You’re probably familiar with metal detectors, those long metal rods generally used at airport gates and entrances to secure establishments. When you’re not familiar with them, you tend to think that these are the only uses for this equipment. However, metal detectors have multiple applications and are used in many different fields. What do you need to know about metal detectors?
How do metal detectors work?
As its name suggests, a metal detector is a device used to detect the presence of metal objects in an environment or on a person. Metal detectors are based on the phenomenon of electromagnetic induction.
To use a metal detector, simply switch it on and slowly explore the perimeter where you wish to detect a metal object. This is done by moving the device’s transmitter coil back and forth across the floor, facing you. When the device detects a metal object, it immediately emits an audible signal. Depending on the version of the detector, it can display data on the nature of the metal and the distance to it.
What are metal detectors used for?
Metal detectors were originally designed for professional use. However, as you can see from this article giving a detailed presentation of metal detectors https://www.weeza.fr/detecteur-de-metaux/, they can also be used for recreational purposes. Here, they are used to search for objects buried at a certain depth in the ground: gold, coins and other precious objects.
Returning to the professional uses of magnetic induction detectors, they are diverse. They are used in the field of security, to prevent users from entering with weapons and other dangerous metal objects in :
- airports
- governmental and international structures
- banks
- prisons and other establishments open to the public.
Metal detectors are also widely used in the military, notably by deminers and special forces. They can also be used by archaeologists. Metal detectors are also used in medicine to detect the presence of metal objects prior to MRI (Medical Resonance Imaging).
How to choose the right metal detector?
To ensure that your metal detector meets your expectations, you need to choose it carefully. There are several factors to consider.
Check the detector’s technology
As a general rule, you’ll find three main metal detector technologies on the market:
- beat frequency detection (BFO),
- very low frequency (VLF) detection,
- pulsed induction detection (PI).
Of these three technologies, pulsed induction is the most advanced. Depending on the type of metal detected, it offers good discrimination. What’s more, it boasts outstanding sensitivity, and precise ground balancing to avoid signal confusion. Unaffected by ground mineralization, pulsed induction detectors are ideal for environments such as beaches and desert areas.
As for detectors equipped with VLF technology, they represent a significant share of the magnetic induction detector market. This technology can be single-frequency, multi-frequency or simultaneous multi-frequency.
Which disks are used in metal detectors?
Discs are essential components in metal detectors. In fact, depending on the size of the disc, your detector can offer better performance. It increases the detection diameter and scans a larger surface area, while exploring deeper. However, if you replace the detection head associated with your original disc, you may lose performance: signal interference, loss of precision, etc.
For the best performance from your detector, opt for models with concentric heads, renowned for their precision and selectivity. Concentric heads focus the signal on the target for greater precision. In this case, the Spider disc is an interesting choice, as are the Widescan and DD discs. It all depends on the modalities (precision, depth, etc.) you prefer.
The shape of the discs also counts. Here, the best compromises are DD 20 X15 discs with elliptical heads. However, don’t overlook disc diameters, which can vary considerably between models and brands.
Opt for recognized detector brands
Brands are another important factor when choosing a metal detector. The market for metal detectors is fairly small. The best-known brands are : Minelab, Tesoro, Teknetics, Nokta Makro, Fisher, Detech, Garrett.
