JJ vs Cmoptima vs Xccr(fx)

[lostsheep]

There are no good CO2 sensors for rebreathers at this time. There are some. some people even have good luck with them. But in general, they are finicky.

Is this a general statement or are you experiencing a higher rate of failure lately?

 

[GF99/99]

What makes you say this about the Triton? Just curious.

The Triton has is pro's and cons's when I got it at the time several years ago it seemed to be the best option for a chest mounted unit. But......

• I found the Monox secondary PO2 monitor computer to be very useless and the battery in it is horrible as well. I really hated the Monox so much so that I removed it and wired in another Petrel however this also removed the HUD as the HUD was controlled by the Monox so its a trade off.
• Second I am not a fan of molex o2 cell connections and I find it interesting that alot of units still use this connection. It will eventually corrode also the wires will eventually start to fail. I really like the JJ cells and connections the best. I like that the male end is fully potted and sealed to the head and then the wires are on the actual cell so every time you change cells you get new wires as well.
• I still have mixed feelings about the "clip" type connections, I have never had any issues with them but I just don't like them I think its a personal preference thing .
• I personally like regular dump valves for a CL dump, I can't say I hate the drysuit dump valve on the Triton CL but I also can't say its my favorite.
• With the two different size CL on the Triton I find that the WOB is a little strange, I know many other Triton divers don't have the same complaints I do but for me the inhale is super easy and the exhale is just a little bit more difficult than what I would want. But apparently this is how the Triton was designed.
• Lastly the way you close/open the scrubber canister is not the best, I find it is very easy to pinch the main o-ring also the weed wacker plastic to hold the canister together can sometimes be a PIA to install.
• Oh yeah and I really do not like the smurff blue loops

I think a lot of these are nit picking with the exception of the Monox computer (this thing is horrible) but I heard that the new Triton revision will not have the Monox anymore.

 

[GF99/99]

Heading off some insinuated FUD here.

JJ takes 2.3 kg of sorb:

THE JJ-CCR REBREATHER – JJ-CCR VERSATILE REBREATHER

Choptima, like its BM brethren , takes 2.2kg of sorb:

O2ptima CM - Dive Rite

The most versatile tool for underwater exploration. The simplicity of the O2ptima CM results in limitless possibilities of use. The O2ptima CM is fully compatible with whatever open-circuit system you’re currently diving: sidemount, back mounted doubles, or a single tank. The chest-mounted...

www.diverite.com

The weight of sorb can sometimes be misleading. What you really need to look at is the flow characteristics of the scrubber. You could have two scrubbers with the exact same weight and one might perform significantly better than another if they have different flow characteristics. This is where the CE scrubber rating come is handy, yes we all agree that the test is very unrealistic of what an actual human diver could do but it is a standardized test that puts all scrubbers on an equal playing field to see how they truly perform.

The JJ standard axial was CE rated at 3hr. There is no CE rating/test for the Choptima that I know of so its kind of hard to compare the them even though they basically hold the same capacity.

Also JJ has an optional drop in 3kg radial scrubber, and if you really want to go big they have an optional 4kg radial scrubber but this requires a new canister.

 

[lostsheep]

The JJ standard axial was CE rated at 3hr. There is no CE rating/test for the Choptima that I know of so its kind of hard to compare the them even though they basically hold the same capacity.

A lack of CE data does not indicate one way or another the relative duration of the scrubber.

Pardon the anecdotal evidence, but I personally know it’s good for more than 3 hours and I’m pretty sure there are many divers pushing it WAY longer than that.

I like my chop a lot but by no means am I a brand loyalist; I’m chiming in here just to head off fuD (deliberate emphasis on the D)

 

[broncobowsher]

Is this a general statement or are you experiencing a higher rate of failure lately?

General statement.
Been following stuff like this for years. While there is new tech for O2 monitoring (not that new, but trickling into the dive world) the CO2 monitoring just has not seen any great leeps. Still stuck with CO2 sensors don't like high humidity enviroments. Have not seen anything showing that there is anything that works in condensing levels of moisture and the huge pressure swings that diving goes through.
I still look for CO2 monitoring that is useful in diving. Someday it may exist. But I have not seen it yet.

 

[Fat old english bloke]

I think a lot of these are nit picking with the exception of the Monox computer (this thing is horrible) but I heard that the new Triton revision will not have the Monox anymore.

I flooded mine. Left the charging port plug at home on the table. Realised at 20m - in a quarry though, so I continued the dive with just the Petrel. The HUD has never worked for me either, so it was just at one of my periodic checks that I realised the thing was dead.

My intention was then to have the Monox/HUD removed and run a NERD instead, but taking it apart and a week next to the dehumidifier fixed it.

 

[sebdiver]

alright all thanks for the update looking foward for the JJ but still a lot of unknow into the CCR world! should I backmount 50s or having them on my side for bailout?!

 

[DiveLikeAMuppet]

alright all thanks for the update looking foward for the JJ but still a lot of unknow into the CCR world! should I backmount 50s or having them on my side for bailout?!

Learn to use stock unit to make your life easier? Most likely you will be taking a single ali80 as bailout in your first year of CCR diving.

 

[AJ]

alright all thanks for the update looking foward for the JJ but still a lot of unknow into the CCR world! should I backmount 50s or having them on my side for bailout?!

Depends on your config:
- Backmount = bailout as stage (although some strap big cilinders on the JJ itself with a lot of hoses, look for GUE JJ);
- Front mount: your choice. You can dive single/double setup on your back or sidemount with or without stages;
- Sidemount: you did not mention it, but there are sidemount rebreathers (would not recommend it as a first ccr btw). At least one stage is necessary.

Starting out, backmount is your best option in my opinion. The transition to ccr is somewhat easier if you don't have to learn how to dive an complete new system. Unless you're a very experienced sidemount diver of course.

 

[sebdiver]

Depends on your config:
- Backmount = bailout as stage (although some strap big cilinders on the JJ itself with a lot of hoses, look for GUE JJ);
- Front mount: your choice. You can dive single/double setup on your back or sidemount with or without stages;
- Sidemount: you did not mention it, but there are sidemount rebreathers (would not recommend it as a first ccr btw). At least one stage is necessary.

Starting out, backmount is your best option in my opinion. The transition to ccr is somewhat easier if you don't have to learn how to dive an complete new system. Unless you're a very experienced sidemount diver of course.

yeah I was looking at the GUE way, dunno if its the best way to rig everything!