Number of HP ports on first stage?

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Torontonian

Contributor
Messages
563
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20
Location
Toronto, Ont., Canada
# of dives
100 - 199
Hi.

I have purchase most gears except for BC/reg and am now looking to buy. Still learning about BC and reg options.

I see that most of the first stage being sold have 1 HP and 3 LP ports. Some even have only 2 LP ports and I don't know how that will work because you'll need one LP port for a regulator, an alternate regulator and one for inflator, unless the inflator also has the alternate air source.

If I like to get a computer console that shows air left (and depth and other things computers keep track of), it'll use one HP port. Many people recommend using the old SPG as a backup, but wouldn't that mean the first stage would need another HP port? In that case, wouldn't all these people need a first stage with 2 HP ports?

When looking at older year model or used regulators, most of the first stages only have 1 HP port. Did the first stages with two HPs cost a lot more, or is it because only in recent years people begin to make them with 2 HPs?
 
First stages with 2 HP ports don't really cost more because they have two ports, but more because that 2 ports come on the "higher end" regulators instead of the "lower end" ones. (now this is not always true, but is a lot of the time).

Do you need two HP ports? Nope. Not really?

What would you do with the 2nd HP port? You would either hook a analog pressure gauge to it as a backup with an air-integrated-hose-computer or you would hook a wireless transmitter to a wrist mount air integrated (& wireless) computer. The 2nd option of the wireless is much more common, especially today with advances in dive computer technology. You'll rarely see someone with a hose-air-integrated-computer that has a analog gauge backup, unless they are doing some sort of tech diving.

So if you can get a regulator with 2 HP ports, it's nice to have if you ever upgrade to a wireless transmitter air integrated computer.

I noticed you didn't ask about 4 LP port 1st-stages? This is common on a lot of regulators now also. Why would you want 4 LP ports? Well of course one for regulator, one for octo, one for power inflator. The 4th one is more common on divers who dive dry to inflate their drysuits (or remove the "pinch" from the drysuit). Ocassionally you'll see someone diving a dual-bladder BC who needs an extra power inflator.

hope that helps.

-mike
 
Unless you are using a inline octo your gonna want a minimum of 4 ports on thr LP end
second stage, octo, inflator, drysuit whip, as I see you are from Toronto a drysuit will be in your future eventualy.
 
Thanks for the explanations. I see if a first stange has 2 HP, then it usually has 4 LP already. Also, even though I'm in Toronto, I don't dive in cold or even cold water. I'm a warm water diver (I don't like the cold), and wouldn't like dry suit diving.

If I get a computer, I think I'd like an air integrated one (to also keep track of air consumption). So that will definitely take up one HP. I can see the advantage in using a transmitter to a wrist computer, but they seem to cost a lot more, and of course one more point of failure.

But are the advances in computers so good now that people don't really use an analogue SPG backup?
 
Torontonian:
But are the advances in computers so good now that people don't really use an analogue SPG backup?

I haven't seen any advances in computers that makes them run without batteries. And until I do, I'll be reading my tank pressure on an analog guage.
 
PerroneFord:
I haven't seen any advances in computers that makes them run without batteries. And until I do, I'll be reading my tank pressure on an analog guage.


Ditto. :)
 
1) The vast majority of people I see using some sort of digital pressure gauge, whether hoseless or not, use an analog SPG as a backup. This makes me wonder why even bother with the expensive hoseless pressure guage if you have to carry the analog SPG anyway. Just use the analog SPG. Only 1 HP port needed. You may also find it interesting that the vast majority of double tank divers use only one SPG.

2) You will need an LP port for your BC inflator, your primary regulator, your backup regulator, and, eventually (you live in Canada - this isn't a maybe) your drysuit inflator. Most regulators sold today have 4 LP ports for this reason.

If the regulator only has 3 LP ports, that's a good sign that it shouldn't be used in cold water.
 
Thanks for the responses.

Well, I don't like cold weather or cold water diving. And speaking of cold, Buffalo is getting hammered with snowstorm. It's 1 degree out and will snow here soon too. I won't be getting a drysuit.

It sounds like I should look for a first stage with 2 HP, which will most likely come with 4 LPs. I'd like to get an air integrated computer and use an analog SPG as a backup, but also to compare.
 
https://www.shearwater.com/products/perdix-ai/

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