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MTBF formulae?



#3

Does anyone remember what the (simplified) formulas are for
series and parallel MTBF's are? Are they basically the same
as the formulae for capacitors? [Adding MTBF's in parallel
in redundant configurations, and 1/(1/a+1/b) ??]

I realize that it can get a whole lot more complicated than
that when taking MTTR into consideration etc. But I just
need something simple to get some approximations (which they
all are anyway)...

Thanks.


#4

It would seem that I was being a bit too simplistic. I was trying to remember something I'd seen in the seventies.

I've found a few interesting references on the 'net which others may be interested in. Actually, the whole website these are from is very interesting. Does anyone have any other references to MTBF and availability math?

"Failure Rates, MTBFs, and All That",
http://www.mathpages.com/home/kmath498.htm

"Infinite Parallel Redundancy",
http://www.mathpages.com/home/kmath326.htm

Check out the entire website. http://www.mathpages.com/

Not the same as the old mathworld site, http://mathworld.wolfram.com/, but very good reading.


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