Metric SAC rate off by a factor of 10 or so

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BarryInkpen
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Metric SAC rate off by a factor of 10 or so

Post by BarryInkpen »

I recently switched my dive computer to metric, and then selected metric for MacDive. All units convert ok except SAC rate. My normal rate is about 0.5 to 1.0 cuft/min. However, the SAC rate now shows up in the range of approx 130 to 190 litres/min. It should be about a tenth of that. My normal rate converts to 14 to 28 litres/min. Thoughts anyone?
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nick
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Re: Metric SAC rate off by a factor of 10 or so

Post by nick »

Your tank size is probably still in imperial (80 litres).

Tank sizes are not translated.
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BarryInkpen
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Re: Metric SAC rate off by a factor of 10 or so

Post by BarryInkpen »

nick wrote:Your tank size is probably still in imperial (80 litres).

Tank sizes are not translated.

Yes, you are correct. Not only does the tank data have to be metric but the data is in tank volume measured in how much water it would hold, as opposed to how much air can be compressed. So a 100 cuft tank which would hold 2832 litres of compressed air, is actually entered as 12 litres at 206 bar. Thanks for getting back. Barry
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nick
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Re: Metric SAC rate off by a factor of 10 or so

Post by nick »

Woops. I meant 80 CF in imperial, vs in metric where it's in litres. But you get the point. You're correct, they are different measurements. Hence they don't translate.
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