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Entry type: FAQ Entry ID: 109747636, Entry date: 05/31/2017

Assessment of the effect of wear and tear on the service life of electromechanical devices

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This entry contains information on the effect of wear and tear on the service life of electromechanical devices.


What must be observed if electromechanical components reach the maximum number of switching cycles before the end of their service life?


The operating time of an electromechanical device is limited to T10D, the mean time until 10% of the components have suffered a dangerous failure. A constant component failure rate can only be assumed during the calculated operating time.

If the maximum number of switching cycles (operating time) is reached before the end of the service life (normally 20 years) of the electromechanical component, it must be replaced. The service life of the replacement component begins from this time, and with it the component’s maximum number of switching cycles (operating time).

The PFH/PFD value of the application, which was determined on the basis of the PFH/PFD values documented for the individual components, is not affected by this and remains the same as before, if the component has been replaced.

 Registrierung notwendig  Mission-time_operating-time_EN.pdf (994,4 KB)

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