Shearwater Owners with AI, do you dive with a SPG?

[Belzelbub]

If you're using Shearwater computers, the batteries can be easily replaced in situ. 30 seconds to unscrew the battery compartment with a coin and replace the battery. Not the case with Suunto who seem to think you'll take it to a local dive shop for a gouging as you need to remove the transmitter and unscrew some screws...

Additionally, if you are using PPS transmitters with your Shearwater computer, the tool that was provided by Shearwater works perfectly for both battery compartments. My SAD kit includes the tool, batteries for both, o-rings for both should I need to change them unexpectedly. Hasn't happen.

An ounce of prevention goes a long way. I change the batteries in my transmitter annually. That's way earlier than necessary, but it's easy for me to remember, doesn't cost much, and it works. I've never seen a low transmitter battery warning on my computer or in my dive log.

My tank valves don't get bumped into the on position, so that's a non-issue. However, even if they did, it shouldn't mean a significant problem. Might add up to an hour of on-time worst case considering the boat ride. For longer car rides, I'd probably assemble at the site.

 

[Rafael Moreira]

This video is from a year ago, and it's nice to see that there's no right or wrong on this subject. Even people who are 'considered pros' have mixed opinions. In the end, it will come down to what works for you and how comfortable you are. I just got a Perdix 2 AI, never used AI before, and I'm planning to use both on my first dives. I'm willing to remove the SPG once I feel comfortable with the new computer. Happy dives!

 

[NAUI Wowie]

There's a battery in the dive computer. It should warn you if it's too depleted to last the dive.

There's also a battery in the AI transmitter(s). If that battery is dead, as will happen if you leave it switched on under pressure, then you'll need to replace it. If the battery is low, it should "warn" your dive computer that the battery is low (this happens with Shearwater).

SAFT batteries last a lot longer than most others. BUT SAFT batteries will suddenly drop their voltage at the end of their life.

If you're using Shearwater computers, the batteries can be easily replaced in situ. 30 seconds to unscrew the battery compartment with a coin and replace the battery. Not the case with Suunto who seem to think you'll take it to a local dive shop for a gouging as you need to remove the transmitter and unscrew some screws...


My experience with my two AI transmitters on my rebreather are that it seems to be an annual thing that at the end of the AI battery, the Diluent transmitter will probably not work when turning on the gas if the unit's been unused for a couple of weeks. Not a problem as I just replace both batteries at the same time and that's that for another year.

The Perdix & Petrel I monitor the voltage as part of my build process and when it starts to fall I'll simply replace the battery. I've seen a low battery warning once on a dive; the computer worked for the whole dive.

thats what I just said. itll let you know its low before the dive. Why are you telling me what I already know? No offense. Dont make me say DUH

 

[NAUI Wowie]

 

[Wibble]

The problem is getting genuine SAFT batteries....seems that its just as likely to get cheap/useless chinese knockoffs as the real thing. What source do you use for Saft? I have a Predator that only uses SAFT and I'd like to power it up again.

Surprisingly Amazon have been good. Don’t go the the pikey too cheap to be true advertisers. Do wish Amazon would get rid of them, or even have an easy way of reporting them.

Also used a UK online battery specialist BatteryStation.co.uk

 

[NAUI Wowie]

Surprisingly Amazon have been good. Don’t go the the pikey too cheap to be true advertisers. Do wish Amazon would get rid of them, or even have an easy way of reporting them.

Also used a UK online battery specialist BatteryStation.co.uk

NEVER buy batteries on amazon. all identical products from different sellers are put in the same bins. So even if you use a safe seller you can get fake products. Amazon will never stop this practice. Profits trump real vs fake for them. They are just a distributer.

 

[Wibble]

thats what I just said. itll let you know its low before the dive. Why are you telling me what I already know? No offense. Dont make me say DUH

It depends.

With a Shearwater you can go to the voltage page which give a much better idea of the battery state, especially if you’re noting the battery voltages on each build. SAFT batteries suddenly drop and this doesn’t show up on the battery "gauge" widget.

Of course if the computer failed, you’d just swap to one of your backup computers.

If the AI battery failed during a dive it’s a little inconvenient on a rebreather and not a reason to call the dive. AI is somewhat more important on open circuit, hence many would back up AI with a visible SPG

 

[Caversluis]

No

I use my SPG for my final pre-dive check; 2 breaths from my primary regulator and 2 breaths from my secondary. The needle on the SPG should not move. If it does, it indicates that the cylinder is not fully open.

The Swift transmitter updates every 5 seconds or so (according to the manual). This will not show the ”needle drop” that an SPG would show.

 

[broncobowsher]

NEVER buy batteries on amazon. all identical products from different sellers are put in the same bins. So even if you use a safe seller you can get fake products. Amazon will never stop this practice. Profits trump real vs fake for them. They are just a distributer.

I will buy batteries only from some sellers. Not the low cost option. I have given up on SAFT batteries, the Energizer Ultimate Lithium work great for me. To the point that even after I use them on the Shearwater I will get a little more life out of them by putting them in clocks. I get as much life out of a used up Lithium as a new Alkaline battery without killing the clock when the battery dies.

 

[Capt Jim Wyatt]

the Energizer Ultimate Lithium work great for me.

They will not work in a Shearwater Predator. Only SAFT will work and as I stated above - finding reliable vendors for SAFT has been elusive for me.