury seems to still be out in the safety element.

I started in the days of the original inspiration. So, the only instrumentation, the first generation had was PO2!
Absolutely with you on the bailout issue. I almost never dive without a bailout cylinder.

We all have limited capacity to process information. What are you paying less attention to by tracking your temp stick? I'm sure its not nearly as distracting as a camera, but it is "one more thing" and we all have a finite amount of bandwidth.

The checking the temp stick is in there with checking depth & time. Not quite up there with PO2 and cell behaviour. But less frequent than the checks of the camera.

The thing that really takes up "bandwidth" is adverse (zero) visibility and keeping contact with my buddy, or worse still two buddies on the rare occasions I'm in a three.