Loma IQ3+, User Manual

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The User Interface
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Leave the field blank if this test piece should not be used as part of the PV test.
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St. Steel test
Tap in the S. steel test field to display the pop-up numeric keypad screen and enter the
stainless steel (normally 304 annealed) test piece size in mm to be used for PV testing.
Leave the field blank if this test piece should not be used as part of the PV test.
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False Threshold
The false threshold value is used to detect when metal test pieces are larger in size than
those specified by the PV test.
If this threshold is exceeded at any time during a test it does not count towards a
successful test. All PV test samples must be passed correctly for the PV test to be
successful.
To ensure the correct false threshold value is entered, note the signal values obtained
whilst passing all the test pieces used. The ideal false threshold value is the largest signal
obtained plus a small margin added for error.
If you are not sure what margin for error to apply, test with the next size up test pieces,
note the values obtained and then set the threshold about midway between the largest
signal value from the test pieces to be used and the largest signal value from the next size
up.
Note that PVS test pieces are not recorded in the Contaminants Log or included within the
reject count.
Tap in the False threshold field to display the pop-up numeric keypad screen and enter the
threshold value to be used for PV testing.
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Tracker
The Tracking feature allows the detector to automatically adjust the working threshold for a
product between Maximum and Minimum limits set in this screen, to enable the sensitivity of the
detector to be optimised in situations where the product signal drifts up and down with changes
in product effect. See the Setting Up Product Signal Tracking section for further details.
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Min limit
This field is used to set the lowest product signal level to be used by the Tracker feature
when making automatic threshold adjustments. The value defaults to the working
threshold calculated by the detector during the product Learn process and cannot be set
any lower than this value.
If you wish to increase the Min limit value, tap in the field to display the pop-up numeric
keypad screen and enter the required value.
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Max limit
This field is used to set the highest product signal level to be used by the Tracker feature
when making automatic threshold adjustments. The value defaults to twice the working
threshold calculated by the detector during the product Learn process. The value cannot
be set less than the Minimum limit but may be increased up to the value of your choice.
It is strongly advised to set this value to just greater than the typical amount by which the
product signal is expected to change. All signals that exceed this value will be rejected.
If you wish to change the Max limit value, tap in the field to display the pop-up numeric
keypad screen and enter the required value.