Understanding IPC-9850

After accuracy and placement quality (defects per million), a pick-and-place machine’s output is perhaps its most important parameter. It determines the number of boards that can come from a line, and thus the line’s return on investment.

The output of a pick-and-place machine depends strongly on the application, though. The number of components actually placed per hour will normally depend on the board size, the type of components placed, and even the accuracy needed to place them. Different manufacturers used to specify the outputs under their own conditions, and the temptation was, of course, to show the manufacturer’s own machine in the best light. That was misleading for purchasers, since the figure was not necessarily related to the number of components their lines would actually place.

To clarify matters, an IPC SMEMA committee in 2002 wrote IPC-9850, Surface Mount Placement Equipment Characterization. This standard establishes measurement procedures for specifying, evaluating and verifying surface mount placement equipment. The standard details how measurements must be made, and emphasizes consistency as the best way to compare them.

IPC-9850 has become a basic industry reference, but doesn’t tell the whole story. Several pick-and-place machine manufacturers, for example, currently claim the industry’s fastest placement speeds on the basis of the IPC reference speed. This usually comes, however, from selecting the most favorable IPC-9850 conditions. Speeds can be measured for a simple matrix of one type of component, for example, with “gang pick” operations, giving artificially high figures. These theoretical maximum speeds do not necessarily relate to the actual output in a particular application.

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