Regulators 101

[n733lk]

How does a "balanced" reg differ from a "non-balanced" reg?

 

[elan]

Balanced reg would minimize the effect of supply pressure fluctuations.

 

[Bubbletrubble]

@n733lk: FYI, the terms "balanced" and "unbalanced" can be applied to either the first or second stage.

This line of questioning is well-traveled territory.

Rather than re-hash all of the pros and cons of the various reg designs, you might find this previous SB thread, which focuses on balanced/unbalanced second stages, to be informative. There's a little bit of info on balanced/unbalanced first stages as well.

There's also this SB thread about balanced/unbalanced Sherwood first stages. halocline's post #6 has some general info about balanced/unbalanced first stages that you might find helpful.

 

[elmer fudd]

How does a "balanced" reg differ from a "non-balanced" reg?

A balanced reg means that the valves open just as easily regardless of pressure. On an unbalanced reg, as the pressure increases or decreases the effort necessary to open the valve will also increase and decrease slightly. There are two valves, one in each stage and either one can be balanced or unbalanced. Unbalanced regs can be cheaper to buy, cheaper to service and theoretically are more reliable since they are simpler. In the old days, before SPG's, divers also used to use them to gauge the amount of air left in their tanks. Balanced regs usually breathe slightly better.

I've got some of both and I don't think it matters that much. Generally, I would opt for a balanced reg, as easier breathing is always nice. Also for deep diving beyond 100' I would opt for a balanced regulator as the air is thicker at those depths.