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Q1. |
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How can we best determine the basic sensitivity? |
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A1. |
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Check the sensitivity by detecting an Fe and SUS
testpiece attached to the product. When the product effect is large, it
is necessary to measure the basic sensitivity that takes the product
temperature and shape randomness into consideration as well as low basic
sensitivity. |
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Q2. |
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Can you explain the classification of wet and dry
products? |
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A2. |
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There is no clear division point but water content is a
practical method.
Dry products are items like snacks foods, candies, wheat flour, and
completely frozen items.
Wet products are items like vegetables, ham, sausage, pickles and raw
meats. |
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Q3. |
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How can we best avoid operation errors caused by floor
vibration? |
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A3. |
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It is best to install metal detectors in locations with
no floor vibration but if this is not possible, use the metal detector
with lower basic sensitivity. |
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Q4. |
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How can we prevent mis-detection of metal contaminants? |
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A4. |
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You can reduce the misdetection rate by managing the
basic sensitivity for each product and by performing careful operation
checks at the daily inspection. |
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Q5. |
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At shipping inspection we get OK but then at acceptance
inspection we get NG! |
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A5. |
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The basic reason is the difference in detection
sensitivity with a larger detection head. The shipper often performs
inspection with a large detection head while the buyer splits the
delivered product into smaller parts and inspects with a smaller
detection head. It is very important to use a metal detector with the
smallest possible entrance (opening) matching the size of the product. |
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Q6. |
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We want to be able to detect lead shot, bullets, and
hypodermic needles in lumps of meat! |
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A6. |
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A block of meat is very wide and thick and detection may
not be possible even with a large detection head. In this case, to
detect small metal contaminants, it would be best to cut the meat into
smaller pieces and then perform detection with a smaller head. |
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Q7. |
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We want to be able to detect pieces of metal brushes and
metal mesh! |
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A7. |
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It can be very difficult to detect needle like metal
contaminants from metal brushes and metal mesh. Even if the pieces are
long, if they are very small diameter, they may not be detected. |
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Q8. |
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Why does detection sensitivity change with temperature
in frozen products? |
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A8. |
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Compared to a perfectly frozen product, the effect of
water and salt content on detection sensitivity is larger in thawing or
defrosted products, so the detection sensitivity is lower. |
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Q9. |
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Can you detect burned and rusted metals? |
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A9. |
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Yes. However, the detection sensitivity varies according
to the shape and orientation of the contaminant. In addition, very small
particles may not be detected. |
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Q10. |
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Why does the bar graph display continue to move even
when products are not being fed through the detector? |
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A10. |
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A metal detector detects metal contaminants by detecting
very small changes in the magnetic field. Consequently, if there are
moving metal objects or machinery that generates a strong magnetic field
nearby, they may cause changes in the magnetic field and be detected. In
addition, a dirty conveyor belt can also cause field fluctuations. |
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Q11. |
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Can operators wear rings and wristwatches, etc., while
working? |
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A11. |
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Metal rings and wristwatches, etc., can have an effect
on magnetic fields and be detected by a metal detector.
Operators should remove rings and wristwatches before starting work.
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Q12. |
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Can products in transparent bottles be detected? |
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A12. |
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In the case of completely transparent bottles, the
photocell may miss the product. In this case, consult Anritsu for
possible solutions. |
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Q13. |
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What cautions should be noted when feeding bulk
products? |
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A13. |
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When a rejector is connected, it is necessary to set a
sufficient rejector hold time (rejector operation time).
When the metal detector operation is set to stop at metal detection,
remove all the bulk product from the conveyor belt before restarting. |
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Q14. |
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What is the warm-up time after power-on? |
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A14. |
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To ensure accurate detection, the metal detector should
be allowed to warm-up for 30 minutes or more after power-on.
The metal detector should be reset when the room temperature changes
markedly, especially in the morning. |
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Q15. |
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What precautions are needed at cleaning? |
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A15. |
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Any dirt and product particles must be cleaned off
frequently from the detector head opening and conveyor belt gaps using a
neutral detergent and a soft plastic brush and cloth. Do not use
thinners, toluene or metal brushes, etc. In addition, clean the main
unit with hot water at less than 40 degrees Centigrade (in accordance
with waterproofing specifications). |
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Q16. |
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We want to keep a record of the detection operation. |
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A16. |
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Use the optional printer.
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Q17. |
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We want to install a metal detector and checkweigher but
the space is too small. |
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A17. |
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Anritsu also has spacesaving checkweigher models with an
integrated metal detector. |
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Q18. |
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Can the metal detector detect non-metallic contaminants? |
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A18. |
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No. To detect non-metallic contaminants like bone,
shell, stones, glass, etc., you should use Anritsu's X-ray Inspection
System. |
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