Lambda Predict Example 1

In this example, you will use Lambda Predict to perform a standards based reliability prediction for the following configuration (a subassembly that consists of three capacitors):

	System	Block	Capacitor	Capacitor	Capacitor
Part Number		PS1	CK 33PF	CQ-10NF	0805 COG
Name		10	10.1	10.2	10.3
Analyst		A. Designer
Circuit Ref			C1	C6-10	C3-C5
Description	ABC Computer System Model ABC/XT Pentium-based Microcomputer	Power Supply 110/240 V AC Supply, 5V/12V DC Output	CAPACITOR, FIXED, CK, 33PF	CAPACITOR, FIXED, POLYESTER, 10nF	CAPACITOR, FIXED, CERAMIC CHIP, 220 pF
Notes				These capacitors are rated at 24 volts and being used at 20. If this causes a problem upgrade to 40V devices.

Data Entry
Create a new project by clicking Create a New Project in the What do you want to do? window that may appear at startup, selecting New Project from the File menu or click the New Project icon in the MDI toolbar. In the Create New Project window, click Select standard and then select MIL-HDBK-217F, as shown next.

(Note: Although this example is presented using the MIL-217 standard, the procedures for using all other standards are similar; if the MIL-217 standard is not available on your computer, you can use any available standard. The steps in the example are the same but the results may be different.)

To add a block to the system, right-click the system in the System panel and select Add then Add Block from the shortcut menu. To add components to the block, right-click the block and select Add then Add Component from the shortcut menu. The Select Category window will appear, as shown next.

Select Capacitor from the list and either double-click it or click OK to add it to the block. To add the remaining two capacitors, you can either repeat this process or copy the existing capacitor and paste it to the block using the Copy and Paste commands in the shortcut menu. The final configuration will look like the one shown next.

Enter the information specific to each part by clicking on the part and entering the data in the Data panel. The Data panel Dialog view and Grid view for the second capacitor are shown next.

Results
To view calculated results for a particular item in the Pi/Rate window, select the item in the system configuration and select Analyze from the Tools menu or click the Analyze icon. The window shown next displays results for Capacitor 10.1.

To view results in the Results Viewer, select the item in the system configuration and open the Results Viewer by selecting Results from the Tools menu. The Results Viewer shown next displays results for the block in this system. The first panel displays the Failure Rate, MTBF, Unavailability and Contribution values that have been calculated for the selected block. The second panel displays the Failure Rate values that have been calculated for the selected block and for the components in the next level of the system configuration hierarchy. The third panel displays the Pi Factors for the components in the next level.

The next step is to plot the system data. Select the MIL-217 system in the System panel and then select Plots from the Tools menu. By default, the last plot type that was selected will automatically be plotted when you open the Plot Viewer. For this example, select Failure Rate vs Temperature from the Plot Type drop-down menu that appears in the Control Panel on the right side of the Plot Viewer. If the Auto Refresh option on the Control Panel is not selected, you will have to click the Refresh Plot icon to refresh the plot with the new plot type. Your plot will look like the one shown next.

Once you have closed the Plot viewer, select Save Project from the File menu and save the project as First Steps.LPP.

Close the project by selecting Close Project from the File menu, leaving the MDI empty. This project will be used again in Example 2.

Lambda Predict Examples