IEC 62005-2 pdf download

IEC 62005-2 pdf download Reliability of fibre optic interconnecting devices and passive components – Part 2: Quantitative assessment of reliability based on accelerated ageing tests – Temperature and humidity; steady state
1 Scope
This part of IEC 62005 provides a basis for defining reliability tests for passive optical components. It provides advice on life testing procedures, the calculation of failure rates and the presentation of results. In addition to such general guidance, a worked example illustrates the method of calculating the instantaneous failure rate for a device during its service lifetime, based on accelerated life tests.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of IEC 62005. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this part of IEC 62005 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of IEC and ISO maintain registers of currently valid International Standards. IEC 62005-4:1 999, Reliability of fibre optic interconnecting devices and passive components – Part 4: Product screening
3 Guidance on testing for wear out failures
3.1 Failure distribution Experience has shown that a log-normal distribution of times to failure can often be assumed to apply for wear-out failures of passive optical devices. That is to say that the log to the base e of the times to failure will have a normal (Gaussian) distribution. The dispersion parameter, σ, is the standard deviation of the logarithm to the base e of the times to failure. The log- normal distribution is the basis of the calculations shown in this standard.
The probability distribution function for a log-normal distribution is given by equation (1 ).
In some cases, a Weibull distribution may provide a better representation of the failure distribution. The principles outlined in this clause are still valid, but the calculation involved in determining wear-out failure rates will be different. Where experimental results indicate that there is more than one significant failure mechanism, the median time to failure and dispersion should be reported in each case.
Information shall be provided to justify extrapolation models and activation energies used in reliability predictions. Field feedback shall be collated to support the basis for the accelerated ageing tests. Where feedback suggests that failure rates are very different to those predicted, failure analysis shall be carried out to allow the accelerated ageing programme to be modified appropriately.