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Failure Rate Table Formulae |
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Failure Rate Table Formulae |
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Failure Rate Table Formulae
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Failure Rate Table Formulae |
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Failure Rate Table Formulae |
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When using a failure rate table, enter the reliability data actually observed at specified temperatures. RAM Commander then extrapolates failure rates for temperatures outside the specified domain, and interpolates failure rates for temperatures within the specified domain.
The Interpolation and Extrapolation works differently for Electronic/Electro-Mechanical and for Mechanical parts. Pay attention to Family selection in the GPRD library General data screen:
Interpolation and Extrapolation for Electronic/Electro-Mechanical parts
Interpolation and Extrapolation is performed using RIAC Reliability Toolkit formulas for compound electronic equipment:
Extrapolated failure rates are computed as follows (taken from RAC’s Reliability Tool Kit):
where
λ0 |
known failure rate for temperature t0 |
λ |
required failure rate for temperature t > t0 |
Interpolated Failure Rates
Interpolated failure rates are computed as follows:
Case A:
where
λ1 and λ2 |
known failure rate for temperature t1 and t2, respectively |
t |
temperature for which failure rate is to be evaluated. |
Case B:
Interpolation and Extrapolation for Mechanical parts
Interpolation and Extrapolation for mechanical parts is linear and is performed by any 2 closest points.
