Relex Reliability Software

Relex product line provides an unbeatable set of tools to analyze and improve  product reliability.

Relex can be as simple or as rich as you want, since you can customize Relex by selecting only those features or tools that you need. Here is a list of all of the main features that Relex provide:

·         Relex Reliability Prediction Engine

·         Relex Reliability Prediction Analysis

·         Relex Reliability Block Diagram (RBD)

·         Relex FMEA/FMECA

·         Relex Fault Tree

·         Relex Maintainability

·         Relex Life Cycle Cost (LCC)

Reliability Prediction Engine

Reliability Prediction Engine Features

·         Supports popular electronic and mechanical reliability models including:

o        Telcordia/Bellcore TR-332

o        MIL-HDBK-217

o        Parts Count

o        NSWC-98/LE1

·         Concurrent network operation allows multiple users to access projects simultaneously

·         Global changes and trade studies provide feedback on design modifications

·         Performs reliability allocation calculations

·         Supports derating analysis per several popular standards

·         Produces visually stunning graphical outputs

Includes acclaimed Relex quality and user-friendliness

Evaluating product reliability normally begins with estimating MTBF (Mean Time Between Failures).

With the Relex menu interface, you can enter system hierarchy with associated components. The information requested varies for each component, but may include items such as power dissipation, rated voltage, resistance value, number of pins and operating temperature.  

Relex guides you easily through the entry of all data by prompting for the necessary parameters, providing a list of choices when available, and validating all entries. If the information is not readily available, you may simply leave it blank. Relex will default the applicable parameters to average values. As an added feature, Relex will even create libraries of your parts. The next time you enter your part number, Relex will automatically enter all the part data for you.  

Once the part data has been entered, perform a calculation by simply pressing the Calculate button. Relex performs calculations accurately and quickly at 25-100 parts per second, or faster, depending on your computer.

Relex Prediction
 Relex features a variety of reliability models. Choose the appropriate models that best suit your application.

The Telcordia method, formerly generated by Bell Communications Research (Bellcore), provides reliability models for commercial grade electronic components. This method also allows you to incorporate device burn-in data, unit burn-in data, data obtained from laboratory testing, as well as information from actual field testing.

MIL-HDBK-217 is the original worldwide standard for electronic reliability analysis and supports both commercial and military grade components. Both the Part Stress calculation method, which allows taking actual temperature and stress information into account, and the simpler Parts Count method, used for quick estimates and early design analyses, are supported. As an added bonus, Relex extends these calculations by supporting the mathematical models from the Telcordia specification which allow the incorporation of burn-in as well as laboratory and field data!

In addition, Relex supports the “Handbook of Reliability Prediction Procedures for Mechanical Equipment” which contains reliability models for devices such as seals, springs, solenoids, bearings, gears, splines, valves, actuators, pumps, brakes, clutches, and more.   

Prediction Data Tab

Reliability Prediction Analysis

Reliability Prediction Analysis Features

·         Includes all of the Prediction Engine features, plus comprehensive parts libraries and CAD Import/Export WizardTM

·         Supports parts from many manufacturers including:

o        Altera, AMD

o        Analog Devices

o        Cypress

o        Dallas Semiconductor

o        Harris

o        IDT, Intel

o        Microsemi, Motorola

o        Texas Instruments

o        Unitrode

o        Xilinx, and more . . .

·         Powerful Visual Basic for Applications (VBA) macros provide task automation

·         Powerful CAD Import/Export WizardTM transfers data directly from CAD systems, databases, spreadsheets, or word processors.


Library Browse Window

A major advantage of the Reliability Prediction Analysis package is access to comprehensive libraries that contain tens of thousands of parts with associated data parameters.

The Relex Integrated Circuits Library consists of over 100,000 ICs including all of the 74/54 series of digital logic devices, as well as analog/linear, microprocessors, RAMs, EEPROMs, ASICs, PALs, M38510 and SMD parts. You will also find thousands of discrete diodes, transistors, and thyristors in the Semiconductors Library, and  tens of thousands of parts in the Resistors and Capacitors Library. In addition, there is a Nonelectronic Parts Library that contains the data from the Reliability Analysis Center Document NPRD-95 with failure rates for over thirteen thousand mechanical and electro-mechanical components.

Relex also has a powerful SQL library browse and search engine that allows you to display all library parts that match a given condition. For example, you can search for all part numbers in which ‘877’ appears, or all parts that are op amps, or you can simply display all parts in all of the libraries.

The Relex Reliability Prediction Analysis package includes an extensive listing of features. You have the ability to create your own library, and using the correlation feature, you can even use your own in-house part numbers. You have access to a complete programming language with the Visual Basic for Applications (VBA) macros. You can create your own environmental and quality levels, perform reliability allocations, calculate the reliability of your product over a specific mission profile, view and edit reports using the built-in word processor, password protect your files, and you have access to the spell checker with a 100,000 word dictionary. Relex provides a powerful set of tools for your reliability needs.

Relex RBD - Reliability Block Diagram

Relex RBD Features

·         Includes powerful, intelligent Monte Carlo simulation engine

·         Supports simple series-parallel network system

·         Handles various failure and repair distributions including:

·         Supports 99 levels of undo and redo

·         Performs background calculations for efficient use of process time

·         Allows creation of visually pleasing and illustrative diagrams

·         Supports selection of images, fonts, sizing, and colors

·         Performs reliability, availability, failure rate, and MTBF calculations

·         Includes spares optimization algorithm

Diagram and Analyze Complex Redundant Systems

Relex RBD is a complete, fully featured graphical Reliability Block Diagram evaluator..

Relex RBD is the ultimate in flexibility. You can create figures of various shapes, sizes, and colors and connect them in any way you choose. You can also span diagrams across multiple pages, allowing you to analyze very large systems.

Relex supports a number of failure and repair distributions including exponential, normal, lognormal, Weibull, Rayleigh, and uniform, providing you with complete analysis capabilities.  

RBD Graphical Interface

One of the most powerful features of Relex RBD is its ability to link figures in the RBD to items in your Relex Reliability Prediction package. Simply drag a part or assembly and drop it onto the RBD. Then, as assembly or part failure rates change, the information in the RBD automatically changes! If repair information was entered in Relex Maintainability Prediction, that information will automatically be available in Relex RBD. And you can even link an entire tree from Relex Fault Tree to Relex RBD.

At the core of the Relex RBD module is the highly sophisticated Monte Carlo simulation capability. It enables  Relex RBD to handle everything from basic series/parallel systems to complex, random network configurations.

The calculation module includes a highly intelligent decision-making ability that analyzes the diagram. It actually features not one, but several methods of analyzing diagrams so that calculations are optimized based on system configuration. Relex determines the fastest and most efficient method of performing the computation. And because the Monte Carlo simulation runs as a separate process, you can continue using Relex while your calculations run in the background.

Relex RBD also has a powerful algorithm to allow you to optimize the number of spares for the elements in your designs.

With Relex RBD, the ability to analyze the most elaborate systems is at your fingertips!

Relex FMEA/FMECA - Failure Mode and Effects Analysis

Relex FMEA/FMECA Features

·         Supports automotive and SAE ARP5580 style FMEAs as well as MIL-STD-1629 FMECAs

·         Built-in flexibility provides support for design, process, and user-defined analyses

·         Automatically generates initial FMEA from assembly and part information

·         Supports multi-user environments - changes made are available to all users

·         Allows entry of up to 32K characters of information for lengthy data fields

·         Includes a supplied set of failure mode libraries for electronic and mechanical parts

·         Requires minimal storage space by automatically compressing information

·         Supports the analysis of electronic and mechanical hardware, as well as software

·         Includes spell checker with 100,000 word dictionary.


Relex FMEA Supports all Industry Standards

Relex FMEA was designed to handle your Failure Mode and Effects Analyses with unsurpassed power and flexibility. The methodology contained within Relex FMEA allows you to quickly and easily analyze the potential failure modes of your system and the resulting effects of those failures.

Various industries have their own FMEA standards, all fully supported by Relex. Aerospace and defense companies generally use either the MIL-STD-1629 FMECA standard (the C in FMECA represents the Criticality calculation) or the SAE ARP5580 FMEA standard. Automotive suppliers use SAE J1739, or the Automotive Industry Action Group (AIAG), Daimler-Chrysler, Ford, and GM FMEA methodologies. Other industries generally adopt one of these standards, sometimes customizing them to meet their own requirements. Relex supports these various standards as well as allowing you to customize them or create combinations to meet your unique needs.

Relex FMEA supports both Design and Process FMEAs. Design FMEAs are used to analyze a system design and determine how the various failure modes affect the system operation. The design may consist of both hardware and software, and the analysis can be performed at any level from the piece part up to the system. Process FMEAs, in contrast, are used to analyze how failures in the manufacturing or service process affect system operation. 

View and Edit

 Automatically Links to the Other Relex Modules

Relex FMEA may be used as either a stand-alone package or in conjunction with other Relex modules. Since all Relex products share the same database, information provided in other modules is immediately available to Relex FMEA. As you define the system hierarchy and add parts, that data is recognized in all Relex packages.

Relex FMEA also has access to failure rates calculated by the Relex Reliability Prediction module. Any time these failure rates are updated, the changes are instantly taken into account in Relex FMEA. Using Relex’s innovative Fault Tree/FMEA integration, you can generate a fault tree showing all failure modes that contribute to an end effect.

In addition, as you add components to Relex FMEA, failure modes are automatically assigned using the built-in modes libraries. This not only provides tremendous time savings, but also improves consistency throughout your analysis.

Relex FMEA is Unsurpassed Power

Relex FMEA organizes its information to minimize any redundant effort on your part by storing information you enter into a lookup table that is always available for use. Data fields can be up to 32,000 characters in length.

Relex FMEA supports fault equivalencies. You will often find that multiple failure modes all result in the same failure consequences. With Relex FMEA, you define the failure consequences once and then group these similar failure modes together.

Libraries of failure modes are also supplied with Relex FMEA. These editable libraries contain failure modes from a variety of sources and include an extensive array of electronic and mechanical parts.

Relex FMEA supports criticality assessment through risk priority numbers (RPN), criticality ranks, risk levels, criticality matrices, and failure mode probability calculations. Additionally, Relex FMEA supports exporting to LSAR compatible formats. Also included is a spell checker with a 100,000-word dictionary, password protection, and a powerful Visual Basic for Applications (VBA) macro programming language.

Relex FMEA has taken Failure Mode and Effects Analyses to new heights. The comprehensive analysis capabilities and unmatched flexibility make Relex FMEA a necessary part of your analysis tool set.

Relex Criticality Matrix

Relex Fault Tree

Relex Fault Tree Features


Analyze Your System Safety Using Relex Fault Tree

With the Relex Fault Tree package, you can conveniently create complete fault trees and perform fast and accurate calculations. 

One of the primary benefits of using Relex Fault Tree is that it is automatically linked with the rest of the Relex product line. You can drag and drop failure modes from Relex FMEA, or individual components and assemblies from Relex Reliability Prediction, into your fault tree. You can also drag a fault tree and make it a part of an RBD. Because of linking, any information modified in one Relex module is automatically  updated in associated modules. 

In addition, Relex can automatically generate a complete fault tree from your FMEA. This allows you to visually determine which failure modes contribute to an end effect.

Relex Fault Tree Versatility

Relex Fault Tree provides both a standard graphical view as well as a compact table view of your fault trees.  This allows you to see the visual representation as well as efficiently edit any of the data.

One of the many unique capabilities of Relex Fault Tree is the simultaneous display of the fault tree in a standard view as well as a table view. The expandable/collapsible table view facilitates the viewing and editing of the properties of the various gates and events, as well as editing large trees.

Relex Fault Tree supports many different types of gates and events. Gate types include OR, AND, NOR, NAND, NOT, XOR, Voting (k/n), Remarks, Inhibit, and Transfer. In addition, Priority AND gates, where the inputs are order dependent, are supported with the use of Markov modeling. Event types include Basic, House, and Undeveloped. Event data can consist of failure and/or repair data, constant probability data, failures with periodic inspections, and more. Relex is also compatible with common cause failures using the Beta, MGL, Alpha, and BFR models. Additionally, support is provided for repeated events.

Relex Fault Tree includes a host of powerful calculations for both qualitative and quantitative analyses. The Minimal Cut Set (MCS) engine quickly determines the minimal cut sets and provides the capability to view them on your fault tree diagram. You can calculate the unreliability, unavailability, frequency of failures, and number of failures. You can compare the relative importance of various events using the Birnbaum, Criticality, and Fussell-Vesely methods. And, you can perform time-dependent analyses and get an array of scientific graphs of your results.

If your fault tree is very large, you may wish to approximate the results of your analysis in order to improve calculation speed without adversely affecting accuracy. You achieve this by limiting all cut sets below a certain probability or using the cut set summation, cross product, or Esary Proschan methods.

Relex Maintainability Prediction

Relex Maintainability Prediction Features


Relex Maintainability Prediction provides you with a solid framework for performing maintainability analyses. You enter the hierarchy of your system using Relex’s system tree and define all of the replaceable items with their associated repair times. Relex Maintainability Prediction then calculates many maintenance parameters including the Mean Time to Repair (MTTR), Mean Maintenance Manhours per Repair (MMH/Repair), and the Percent Isolation to a Single Replaceable Item, as well as many others.  

Maintainability Information

Relex Maintainability Prediction is based on the accepted standard for maintainability predictions, MIL-HDBK-472 Procedures 2, 5A, and 5B. Relex Maintainability Prediction organizes the process of performing your analyses by incorporating these methodologies in an easy-to-use, functional framework.

You begin your analysis by defining your basic maintenance tasks with their repair times, If you wish, you may group these basic tasks together into larger, more complex super tasks. For example, the super task of replacing a printed circuit board may consist of turning off the power, opening a box by taking out several screws, removing the board, setting a new board in place, replacing screws, closing the box, and restoring power. These smaller tasks need only to be defined one time and then can be reused in defining super tasks.

At this point, you have the option of defining your Fault Detection and Isolation (FD&I) Outputs and linking them to your tasks.  Then, when you are ready to define the characteristics of the replaceable items, you can enter repair tasks directly or you can enter the FD&I Outputs with the replaceable items.

There is a seamless integration between Relex Maintainability Prediction and the other Relex modules. There is one system tree that all of the Relex products share, so a change to the system tree in one module affects all other Relex products. The same idea applies to individual components. A component need only be entered one time for all Relex modules to recognize it. So, as you add assemblies to the system tree or components to assemblies, all Relex modules have access to them and their data. For example, Relex Maintainability Prediction automatically has access to the failure rate of a part based on the calculated information from Relex Reliability Prediction. 

Supported Maintenance Calculations

Relex Maintainability Prediction supports a host of powerful calculations.

Once you have defined your system, Relex Maintainability Prediction can perform various calculations including Mean Time to Repair, Percent Isolation to a Single Replaceable Item, Mean Maintenance Manhours per Repair, Mean Maintenance Manhours per Operating Hour, Maximum Corrective Maintenance Time, and more.

Relex Maintainability Prediction also has the ability to import and export data using the CAD Import/Export WizardTM including exporting to a MIL-STD-1388 2B LSAR compatible format.

A task library taken directly from MIL-HDBK-472 is included with Relex Maintainability Prediction. You can append to the supplied task library or create any number of your own libraries.


Relex Life Cycle Cost

Relex Life Cycle Cost Features

Relex Life Cycle Cost (LCC) is a powerful tool that calculates the cost of your product over its lifetime. You may include many different types of costs such as design, production, warranty and repair, and disposal. Relex LCC provides support for parametric, analogy, bottoms-up, and direct cost analysis types.

By taking inflation factors and different designs into account, you can easily perform a trade-off study of various alternatives over your equipment’s lifetime. For example, you may wish to compare an item with a higher initial cost and lower repair costs to an item with a lower initial cost and higher repair costs. You may also want to compare the cost of upgrading existing equipment versus procuring new equipment. Relex LCC provides these capabilities and much more!

Relex LCC - Ease of Use
Using Relex LCC’s Cost Breakdown Structure (CBS) tree, you may take any cost into account in your analysis. You choose the elements that affect your overall cost and then break those elements down into their respective sub-elements. You can use the built-in equation editor to assign calculation properties to all elements in your CBS tree.

With Relex LCC you can define a wide range of cost variables, including alternative and time dependent variables. Calculated cost information includes total lifetime cost and can also include sensitivity calculations and Net Present Value (NPV) computations.

LCC Time Intervals

Because certain costs, like warranty and repair costs, depend on the failure and repair rates of your equipment, it is helpful to be able to use this information in your cost analysis. Relex LCC provides you with the ability to create these links. You may include items such as failure rate, MTBF, MTTR, reliability, availability, and number of spares computed with other Relex modules.

Visual Report Designer

The Report Designer, built into every Relex software package, provides unlimited flexibility. Its familiar drag and drop interface allows you to design customized reports in minutes. You select the information that you want to appear on the report and you place the information wherever you desire. You can select from all of the Relex data fields and you can type in your own text.

You can also sort your report by parameters such as Part Number, Reference Designator, Failure Mode, and Failure Rate. You can filter your report to include only specific items such as parts with a zero failure rate, overstressed parts, parts using defaulted data, or only critical failure modes.

With Relex you can design any number of your own report formats, allowing you to create custom reports for any need. In fact, if you have several Relex products such as the Relex Reliability Prediction Software and the Relex FMECA Software, you can design composite reports that combine information from each. Relex also comes supplied with many standard reports to output items such as pi factors, overstressed parts, system tree summary, failure mode and effects analysis, maintainability data, and much, much more.

You can add page headers and footers to your report. You can also generate reports with varying levels of detail. For example, you can create a report which includes system level information, component level information, or a combination of the two.

Presentation Graphics

Graphical capabilities enable you to quickly and easily analyze your design, and can significantly enhance your reports and presentations.

You can create a wide array of graph combinations with the Relex Graphics Module. Some examples of the plots you can specify include: Failure Rate vs. Temperature, Reliability vs. Time, MTBF vs. Temperature, MTBF vs. Environment, Failure Rate vs. Stress Level, Percent of Failure Rate vs. Environment, simple comparison charts, Pareto Charts, and more.

You can also specify the type of graph for these plots, including line graphs, bar charts, pie charts, area graphs, stacked bar graphs, and scatter plots. And, you can graph your entire system, individual components, or parts of your system.