What else goes in HP port other than AI?

[RJP]

What else goes in the 2nd HP port if the 1st one has an AI transmitter?

An SPG, for when your AI transmitter goes frazzle.

 

[johnnyscience]

Ok I ordered a Mares Prestige 12 the other day from LP, so hopefully they included all of the port plugs and also properly tuned the reg for me.

If you don't install a port plug in an unused LP or HP port...then your first stage will be leaking gas once it's pressurized. Plain and simple.

First stages that are bought new should come with port plugs for all of the LP and HP ports. For the customer's convenience, some online dive shops completely assemble the reg before shipping it out, which includes attaching the second stages (LP hose), SPG (HP hose), and BCD inflater hose to the first stage in addition to making sure that the first stage is properly tuned (IP in the appropriate range) and the cracking pressures on the secondary stages are reasonable. Brick-and-mortar dive shops offer this same service. If the dive shop does this for your new reg setup, make sure that the LP and HP port plugs are included with your completely assembled reg. You paid for them, so you should have them. I recommend adding the port plugs to your save-a-dive kit. You never know when they might be useful for you or a dive buddy. Moreover, they come in handy if you ever want to service your first stage on your own.

Enjoy your new reg setup...

 

[iztok]

An SPG, for when your AI transmitter goes frazzle.

My AI (on UEMIS) never gone frazzle so far. The one on D9 did on occasion.

I do use SPG in any case. I find it most usable when I do pre-dive check before I go into the water as one would see the pressure drop when breathing if valve is not opened enough.

 

[LeadTurn_SD]

Even if you don't need all the ports, having extra sometimes simplifies routing. One of my regs only has one HP port, but darned if it's not on the wrong side for what I wanted to do with it.

Ding ding ding!!! We have a winner!!!

Having "extra" ports allows additional hose routing options, especially when using the 1st stage on a doubles rig, etc.

Best wishes.

 

[g1138]

Port plugs?

 

[g1138]

Ok I only plan on warm water reef diving, so a hose for drysuit doesn't apply.

I guess I'll have an extra port for each setting. A SPG could fill up the last HP port.

Are these port plugs a good idea for unused ports? Do they come with regulators or do you have to buy them separate? (my reg will be here tomorrow via Ups so I'm not sure what it comes with yet)

Port plugs are the plugs that should come installed in ever brand new reg.
They act like a dust cap for unused ports.
You remove them with an allen wrench.

On a side note, does anyone know if air escapes the 1st stage if you have an empty port? Or would air only escape if you were to activate the piston/diaphram of the 1st stage?

 

[LeadTurn_SD]

...On a side note, does anyone know if air escapes the 1st stage if you have an empty port? Or would air only escape if you were to activate the piston/diaphram of the 1st stage?

From an empty HP port, air would escape at high pressure (tank pressure).

From an empty LP port, air would escape at Intermediate Pressure (IP).

Either case, your first stage "throws a hissy fit" when you pressurize it, and everyone around you frowns and shakes their heads

Just kidding (about the frowns, not about the empty ports)

If you do not have a hose or transmitter in the port, it must be sealed with a port plug.

Best wishes.

 

[aquaregia]

On a side note, does anyone know if air escapes the 1st stage if you have an empty port? Or would air only escape if you were to activate the piston/diaphram of the 1st stage?

Well, I suppose gas will only escape when the piston opens, but by definition the ambient pressure exposed by the missing port plug is less than the sum of the ambient pressure and the intermediate pressure, so the piston will open due to the demand of the missing port plug.

In other words: yes to both options.

 

[g1138]

haha
Makes sense. I was too lazy to pull out my reg and give it a good look.
I wish I had Dave's half reg in my hand again.

Just kidding (about the frowns, not about the empty ports)

Pretty sure I'd be the only one frowning, while everyone else just throws a wide smirk my way. ;]

 

[LeadTurn_SD]

The ports provide unobstructed access to the interior of the first stage. If the tank valve is turned on and the first stage is pressurized, air will escape from an open port. The open port will cause the piston or diaphragm 1st stage high pressure "valve" to remain in an "open" state.

The piston or diaphragm react and respond to changes in ambient pressure (are depth compensating) and changes in internal pressure (demand from inhaling). But for the 1st stage "valve" to close, back-pressure is required. In both piston and diaphragm regs, the 1st stage "valve" is open with the regulator unpressurized and purged, and only closes when you pressurize the regulator and back-pressure is encountered. If a port is left open, you cut a hose, or depress the purge button, back-pressure is lost, the 1st stage valve "opens", and air flows until back-pressure is reestablished (or the tank empties).

Best wishes.