Computer that Displays SAC During Dive

[dfx]

Since we're already discussing terminology and I'm a metric guy, allow me to be awkward and point out that the liter is already a measure of volume. So you have either liters per minute (L/min) or cubic feet per minute (ft³/min), but not cubic liters per minute (L³/min).

 

[Akimbo]

Oceanic's Oceanlog software calculates and displays SAC as a volume (cu ft.) per minute. Call it what you will...that's the number I'm most interested in.

I didn’t really notice until this thread but Diving Log 5.0 also labels volume/minute data imported from the Cobalt as SAC instead of RMV. I never really gave it that much thought since the unit is Ft³/minute.

However, tomfcrist is right to point out the correct term. Just think how confusing it must be for a newbie trying to learn this stuff and seeing the two acronyms being used interchangeably!

... So you have either liters per minute (L/min) or cubic feet per minute (ft³/min), but not cubic liters per minute (L³/min).

Thanks, correction made. Typing and thinking don't always play well together.

 

[Triker]

Thanks for the input, folks. Good to know I was using the incorrect term--I am looking to know my RMV. An end-of-dive summary RMV is acceptable if the dive computer can display that for me without having to connect to a computer. Though not exactly what I'm looking to see, it is one data point in assessing the overall dive.

 

[NAM001]

What i did in tha past was to download to the cmoputer and display the dive data. A little archaic but if you have time and psi for any 2 points of the dive you can calculate the answer. The bigger paroblem would be in keepng track of what you did at various times to corrolate activity to the data.

 

[RonR]

<snip>... I was holding out for the Atomic Cobalt 2 however am not sure it will display SAC during the dive. I do not believe the old one did however I have seen indications the UI will be changing.

Like the original Cobalt, the Cobalt 2 will calculate and display RMV for each dive in the divelog summary screen, the UI is very similar.


If you step through the graphic dive profile you can see your tank pressure average for each segment (default is 30 second storage interval, but others can be set), along with the average depth for the segment- so you could calculate RMV for any group of segments in the dive.


You can get all this without connecting to another computer, it's onboard. But it doesn't display RMV during the dive, only the calculated gas time remaining.

Ron

 

[rwkosh]

The Uemis SDA will provide the info during any particular part of a dive. The computer has had some issues and is expensive. I'd suggest you do some research before considering it.

 

[dave22387]

The cochran Gemini gives psi per minute in real time. It will yell at you if your rate goes above what you set for the alarm... ie. I shoot fish and bull shark wants fish. Breathing rate goes up and computer yells. I force breathing rate down. It doesn't help with the shark though...

 

[scubadada]

For a dive computer to calculate RMV in real time, you would need to enter both the cylinder volume and working pressure for that particular dive. The computer would then need to calculate the average depth and pressure drop for the time period being calculated.

 

[dive_turkey]

Your best bet, I imagine, would be to stow waypoints or bookmarks. The Suunto cobra has a marker drop that will show again when you download the file to whatever digital log book you're using. I would think you could drop a marker before and after each activity, then look at your air consumption within that period of time and compare it to your overall average on a normal dive without the activities you're attempting to measure. I use MacDive, and at any point when reviewing my dive profile I can see the time in the dive, my depth, and my pressure. So as long as I know when said activity began and ended, I could then determine the amount of air I sucked down during that time.

 

[Grocio]

I know the original post is old but, just in case: the Mares Icon HD with air transmitter does.