Reg. Question... what is what (HP and LP)

[Black-Gorrilla]

i got certified last year... dove a few times with rental... bought everything i need (mares v16 reg, mares bc, got octo, gauges, mask fins and so on) and use the reg a few times (no problems) but then went a while without diving... and decided to have everything cerviced before i hit the water again (better safe than sorry... its been about a year)

well... i never notice what goes were on the reg... got it all assembled at the LDS... and never looked at it that well (not usually my style) but...

just wondering what goes where?
what is HP and what is LP?
such as inflator, gauges, octo etc... all my stuff is getting checked out.. so im dying of curiosity...

thanks
long time reader here... first of many posts.

 

[Land Locked]

HP=high pressure, for your spg, tank pressure gauge.
LP=low pressure, for your inflator hose and second stages.

 

[Dannybot]

HP is high pressure, used for your guage, it reads the pressure inthe tank.. your gas guage if you will. Everything else in LP or low pressure, your lungs can only handle the regulated, lower pressure even at depth, I think it is in the 100 psi renge, same goes for your octo, since it is just another mouth piece, and you inflator, once again is low pressure since the baldder can only handle so much pressure, not to mention it only needs to barely exceed the ambient pressure. you will even notice that there is an over pressure valve on your bcd to vent if overinflated.

I hope this has been helpful, and I also hope it is faily accurate.\

Danny

 

[Ed Palma]

As everyone else stated before, HP is the high-pressure side of the reg, and it measures the pressure within the tank. The pressure within the other hoses (inflator, primary 2nd and octo) is more correctly known as the intermediate pressure (or IP), which is approximately 120-140 PSI above ambient pressure. Low pressure is what is given by the 2nd stage (or demand valve), and is equal to the surrounding pressure.

 

[spectrum]

HP is high pressure, used for your guage, it reads the pressure inthe tank.. your gas guage if you will. Everything else in LP or low pressure, your lungs can only handle the regulated, lower pressure even at depth, I think it is in the 100 psi renge, same goes for your octo, since it is just another mouth piece, and you inflator, once again is low pressure since the baldder can only handle so much pressure, not to mention it only needs to barely exceed the ambient pressure. you will even notice that there is an over pressure valve on your bcd to vent if overinflated.

I hope this has been helpful, and I also hope it is faily accurate.\

Danny

Your lungs can't handle the low pressure output of your first stage but the second stage (mouthpiece part) can. The second stage delivers the air to the diver equal in pressure to the ambient pressure. The LP is usually in the 135-150 PSI range and will usually increase with depth so that the initial pressure differential to ambient is a constant. This allows consistent performance as you go deeper. This is true for primary and secondary second stages. The secondary (octo) is merely adjusted to crack on a higher draw to avoided unwanted free flows.

 

[ekewaka]

HP is high pressure, used for your guage, it reads the pressure inthe tank.. your gas guage if you will. Everything else in LP or low pressure, your lungs can only handle the regulated, lower pressure even at depth, I think it is in the 100 psi renge, same goes for your octo, since it is just another mouth piece, and you inflator, once again is low pressure since the baldder can only handle so much pressure, not to mention it only needs to barely exceed the ambient pressure. you will even notice that there is an over pressure valve on your bcd to vent if overinflated.

I hope this has been helpful, and I also hope it is faily accurate.\

Danny

You are mostly correct. Your lungs really can't handle anything more than ambient pressure. The 1st stage drops the pressure down from whatever is in the tank to about 135-150 above ambient, and the 2nd stage drops drops it the rest of the way down to ambient pressure.

 

[Black-Gorrilla]

i should have stated that i know what LP and HP actually stand for.. i just never took note of what goes in where in to the 1st (or comes out actually)
the v16 has 4 lp and 2 hp... so i guess that means that my 2nd and octo as well as inflator are on low, and the gauge on high.
thanks all for the fast reply.

 

[Dannybot]

Thanks for the corrections, I suspected that the 130 ish psi was high, but was not sure. I thought after I posted that it shouldn't need to get greater than 3-4 atm for rec diving, which would make it about half of that.

 

[Walter]

Unless you have a reg from before about 1985, the HP & LP ports are not the same size, so you can't put the wrong hose in the wrong port.