The Reliability Test Plan feature computes required sample sizes, censor times, or precision, for estimating failure times and failure probabilities.
To launch the Reliability Test Plan calculator, select DOE > Sample Size and Power, and then select Reliability Test Plan. Reliability Test Plan Window shows the Reliability Test Plan window.
Reliability Test Plan Window
Interval Ratio is sqrt(U/L), the square root of the ratio of the upper and lower limits.
Two-sided Interval Absolute Width is U-L, the difference of the upper and lower limits.
Lower One-sided Interval Absolute Width is T-L, the true value minus the lower limit.
Two-sided Interval Relative Width is (U-L)/T, the difference between the upper and lower limits, divided by the true value.
Lower One-sided Interval Relative Width is (T-L)/T, the difference between the true value and the lower limit, divided by the true value.
After the Continue button is clicked, two additional statistics are shown:
1.
Select DOE > Sample Size and Power.
2.
Select Reliability Test Plan.
3.
Select Weibull from the Distribution list.
4.
5.
6.
Select Two-sided Interval Absolute Width from the Precision Measure list.
7.
Select Estimate time associated with specified failure probability.
9.
Enter 2500 for Censor Time.
10.
Enter 200 for Precision.
11.
Click Continue. Reliability Test Plan Results shows the results.
Reliability Test Plan Results
A reliability demonstration consists of testing a specified number of units for a specified period of time. If fewer than k units fail, you pass the demonstration, and conclude that the product reliability meets or exceeds a reliability standard.
The Reliability Demonstration feature computes required sample sizes and experimental run-times for demonstrating that a product meets or exceeds a specified reliability standard.
To launch the Reliability Demonstration calculator, select DOE > Sample Size and Power, and then select Reliability Demonstration. Reliability Demonstration Window shows the Reliability Demonstration window.
Reliability Demonstration Window
Reliability Demonstration Plot
1.
Select DOE > Sample Size and Power.
2.
Select Reliability Demonstration.
3.
Select Weibull from the Distribution list.
5.
Enter 2 for Max Failures Tolerated.
6.
7.
Enter 0.9 for Probability of Surviving.
8.
Enter 800 for Time of Demonstration.
9.
Click Continue. Reliability Demonstration Results shows the results.
Reliability Demonstration Results