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Relex Reliability Prediction
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Relex Reliability Prediction
provides the user-friendly and flexible Reliability Prediction
Engine that makes reliability predictions both fast and easy.
Use Relex to pinpoint problem areas, analyze design changes,
and enhance and improve the overall reliability of your product.
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What is a Reliability
Prediction? A reliability prediction is simply the analysis of
parts and components in an effort to predict and calculate the rate
at which an item will fail. A reliability prediction is one of the
most common forms of reliability analyses for calculating failure
rate and MTBF.
What is MTBF? There are
many forms of the MTBF definition. In general, MTBF (Mean Time Between
Failures) is the mean value of the lengths of time between consecutive
failures, under stated conditions, for a stated period in the life
of a functional unit. A more simplified MTBF definition for Reliability
Predictions can be stated as the average time (usually expressed in
hours) that a component works without failure.
A reliability prediction is usually based on an
established model. Common models are MIL-HDBK-217
or Telcordia for electronic components and NSWC-98/LE1 for mechanical
components. These models provide procedures for calculating failure rates
for components. Relex Prediction has all of the major prediction models
developed for conducting a series reliability calculation on your systm.
Calculate MTBFs and failure rates by gathering information regarding components and calculating based on standard equations. The equations take into account various stress parameters of the components, and may include data such as device temperature, operating voltage, rated voltage, and power stress ratios.
In order to do a reliability prediction, you must gather information about the components in your system, then use this data in mathematical equations to perform failure rate or MTBF calculations. The prediction models employed to calculate failure rate do not contain listings of failure rate values for devices, but include equations for calculating failure rates of various devices. The complexity and required parameters of these equations varies depending on device type. Relex automates this entire procedure by asking for the necessary parameters, and quickly and accurately performs the series reliability calculation to compute the failure rate.
Relex also offers a comprehensive set of Parts
Libraries which include data parameters on thousands of devices. This
means that you simply need to enter a part number and Relex will automatically
fill in the requested information. You then just need to enter the "operating"
parameters of your components, such as operating temperature to perform
a reliability predictions, failure rate calculations, and MTBF calculations.
Why
do I need to perform a reliability prediction? MTBF (Mean Time Between Failures) for an existing product can be found by studying field failure data. For a new product however, or if significant changes are made to the design, it may be required to estimate or calculate MTBF before any field data is available. In some cases failure rates for previous products can be used if changes to a design are unlikely to affect reliability. In the case of a new or significantly changed design, an accepted technique is to estimate reliability using a recognized model.
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