DIR regulators...?

[jonnythan]

The Apeks DS4 first stage has *all* 3/8" LP ports. This is one of two good reasons to use the DS4 instead of the DST. Even still, a lot of people diving the DST use a small metal adapter that changes the 1/2" port to a 3/8" so that standard hoses can be used. Hose blown, replace it with another standard 3/8" hose. And, still, on all Apeks first stages that use a 1/2" port, there are three other 3/8" LP ports. The 1/2" port on some Apeks first stages is a non-issue.

Poseidon regulators are not DIR for many reasons, including the hose issue.

 

[Scubaroo]

Poseidon regulators are not DIR for many reasons, including the hose issue.

But that's only a second stage issue. Are there any *first stage* issues that would make them "non" DIR?

 

[jonnythan]

But that's only a second stage issue. Are there any *first stage* issues that would make them "non" DIR?

That's a good question. Are the ports 3/8"? I think they're supposed to have quite high IP's, but I imagine that's something you could turn down. I'd like to know if Poseidon first stages are DIR.

 

[d33ps1x]

Read above ^

 

[jonnythan]

Any Apeks reg with an X in the name (TX40, TX50, TX100, ATX40, ATX50, ATX200) will be DIR and a pretty decent second stage.

I'm not sure if there are any others that actually fit the long list of requirements to be a DIR reg... and I'm not sure that's an accident

 

[jplacson]

funny thing polkster, Zeagle regs are Apeks regs rebranded. Even Zeagle's Octo+ safe 2nd wasn't renamed, it's an Apeks Octo+.

 

[Greg Barlow]

Actually, the latest Zeagle regs are not Apeks models. They are based upon Apeks designs, but have some credible differences. After Air Liquide acquired Apeks, they no longer sold the rebadged models to Zeagle. Zeagle then made enough changes to avoid the patent headaches.

Greg Barlow

 

[jplacson]

Poseidon regs aren't DIR mainly because they are upstream regs. The cover of the new Xstream can be removed without any tools at all, and with only 2 fingers. (It's just a rubber cover that can be peeled off) I originally wanted this reg, but it was way too expensive considering that I'm not a tech diver.

Greg, was it air liquide or Aqua Lung that bought Apeks? Anyway, I think the Flathead series is still part of the Apeks ATX100 family. Not quite sure when Zeagle had to change the design, but I know that they still had a few Apeks rebadged regs on the shelves.

Anyway, for the sake of this forum, DIR doesn't like upstream regs...so Poseidon is out. AFAIK, Scubapro and Apeks are the recommended DIR regs... although not required. Even that, DIR would require you to plug the 1/2" port or use an adapter on it.

 

[Scubaroo]

Poseidon regs aren't DIR mainly because they are upstream regs.

Some Poseidon second stages are definitely upstream (hence the OPV on some Poseidon firsts), but are the first stages upstream or downstream? I had a look and couldn't find a definitive answer.

 

[Greg Barlow]

Some Poseidon second stages are definitely upstream (hence the OPV on some Poseidon firsts), but are the first stages upstream or downstream? I had a look and couldn't find a definitive answer.

A first stage actually isn't either. It merely reduces the incoming cylinder pressure to a predetermined intermediate pressue over the surrounding water pressure. For instance, let's say that a typical reg is adjusted to an IP of 140psi. At depth, the water pressure activates the first stage valve. The valve remains open until the internal pressure is 140psi more than the surrounding water pressure. At this point the valve closes. It will remain closed until the diver reduces the internal pressure by breathing, purging, or going deeper.

The general thought on DIR is that a first stage should have a fairly low IP, somewhere in the 120-130 range. This is intended to reduce the adiabatic cooling effect (only the overall gas volume is actually a factor here) and to reduce wear and tear on the HP valve seat.

Personally, I set my Mares first stages to 138psi for both warm and cold water diving. The higher the IP the easier it is to get high gas flow through a second stage. I prefer the 138psi as it still offers easy breathing without the large volume of gas that can typically lead to icing conditions.

Greg Barlow