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INTERMITTENT FALSE TRIPS
Observe the surroundings.
When the detector trips, try to figure out what could be causing it.
Look for two pieces of metal making intermittent contact in the vicinity of the metal detector.
Look for starting/stopping of nearby machinery.
Verify that the electrical ground to the detector is making solid connection.
Check for static electricity around the metal detector. Control static by using an antistatic spray or by grounding
the slider bed and conveyor belt.
Check the conveyor belt for a build-up of grease or grime, or for embedded metal. Such metal can be located by
running the belt without product and marking the belt each time the detector triggers. If the marks appear in the
same spot, loosen the belt and thoroughly clean the top and bottom of the belt.
If the detector has a remote mounted control cabinet, make sure that the connecting cable is securely fastened to
prevent movement.
Check to see if the rejection device is binding when it moves, causing excessive vibration.
CONSTANT FALSE TRIPS
Check to make sure that the product being inspected has not changed in any way. If a product changes in
moisture, temperature, or mass it will change the product signature and the current settings could fall outside of
the allowable margins, causing false triggers. If this occurs, return to the set-up portion of the manual and reset
the detector for the new product parameters, or re-learn the product.
Check to make sure that there are no devices in the area that are transmitters of radio frequencies. They will
interfere with the detector and cause false triggers.
Check for metal in the metal-free zone.
Call the factory for support.
CONVEYOR WILL NOT START
Verify that there is correct power supplied to the conveyor motor starter.
If the detector is used to stop the conveyor, make sure that the detector has been reset. Also check that you are
using the correct outputs and that they are configured as normally closed.
Check that the overload relay in the motor starter has not been tripped. If the overload continues to trip, increase
the current setting slightly.
CAUTION
: If the setting is too high, it will not protect the motor in the event of an
overload.
