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Testing Boards Longer Than 24inches

Testing Boards Longer Than 24inches in the Series II, 2L, 3, and 5000 5DX systems.

The current 5DX specifications support panels (boards) up to 18inches wide and 24inches long. Customers who need to test boards that exceed these dimensions can utilize this procedure to test boards longer than the advertised 24inches, but no wider than 18inches (hereafter referred to as "extra-long boards").

The width restriction is a fundamental constraint of the auto width adjustment rails. They cannot open further than 18inches. The 5DX stage can accept boards up to approximately 27inches in length, depending on the presence of components which extend beyond the board's stern edge. The specification remains at 24inches for length for 2 reasons. The first is that the stage cannot move far enough in the Y-axis to bring outlying components under the X-ray tube. The second is the increased likelihood of extra-long boards interfering with the outer barrier and associated hardware.

Testing Boards Longer Than 24inches in the Series II, 2L, 3, and 5000 5DX systems.

NOTE: Verify that the board can be loaded without being damaged before proceeding.

Testing these boards exploits the 3-inch margin built into the stage's Y-axis. At the heart of the procedure is the division of the panel program. Though the intention is similar, this should not be confused with standard long panel division, as that process maintains a single panel program. Extra-long boards require 2 panel programs that are tested independently. One program contains only those components that can be conventionally tested; in other words, those located within the standard testable length. A second panel program includes just the components in and/or near the region beyond the 24inch limit. The user can determine the exact proportions of the 2 programs. The division can be achieved by duplicating the original panel program and removing the appropriate components from the test in the two resulting programs .

During testing, the board will need to be unloaded and rotated 180 degrees in order for components beyond the 24inch limit to be inspected. Additionally, rotation of the component and pad locations will therefore need to be incorporated into the second panel program.

In light of these considerations, an extra-long board requires a modified test procedure. This would include the following steps:

  1. Load first panel program
  2. Load panel
  3. Test appropriate components
  4. Unload panel
  5. Load second panel program
  6. Rotate panel 180 degrees and reload
  7. Test remaining components