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4. Use a metal sample that is typical for the expected size of metal to be detected by a given metal detector
width and height. The best samples to use are the test spheres that are shipped with the metal detector. If
ferrous, nonferrous, and nonmagnetic stainless samples are on hand, use the ferrous test sample.
5. If the package is long compared to the dimension of the metal detector, make the operate time slightly longer
than the time needed to get the package off the line. Make the delay time slightly shorter than is needed to allow
the package to get to the rejection point. This is necessary to provide compensation for two metal detection
situations:
The metal is at the leading edge of the package. In this case, the rejection device may operate slightly sooner
than when the package actually arrives at the rejection point. The longer operate time will keep the reject on
while the package is catching up to the reject point.
The metal is at the back end of the package. The package will almost be beyond the rejection point when the
reject mechanism operates.
6. If product is loose on the belt, such as cuts of meat or poultry, the reject operate time should be enough to
allow "one metal detector depth" of product to be rejected. This is the amount of product that fits in the distance
between the front edge of the metal detector and the back edge of the detector.
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