Re: The Good Capacitors Photo Thread
I can see how you got where you got then.
I don't consider endurance.
To me the endurance rating isn't a very practical (realistic) number.
First they don't test the capacitors to failure so it's an 'at least this long' rating. [not a max] - It says "We can abuse it xxxx many hours and it will still work properly."
xxxx is CHOSEN by the testers before the test is done and is not determined by the testing. (Which is why they are all in thousands of hours: 1000, 2000, 3000, ..... )
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It does nothing practical towards telling us how long the cap last in a real world environment.
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Yes you can use endurance and do the math to find expected life span but that's almost useless because it's so inaccurate.
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I've forgotten which but one of the major manufactures (good caps brand) gives calculations of life span based on the endurance a "60% level of confidence" (their words.) This is because so many of the inputs to the equation are taken for other equations that give low precision results.
(Many inaccurate variables gives an even less accurate result.)
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So, even if you do all the math and come up with say 5 years, it doesn't mean the cap will last 5 years. It means it will last somewhere between 3 and 7 years.
[ 5 years +/- 40%.]
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So lets say we compare a 2000hr [5yr] cap and a 4000hr [10yr] cap.
5yr + 40% = 7yr
10yr - 40% = 6yr
-
In the real world the 2000hr cap may last longer than a 4000hr cap.
.
I can see how you got where you got then.
I don't consider endurance.
To me the endurance rating isn't a very practical (realistic) number.
First they don't test the capacitors to failure so it's an 'at least this long' rating. [not a max] - It says "We can abuse it xxxx many hours and it will still work properly."
xxxx is CHOSEN by the testers before the test is done and is not determined by the testing. (Which is why they are all in thousands of hours: 1000, 2000, 3000, ..... )
-
It does nothing practical towards telling us how long the cap last in a real world environment.
-
Yes you can use endurance and do the math to find expected life span but that's almost useless because it's so inaccurate.
-
I've forgotten which but one of the major manufactures (good caps brand) gives calculations of life span based on the endurance a "60% level of confidence" (their words.) This is because so many of the inputs to the equation are taken for other equations that give low precision results.
(Many inaccurate variables gives an even less accurate result.)
-
So, even if you do all the math and come up with say 5 years, it doesn't mean the cap will last 5 years. It means it will last somewhere between 3 and 7 years.
[ 5 years +/- 40%.]
-
So lets say we compare a 2000hr [5yr] cap and a 4000hr [10yr] cap.
5yr + 40% = 7yr
10yr - 40% = 6yr
-
In the real world the 2000hr cap may last longer than a 4000hr cap.
.
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