Output Test Fixture

See also the following reports describing expl output testing fixtures procedures ... 

Heating to 350 K increased the output of all three gauges near the cone apex. The hoop strain at the top (gauge 4) may have been very small due to the constraint of the test fixture. Comparison of gauges 1 and 2 indicates that there was a greater strain on the exterior than on the interior. 

A few boards are tested, and, if results appear reasonable, the program is considered valid. The key drawback of the method is that self-learned test programs determine that all the boards are the same, not that they are good. Moreover, for economic fabrication of the test fixture, it is necessary to process product data anyway thus we may as well have output a data-driven test program. With virtually 100 percent of board designs being CAD-driven, there is little motivation to use self-learning today. 

Fixture file outputs The completed CNC files for fixture drilling and fabrication can now be created and the test fixture prepared. 

The plot shows the response of cells to short circuit where the external circuit resistance is less than 100 mS2. The cell current peaks within less than a minute and the temperature maximum occurs a few minutes later. The current often exhibits a plateau with a slow rise, which is due to increased conductivity of the cell at elevated temperature. Cells typically can withstand an external short circuit, since thermal output is small and the cell is in contact with the test fixture. Thermal management will dictate whether response of cells will be benign, as in this test, or exhibit thermal mnaway. Large cells (i.e., over 10 Ah), cells that can sustain very large short-circuit currents, cells that have higher internal resistance, and cells with low inherent thermal stability are more prone to exhibit thermal runaway. 

Define Wiring Intetfaces Based on the Previous Step At this point you should be able to prepare an interface control document (ICD) that defines the wiring interface on the test set for each bias, clock, and output signal. This document generally defines the interface from the test fixture connectors to the test set connectors. 

Reconnect cables to the dewar or device test fixture. Look at one of the FPA outputs. Is there any signal present Even if the output is not changing, is it at an expected output voltage ... 

Knowledge of how the fixture has taken hold of the product is essential to determining which system test points to employ in performing specific measurements. Thus, the same software system generally outputs both the final test program and the fixture drilling/loading information. 

Fixture data, test program, and repair file output, and subsequent apphcation of the data. 

Ideal fixture software readily accepts the product data, analyzes the data, recommends an optimal fixture design including aU fabrication details, and outputs computerized numerical control (CNC) files for fixture fabrication, material requirements, special procedures required, and a test program in the proper format for the selected test system(s). 

Of course, a few systems still use wired fixtures, and here the output wiU be a set of drill files, a wire list, and the test program. The balance of this discussion focuses on tilt pin... 

The component IL test indicates the same relative difference between the EPDM and TPV sections [Figure 9]. A fixture mimicking the seal environment was used in the Kolano and Saha Engineers, Inc. test chamber [Figure 3] to compare the insertion loss (IL) characteristics of the seals on a component level. Seal lengths of 400 mm were used with the ends securely sealed with clay. The effects of holes were included consistently between specimens. Outputs were measured from 25 to 10,000 Hz and presented in 1/3 octaves. 

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