Cell Replacement

Ant Slegg

There's been a lot of discussion recently about cell replacement so I thought I'd ask this question separately:

"What are the options and why?"

The basics I can think of are:
1) Replace all the cells at the same time (i.e. all 3)
2) Replace 1 at a time:
a) As a drift or other issue is noticed (cheapest option)
b) At a predetermined interval (i.e. 365 days)
3) Replace a majority at a pre-determined interval but leave one "old" cell in place

I don't like (2a).
With (2b) and (3) I am thinking that having a reference cell that gives some warning against infant mortality problems is a good idea BUT it does require some discipline.
With (1) the main issue appears to be the batch manufacturing problems I have read about elsewhere i.e. there is a chance of getting all bad new cells. Also there is a risk that all the old cells drift/fail in the same direction and such a problem would be more difficult to detect.

I am assuming no "independent" monitor is available (if so should use a different cell type?).

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Ant' S
Learning to dive since 1990...

Drmike

I test my cells before and after every dive and replace any that show signs of failure - dont care how old the cell is* - if it works it works

ususually, thankfuly, this means i end up replacing one at a time. Id feel very unhappy if i had to change all 3 cells at once, 2 is ok as i have a 3rd to compare against but 3 new ones offers no protection against batch errors

I always have a spare new cell with me should one fail.

*Genenerally the cells end up failing within 1st week or if they survive that they generally last 1 to 1.5 years of use, so on average id say cells end up getting changed every 12 months or so anyway.

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Get a girlfriend you sad twat - a Rebreather is an unfaithful mistress - dont blind yourself to her faults just because she goes down on you

lizardland

Same as what I do though I'm fighting the urge to change one of my cells as it's not far off 2yrs old. However, it reads bang on both at the start and end of the dive.

I also tend to stagger when I buy cells (unless I need two at once), I try to avoid buying more than one at a time if they aren't for immediate use.

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