Question Digital pressure gauge

[DiverNordic]

Are digital pressure gauges reliable?
Would like one but have no experience with these.

 

[evandroairton]

If you are talking about digital SPG, cressi makes one
I've saw it at a friends dive shop, it's quite small, with good sized numbers and seens nice, but never used one

 

[Boofymac]

Been using the Cressi Digic 2 for 10 months now and logged more than 50 dives with it.
It conveniently shows all the information you need at a glance.
Very easy to read with large numbers on the display.
I have just purchased 2 more units for my daughter and granddaughter's kit, slightly dearer than an analog gauge but much more functional.
With regards to reliability time will tell but all the numbers line up with my garmin computer

 

[GDHLEWIS]

My CressiDigi2 died on me after 7 months of use. depth gauge on it is way off and the pressure readings are becoming slightly random. Now trying to workout if its worth sending back for a warranty check or not as DHL (Wouldn't trust the post office here)is nearly as much as buying a new SPG.

 

[broncobowsher]

Analog is going to win the reliable check. You can leave one in a box for 30 years, pressurize it, and it will work. Digital will have battery issues.

In general, most tech divers really want reliable gear. And you will find them using brass and glass gauges.

An analog gauges is easy to glance at and see what you need to know. During a dive you don't need an exact number. If you need an exact number, you are planning too close to the edge.

But digital does have it's place. For filling, mixed gasses, really good. I put transmitters on the rebreather to declutter the setup. 2 less things hanging off me. And the data logging for post dive analysis is a cool feature. But adds battery maintenance. Signal dropout during the dive. Actually reading the gauge numbers and not just checking that a needle is in the general range I would expect it to be in.

 

[NW Dive Dawg]

I dive an Oceanic Pro Plus 3 with digital pressure data and have had no issues... Really like the HUGE numbers for my old eyes......., battery status indicator and super easy user changeable battery. I do have an analog SPG for my pony bottle...

 

[stuartv]

Analog is going to win the reliable check. You can leave one in a box for 30 years, pressurize it, and it will work. Digital will have battery issues.

I will respectfully disagree.

If the digital was stored properly, with the battery removed, then it has good potential for installing the battery and being ready to go.

After that much time, the SPG has a very good chance of having a dry-rotted O-ring on its spool and blowing out as soon as you pressurize it.

All of which is kind of silly. Do we really care about the reliability after sitting for 30 years? Is anybody going to dive gear that has been sitting for 30 years without getting it serviced first?

That is not the kind of reliability I want to evaluate when facing this decision of digital vs analog.

If you do proper maintenance on your reg set, you'll change the digital gauge battery every year and then, in my experience, it will be more reliable than an SPG. "My experience" being with the PPS transmitters that are used by Shearwater, Oceanic, Aqualung, Hollis, and others.

O-ring blowout on an SPG spool is not at all uncommon.

An SPG needle "sticking" or being "off" at the very low end of its range is also not uncommon. The point there being that when an SPG "fails", a common failure mode is to give you a reading that is wrong but believable. In contrast, if a digital gauge fails, they will almost never give you a believable reading. They will either give you no reading at all or maybe some ridiculously high reading that you KNOW is wrong.

A wrong yet believable reading is far more dangerous than no reading at all.

 

[Gone for diving]

An SPG needle "sticking" or being "off" at the very low end of its range is also not uncommon. The point there being that when an SPG "fails", a common failure mode is to give you a reading that is wrong but believable. In contrast, if a digital gauge fails, they will almost never give you a believable reading. They will either give you no reading at all or maybe some ridiculously high reading that you KNOW is wrong

I'll take a mechanical gauge that's out at the low end, any day of the week, over a digital not working...

I'll still be diving with the mechanical... ( 200-300 psi out is not a big deal)

With a digital I can't really unless you like exciting dives..

Yes I expect a digital and mechanical gauge to last 30 year, in storage
One needs a battery, and one needs a spool. No big deal,

 

[Lorenzoid]

Does a digital SPG not have a so-called spool? My understanding is that the spool’s function is to enable the SPG to swivel on the hose. Wouldn’t a digital SPG also need to swivel?

 

[broncobowsher]

Does a digital SPG not have a so-called spool? My understanding is that the spool’s function is to enable the SPG to swivel on the hose. Wouldn’t a digital SPG also need to swivel?

Depends on the gauge and how it is installed. If installed on the end of a hose that swivels, yes it will have the same spool and O-rings. A transmitter screwed directly into a 1st stage, no.

Also keep in mind that the OP never stated this was an SPG while diving. Just digital vs. analog. So it could be panel mounted at a fill station. As far as SPG goes, there is wireless and wired.

Lets not forget in an SPG configuration that the digital will need a battery compartment that needs to be sealed, and seals can leak.

The analog gauges on my grandfather's welding torch set are probably 60 years old, they still work. I've rebuilt a few 30 year old car computers where the electrolytic capacitors have aged out. Pretty common stuff.

An analog gauge that is off a little bit is still reliable. May not be precise, but it is reliable. And the question was which is more reliable. Now ask which is more precise, hands down the digital. We can toss another word into the mix, accurate.

How far down the rabbit hole do you want to pour this can of worms?