Calculate reliability before failures occur.
In the area of electronic components in particular, it is possible to carry out preventive failure rate calculations. Standardized failure data catalogs such as the Siemens standard SN 29500 are used for this.
As electronic components are highly standardized in contrast to mechanical components, system failure rates can be calculated preventively. However, these calculated values only apply within the so-called useful lifetime of a system.
Parts count and parts stress method
When calculating the system failure rate, a distinction is made between two basic methods:
-
Parts count method
- Determines how many components of each type are contained in the system.
- Only uses reference failure rates to determine the system failure rate.
- Considered critical because the actual failure rates of electronic components often vary exponentially with temperature.
-
Parts stress method
- Extends the calculation to include stress factors such as temperature, current and voltage.
- Component failure rates are derived from a reference failure rate and corrected for the actual load.
- To calculate the stress factors, load profiles of the components are required, which must be determined beforehand.
- This method is more complex, but provides realistic failure rate values, as required for warranty and spare parts forecasts, for example.
Our services
- Determination of system failure rates for electronic systems in accordance with Siemens standard SN 29500 and Military Handbook 217F
- Support with the definition of component load profiles
In combination with other methods
Preventive failure rate analysis is closely linked to electronics reliability as well as the RAM/LCC and reliability testing methods. Together, these approaches enable a well-founded forecast of system reliability – from development to simulation and application evaluation.
