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  #1  
Old November 4th, 2010, 03:32 AM
dvaidr dvaidr is offline
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Exclamation Failure Rate specification

I'm confused by something which I ought to know.

I have a failure rate of 0.01%/1000hours. How would one begin to put this into a prediction? Is it just mission time multiplication?

Sorry, prediction isn't my thing.
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  #2  
Old March 7th, 2011, 09:42 AM
thisisyousif thisisyousif is offline
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Default Re: Failure Rate specification

You mean that failure rate is constant in this case?
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Old April 15th, 2011, 04:13 PM
Kathleen Kathleen is offline
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Default Re: Failure Rate specification

Hi,

Since you already have the failure rate, and if you are attempting to put it into the Lambda Predict 3 software, you can use the External component. This will allow you to enter the Base Failure Rate.
For MIL/ NSWC standards, the failure rate equals 0.1 FPMH
For Bellcore/Telcordia standards, the failure rate equals 100 FIT

I hope that this helps.

Kathleen Laird
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  #4  
Old November 22nd, 2016, 03:46 AM
dvaidr dvaidr is offline
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Default Re: Failure Rate specification

I'm coming back to this one! I just cannot get my head around this at all.

Say, I'm wanting to specify this as FIT or 10^6. How would I go about it?
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  #5  
Old February 14th, 2017, 09:42 AM
Richard_UK Richard_UK is offline
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Default Re: Failure Rate specification

Sometimes we can get confused with notation and you may be overthinking this problem:

You have a failure rate of 0.01%/1000hours. In this case the percentage represents a fraction of a failure rather than a probability. 100% represents one whole failure. (I don’t personally like expressing failure rates in this way, because it is confusing.) So:

0.01%/1000 hours = 100% /10 000 000 hours
= 1 failure per 10 000 000 hours
= 0.1 failure per 1 000 000 hours
= 100 FIT

Does that help? or have I not understood the question?
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Last edited by Richard_UK; February 14th, 2017 at 09:44 AM. Reason: too many gaps
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