System reliability

[sandrine]

Hello,

Can everyone please explain me how to determine total acceleration factor and the reliability of a automotive product?
I have the following problem:

A test file is conducted on this product .
(eg high operating temperature then temperature-humidity and these tests are on the same product )

Is it possible to determine total acceleration factor (2 kinds of stress which have been applied successively and not simultaneously) and the reliability of the product ?

Please help .
Regards

[tarik]

Since you are applying a Temperature stress then a Temperature-Humidity test, I suggest you use the Temperature-Humidity Model (available in ALTA). In the beginning, since you are not applying high humidity, I would set the value of humidity to normal use level (or zero, if you think there is no humidity at all) and set the value of temperature, then in the second stage of the test, you can specify the new value of temperature and humidity level.
For more information about this model refer to http://www.weibull.com/AccelTestWeb/temperature_humidity_relationship_chap_.htm

Other possibilities would be to use the General log-linear model or the Proportional Hazards model, both also available in ALTA. For more details refer to http://www.weibull.com/AccelTestWeb/general_log_linear_relationship_chap_.htm

[thomastong]

Hello,

can anyone tell me the relationship between high temperature and low temperature during acceleration test?

Please help.
Regards

[Pantelis]

Thomas,

I am not sure I follow the question?

[lenta]

Hi
Can u help me to do this exercise?
Is required to operate at an avarage availability of no less then 92 % - optimize spare parts for this system in steady state for 2 years.
Use the poisson distribution to estimate the number of needed spare parts for this period.
----AK-----AB------AC-------E----------F
every detail has 3 periods
1) time untill failure occurs
2) repair time
3) recycle time
If u know how to deal with this problem please write me to my e mail
leniashtein@gmail.com (leniashtein@gmail.com)
And i will send you numbers (3 times for every detail )
Thank you !