Loma IQ3+ User Manual Download

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Installation

Moving metal excludes concentric rotating rollers. If they are concentric and can be guaranteed
to stay that way, then they may be classed as fixed metal.

However it is important to reiterate that they must be insulated from the conveyor at one end or
it is possible that they will cause false triggering by creating an intermittent eddy current path.

Other sources of moving metal can also include automatic reject devices, where the reject
movement is detected or supply cables that are placed too close to the detectors aperture or
not securely fixed down.

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Vibration

It is important that the detector is not subjected to excessive vibration. The conveyor must be
substantial and well supported (all feet/wheels should be touching the ground and locked) to
keep the detector stable. Electrical services must be taken through flexible and not rigid conduit.
Do not use the detector or control box as a convenient point to anchor any conduit or pipe work
whatever, whether it be rigid or flexible. Do not use the detector or conveyor as a walkway or
use the detector top to store items on.

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Belting

Conveyor belts should be plastic or polyurethane. The belt joint is best angled, preferably at
60º, 90º. Joints are not preferred unless there is no other choice, joints must be vulcanised or
heat sealed.

Clipped or sewn joints are not acceptable as product could become trapped making the belt
less hygienic or contamination could become trapped. This will affect the performance of the
detector.

Coloured belts sometimes contain oxide used as a colouring material. These are metallic in
origin and therefore can be detectable resulting in either false triggering or a reduction in
detector performance. Equally some belts have an antistatic coating that again can be
detectable; this type of belt should be avoided.

Care must be taken when fitting and joining belts to ensure that all metallic swarf and filings
have been cleared away. If any drilling of the conveyor frame is required at any time then great
care must be taken to avoid accidental contamination of the belt.

Belt tracking systems should be easily adjustable. Crowned rollers can help tracking with non
modular belt types. Always ensure that modular belt jointing pins are non-metallic.

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Skid Plate

It is important that the belt does not touch the bottom or sides of the detector aperture. The belt
must be supported through the aperture by a non-metallic material. Materials that can generate
high levels of static charge from the continuous movement across the plate surface must be
avoided. The material must be strong enough to support the weight of the product at all times.
When fitted, the plate must not protrude above the level of the rollers. It is recommended to
maintain at least a 10mm clearance between the undersides of the plate/belt to avoid contact
with the bottom of the detector aperture.

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Electrical Interference

The detector head operates at radio frequencies in the radio broadcast long wave spectrum.
The detector has been designed with a high level of immunity to mains borne interference as
well as airborne interference. If trouble is experienced, the interfering device/s should be
located and the interference suppressed at source. However if this is not possible then the
detector may have to be run at a reduced sensitivity.

It is also advised not to operate two metal detectors in close proximity that operate at the same
fundamental frequency as interaction is possible.