uwxplorer
Contributor
First, the rMS should in principle detect channeling: by definition, channeling would allow most of the gas to flow unfiltered, stopping or at least reducing the CO2 conversion reaction and therefore resulting in a drop in temperature. I was planning on testing this in my unit at home with a straw inserted in the canister, but never got around to doing it, and now that my rMS is dead, I can't.
I recall (other forums) some chanting the merits of the rMS which had (supposedly) saved their life or their buddy's life, by reporting a drop in RCT (remaining cycle time, i,e. when do you need to dump your top canister). Upon checking their unit, they discovered a flood. So there might be some merit to it as a warning system, in principle.
HOWEVER, I have experienced (and reported) many occurrences of the rMS telling me on one dive that my RCT was dangerously low, while I knew by experience (and according to rEvo non-rMS recommendation) that my scrubber should be fine, ignored that warning, only to see the RCT jump back to normal on the next dive. In other words, I was correct in suspecting the rMS figures to be bogus and ignoring its dire warnings. This were never challenging dives, so I was not taking any risk by ignoring the "warning".
Similarly, I have started a standard 1 hr dive with plenty of RCT remaining (shallower than the previous one, which allowed me to take the RCT prediction as a safe margin of what was left), only to see the RCT dropping precipitously in the middle of the dive. Keep in mind that the rEvo has two scrubbers back to back, so getting a RCT of 0 is fine, since the reaction is supposed to now take place in the second one (and is indicated as a RST, or remaining scrubber time).
Should I have suspected channeling? There was certainly no flooding that I could detect, and as a precautionary measure, I just dumped both scrubbers after the dive, but you get the point: sometimes the rMS would sound alarming when, if the scrubbers were packed right and the unit tight, there was no reason to suspect that there would be any risk of overloading the scrubber, or some other times, the rMS was clearly taking a lot of time to make its algorithm converge, after throwing some initial alarming warnings.
Since what the rMS is doing is a trade secret (but that apparently this is not an issue to get a CE rating), there is no way to know what rEvo is cooking up with the temperature sensors (not mentioning the information on sex and body mass) to come up with these numbers.
I have suggested that a mere reaction front information would be much more informative than this "prediction", like a tank gauge is in many ways more reliable than the estimation of "miles remaining" in a car (since it makes no assumption about driving and traffic patterns).
Anyway, to go back to the original topic, rMS or not, proper packing and unit maintenance, as well as scrupulous pre-dive checklist are probably more important to a precisely timed prebreath.
I recall (other forums) some chanting the merits of the rMS which had (supposedly) saved their life or their buddy's life, by reporting a drop in RCT (remaining cycle time, i,e. when do you need to dump your top canister). Upon checking their unit, they discovered a flood. So there might be some merit to it as a warning system, in principle.
HOWEVER, I have experienced (and reported) many occurrences of the rMS telling me on one dive that my RCT was dangerously low, while I knew by experience (and according to rEvo non-rMS recommendation) that my scrubber should be fine, ignored that warning, only to see the RCT jump back to normal on the next dive. In other words, I was correct in suspecting the rMS figures to be bogus and ignoring its dire warnings. This were never challenging dives, so I was not taking any risk by ignoring the "warning".
Similarly, I have started a standard 1 hr dive with plenty of RCT remaining (shallower than the previous one, which allowed me to take the RCT prediction as a safe margin of what was left), only to see the RCT dropping precipitously in the middle of the dive. Keep in mind that the rEvo has two scrubbers back to back, so getting a RCT of 0 is fine, since the reaction is supposed to now take place in the second one (and is indicated as a RST, or remaining scrubber time).
Should I have suspected channeling? There was certainly no flooding that I could detect, and as a precautionary measure, I just dumped both scrubbers after the dive, but you get the point: sometimes the rMS would sound alarming when, if the scrubbers were packed right and the unit tight, there was no reason to suspect that there would be any risk of overloading the scrubber, or some other times, the rMS was clearly taking a lot of time to make its algorithm converge, after throwing some initial alarming warnings.
Since what the rMS is doing is a trade secret (but that apparently this is not an issue to get a CE rating), there is no way to know what rEvo is cooking up with the temperature sensors (not mentioning the information on sex and body mass) to come up with these numbers.
I have suggested that a mere reaction front information would be much more informative than this "prediction", like a tank gauge is in many ways more reliable than the estimation of "miles remaining" in a car (since it makes no assumption about driving and traffic patterns).
Anyway, to go back to the original topic, rMS or not, proper packing and unit maintenance, as well as scrupulous pre-dive checklist are probably more important to a precisely timed prebreath.
