Loma IQ3, User Manual

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Operating Instructions
Setting reject times is best done by passing the product, contaminated by a detectable metal
test sample, through the machine and the adjusting the delay (time or distance from detect to
reject) and dwell (time or distance the reject device operates for) to obtain a clean removal of
the contaminated product from the transport into the reject collection device. All units of time
are in seconds.
For systems where a Product Registration Photo-eye is not being used, the reject delay time
is the time in seconds between when a contaminant is detected in a product to when the
reject device is activated to remove it from the production line.
The position of the contaminant within the product (length) will directly affect the reject delay.
You must therefore make allowances in the delay time to ensure that wherever the
contaminant is located in the product a clean rejection is achieved.
For systems where a Product Registration Photo-eye is used, reject delay timing is always
timed from when the leading edge of the product activates the photo-eye regardless of where
in the product the metal contamination is situated.
When using variable speed systems, the delay is timed by distance which is entered in metres
in the Reject delay field. See the
Menus > Service > Configuration > System menu to view
the available speed mode options.
Enter the reject delay time in seconds, or for variable speed systems, enter the distance in
metres.
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Reject dwell
Reject dwell is the time or distance that the reject device operates for to remove a
contaminated product from the conveyor belt and into the reject collection device. It must
therefore be set to ensure clean removal of the contaminated product.
Please read through the information contained in the Reject delay section above for further
guidance. Reject timings may also be set in the
Menus > Service > Reject > Set Up menu.
Enter the reject dwell time in seconds, or for variable speed systems, enter the distance in
metres.
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PVS Test
Select this option if you are using the Performance Validation System to carry out product
testing at specific times and have configured this in the
Menus > Set Up > PV Test Set Up
menu. You can also access the PVS Log to view the test details.
Learning Products
An essential part of inspecting products is to set up the metal detector parameters specifically for
each product to optimise the detectors performance for each one. Loma metal detectors provide a
Learn feature which automates this process.
The Learn settings and the process to be followed is defined in the Menus > Learn > Set Up and
Menus > Service > Configuration > Learn Limits menus.
Note that the Menus > Learn > Set Up menu is only available if the Set Up Learn option has been
enabled in the Menus > Service > Options menu.
The metal detector provides three alternative Learn processes:
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Full Learn
This process must be carried out initially on all products as it automatically configures and
populates the system settings and parameters based on effect of the product on the
electromagnetic field as the product passes through the inspection aperture.
The product samples used for the Learn process must be free of metal contaminants and fully
representative of the normal products to be inspected.
Following a Full Learn, any manual adjustment to the settings for a product can be accessed
through the
Menus > Learn > Set Up menu. See the Full Learn section for further details.
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