FACTORY CALIBRATION?

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Bigbella

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I once asked, during a Poseidon tech course, whether there was a bit of latitude when it came to IP settings. The answer, from the instructor, looking over bifocals at me, had been a terse "absolutely not" at the time and "pay attention to the manual" -- even though settings had changed a bit over the years, toward a lower IP.

A friend just bought a bunch of gear for his wife, including an Xstream, and wanted me to assemble everything and check it out, right out of the box, still with the shiny, relatively new "calibrated" sticker that Poseidon had been plastering on its first stages.

The setting for that regulator and most of the other models, is 8.5 bar (about 123 psi); and the new "calibrated" regulator initially registered 9.6 bar (about 139 psi) before cycling it a few times, until it finally settled at 9.35 bar (a bit higher than the photo) -- not a big issue really, but sort of amusing considering how stringent their instruction and manuals were -- and that I would likely have been given a failing grade, had I done that, at least at the shop where I had worked as a kid.

Off to the Allen wrenches . . .
 

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Or maybe your IP gauge is not calibrated? :stirpot:
Please . . .

It has been calibrated and I also compared it to my analogue gauges as well as the to the IP gauge of my
test bench.

They all jibe.

When I worked at shops as a kid, it was all-too common to have new gear arrive with improper IP; that, apparently, has not changed in the interim . . .
 
How is your gauge calibrated?

For me, I can get into the instrumentation lab at work, if they are having a good day and I can check against there calibrated standards that are traceable back to national standards.

But I also go with a lot of slop in factory builds that have been sitting on the shelf for a long time and never broken in. I am happy with "in range" and not after an exact number.
 
How is your gauge calibrated?

For me, I can get into the instrumentation lab at work, if they are having a good day and I can check against there calibrated standards that are traceable back to national standards.

But I also go with a lot of slop in factory builds that have been sitting on the shelf for a long time and never broken in. I am happy with "in range" and not after an exact number.
I have an old college friend who runs a calibration service company in the Silicon Valley who services my tool cache on an annual basis -- and, in exchange, I maintain his regulators . . .
 
I have an old college friend who runs a calibration service company in the Silicon Valley who services my tool cache on an annual basis --and, in exchange, I maintain his regulators . . .
In that case, I completely trust your numbers.
 
I once asked, during a Poseidon tech course, whether there was a bit of latitude when it came to IP settings. The answer, from the instructor, looking over bifocals at me, had been a terse "absolutely not" at the time and "pay attention to the manual" -- even though settings had changed a bit over the years, toward a lower IP.

A friend just bought a bunch of gear for his wife, including an Xstream, and wanted me to assemble everything and check it out, right out of the box, still with the shiny, relatively new "calibrated" sticker that Poseidon had been plastering on its first stages.

The setting for that regulator and most of the other models, is 8.5 bar (about 123 psi); and the new "calibrated" regulator initially registered 9.6 bar (about 139 psi) before cycling it a few times, until it finally settled at 9.35 bar (a bit higher than the photo) -- not a big issue really, but sort of amusing considering how stringent their instruction and manuals were -- and that I would likely have been given a failing grade, had I done that, at least at the shop where I had worked as a kid.

Off to the Allen wrenches . . .
What's important to remember is that because the Poseidon second stages are unbalanced they are all going to be much more sensitive to IP than a balanced second stage and their breathing characteristics actually change considerably. If you run an Xstream/Jetstream at 139 instead of 123 you can actually tell by the way it breathes since the resistance curve is different and much more stark at 139 instead of 123. It's very different than unbalanced downstream second stages as well, the pilot valves are really finicky.
 
What's important to remember is that because the Poseidon second stages are unbalanced they are all going to be much more sensitive to IP than a balanced second stage and their breathing characteristics actually change considerably. If you run an Xstream/Jetstream at 139 instead of 123 you can actually tell by the way it breathes since the resistance curve is different and much more stark at 139 instead of 123. It's very different than unbalanced downstream second stages as well, the pilot valves are really finicky.
My first exposure to the Jetstream had been the 'Thor" or "Oceanair" -- and the 2940 was adjusted to then-current specs of 12.5 bar (about 181 psi!) -- and I have long wondered whether that negative view some divers had of Poseidon regulators, back then, had stemmed from that time when IPs were cranked somewhere into the stratosphere?

There had been a 4 bar (58 psi) reduction, across the board, in Poseidon IP settings for just about everything, save for the Cyklon; and even that one has come down a bit as well, to a current 10 bar, from the original 12.5.

I went diving with an old friend, on the spur of the moment, in late November (who had been a ScubaPro devotee for decades -- though I still allowed him in my truck) and lent him one of my Xstreams; and he was bowled over by its ease of breathing, having anticipated some ill-tuned shotgun inhalation that he had been told was the norm.

I've said it before: any incompetent can turn a Maserati into a Pinto on Firestone 500s . . .
 
https://www.shearwater.com/products/teric/

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