Doc. Ref.No: Q875-0143/ENG
Issue 2
Met 30+ Operating Manual
12/01/10
7. SAMPLE TEST
As high-resolution detectors are sensitive devices that may drift with changes in
environment, it is prudent to have an organised procedure for physically checking the
system. A known test sample, shipped with each detector, should be inserted into an
identified fresh sample of the product and passed through the detector. It should be
detected and accurately rejected. This will ensure that the detector timing devices
and auto reject mechanism are functioning correctly. If specifications include ferrous
and stainless, both should be used for the test. On a long product, the metal test
piece should be positioned at the leading and then the trailing edge to ensure the
product will be rejected under all circumstances.
The Lock metal detector's provide the 'Sample test reminder' facility to ensure
regular testing takes place, while the printer facility provides a hard record of the
frequency and details of the test.
This document describes the operation of the 'Sample test reminder'; details of the
printer operation are given in the guide to using printers with Lock Inspection
Systems metal detectors.
7.1 Operation
The operation of the sample test reminder facility is shown in the ‘Sample Test
Flowchart’ Section. This shows the messages given on the detector's display, the
lights on the tower (if fitted), the state of the detector and the events/operator
activities to change from one state to another.
The ‘Sample Test Flowchart’ shows the normal state of the detector, i.e. the product
under test and bargraph are on the display, the green lamp is on indicating normal
operation.
When the sample time elapses (reference #2), normal operation continues but the
display changes to "SAMPLE TEST DUE <SELECT>" and the orange lamp turns on.
The detector will continuing functioning normally until either the SELECT key is
pressed or the 20 minute timeout elapses (Adjustable by Lock Engineers). If the
timeout timer elapses then the red lamp is turned on, and the belt will stop, provided
that the fault relay has been configured to stop the conveyor (see the installation
manual).
In either case (reference #3), "Do sample test <SELECT>” is displayed. The
detector cannot now be used until the sample test is executed successfully.
If the SELECT key is pressed (reference #4) the operator is asked to enter a P.I.N.
number by the message "Enter P.I.N.:". This number is recorded in the metal
detection sensitivity test report (see the printer guide), which also provides evidence
of the time when the test was run and the phase and size of the test sample
detected.
File Name: Q875-0143 ENG Iss2 Met30+ Operating.doc
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