4 days is roughly 100 hours, so divide your 10000 by 100 = 100. 100 * 4 days is 400 days which is close to your figure. Did they lose a couple of 00's in printing the figure which might give you 40000 days. What sort of figure would you expect?
I remember at uni having to calculate the MTBF of a system by calculating on the MTBF of each component. I couldn't do it now. Peter On 10/06/2026 14:42, Ralph Corderoy wrote:
Hi, I was idly looking at this power convertor, and saw the ‘MTBF 10000h’. https://www.olimex.com/Products/Power-Supply/Modules/ACDC-85-255-5V0.7A/ That's quite a short time for an always-on device. $ units -1 10000hour time 1 year + 51 day + 10 hr + 11 min + 14.025322 sec Just long enough for a one-year warranty. :-) Not that MTBF works like that. Skimminghttps://en.wikipedia.org/wiki/Mean_time_between_failures, it is perhaps more of a MTTF value since I don't suppose they get repaired. And the odds of it lasting a year are about 42%. R(t) = e^(−λt) = e^(−t / MTBF) $ bc -l e(-(24*365)/10000) .41644536602038009593 Where have I gone wrong?
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