If you develop, plan or market a system, network or plant that consists of several independent subsystems, components or devices and
then you should have the availability of the entire system calculated.
This is best done at an early stage of your planning process.
SGS-TÜV Saar offers you a comprehensive range of calculation methods and calculation services. We offer reliability analyses that the market demands.
For all calculations, we draw on the many years of extensive experience of our mathematicians and engineers. It also forms the basis for EXAR, our own software application for MTBF calculations. Our experts are involved in the development of norms and standards for reliability (e.g. IEC 61709 and SN 29500).
We calculate failure rates and MTBF for electronic and electromechanical devices and components based on the IEC 61709, SN 29500, MIL - HDBK - 217F, IEC TR 62380 standards.
We offer you both the parts count method (rough forecast) and the parts stress method (detailed forecast) to calculate the MTBF.
We calculate the spare parts required.
The following statements are required to provide information on the expected reliability (failure behaviour) of electronic products:
Our services:
EXAR is a Windows software package for PCs for calculating failure rates.
The (DIN EN) IEC 61709 or the MIL - HDBK - 217 serves as the basis for this calculation for electronic components as well as for complete assemblies and devices.
When using IEC 61709, which does not specify basic failure rates, the Siemens SN 29500 method or your own failure rate values can be used for the calculation.
EXAR licensing and demo version
If you would like to carry out failure rate calculations or MTBF calculations on a larger scale yourself, we offer you our EXAR programme for purchase.
EXAR enables you to carry out availability calculations independently.
You can request a demo version of our EXAR programme for calculating availability free of charge. Contact us!
A safety-relevant system must be tested with regard to its suitability in terms of safety technology, or specifically accompanied by safety analyses during its development.
It is advisable to carry out these analyses from the early phases of a system's security life cycle in order to achieve the greatest possible benefit from them.
Possible results are:
The analysis method is selected and adapted for each project based on its suitability for achieving the best analysis results. This makes it possible to take into account the particularities of the system in the relevant phases of the security lifecycle.
Failure Mode and Effects Analysis (FMEA) is a systematic method for identifying and evaluating potential failures in a product or process. It is used to analyse the effects of errors and to develop measures to minimise risk.
There are various forms of this analysis procedure. Depending on the area of application, a basic distinction is made between three types, each of which is used in a different phase of the product life cycle.
Fault Tree Analysis (FTA) is a deductive analysis method used to identify and analyse the causes of a specific unwanted event or system failure.
Unlike FMEA, which is an inductive method, FTA starts with a top event and works backwards step by step to determine the causes of this event.
The aim of the FTA is to systematically present and analyse the complex relationships between different sources of error and their effects. This helps engineers and analysts to improve the reliability and safety of systems by identifying critical weaknesses and developing appropriate countermeasures.
We offer not only analyses on this topic, but also support and reviews, as well as training.
Markov analysis is a mathematical method used to model and analyse stochastic processes, in particular those that depend on time and where the future state of a system depends only on the current state and not on the past. This property is known as the Markov property or memorylessness.
If a system exhibits other properties, i.e. a dependence on further states, appropriate modelling measures must be taken, which can greatly increase the effort required for the analysis.
The dependency on time that can be taken into account in such an analysis offers the possibility of considering failure and repair times. Thus, the time that elapses from the discovery of a fault or failure to the repair of the corresponding element can also be modelled in a Markov model.
Markov analysis is based on the Markov process, a stochastic process with a finite number of states. The corresponding analysis tools are used to calculate such an analysis.
The HAZOP analysis is also known as the PAAG procedure. The abbreviation stands for Prognosis, Analysis, Action and Evaluation.
HAZOP analysis is a systematic and structured method for identifying and evaluating hazards and operational problems in complex processes and systems. It can be used at a very early stage of development to identify weaknesses in the system design at an early stage.
The aim is to identify potential hazards and malfunctions in a system so that appropriate changes can be made to the design based on the results of the analysis.
HAZOP analysis is a proven tool for improving safety and operational efficiency in many industrial applications.
It is an exploratory process. Possible causes and consequences of potential deviations are identified and defined by an interdisciplinary team.
This is an inductive analysis that is carried out in reverse order compared to the FTA (deductive). This method helps to identify the different paths that can develop after a triggering event and to analyse the probability and impact of these paths.
The aim of this analysis is to investigate disruptions and incidents in technical systems.
An event tree analysis can be carried out qualitatively or quantitatively:
This analysis method is represented by means of graphical symbols. These symbols form a tree structure in the course of the analysis, which then shows the resulting signal paths or effect paths. By structurally mapping these effect paths, it is possible to achieve a correct and complete modelling of the system.
A reliability block diagram is a graphical tool used to model and analyse the reliability of a system. It represents the components of a system and their reliability relationships in order to understand how the failures of individual components affect the overall reliability of the system.
It thus shows the logical links between the elements that are required to fulfil the requirements of a system. Elements that are not relevant to meeting the requirements are not shown. For example, when examining a system for the achievement of a safety objective, only the system components that are relevant to safety are examined.
The modelled blocks have the property that they can only represent an element in two states: functional or failed. The possible reasons for a failure are not shown graphically. However, various causes can be taken into account in the course of the calculation.
A completely modelled reliability block diagram makes it possible to quickly identify which system elements are necessary to fulfil the requirements and which may fail without affecting the requirements.
SGS-TÜV Saar GmbH
Benzstr. 28
D-82178 Puchheim near Munich
SGS-TÜV Saar GmbH
Joseph-von-Fraunhofer-Str. 13
D-44227 Dortmund
