Metal detectors create a magnetic field around their search disk, and when a metal object is placed within the range of the magnetic field, the intensity of the magnetic field changes, and with these changes, the metal detector notices the presence of metal around its disk. And it becomes clear and aware
Types of metal detectors and their use
There are different types of metal detectors and each one works in a different way according to its specific application.
These devices are generally divided into the following seven categories:
- Recreational Metal Detectors (VLF)
- Pulsed or advanced (PI) metal detectors
- Industrial metal detectors
- Metal detectors with the possibility of transmitter and receiver (TR)
- Frequency metal detectors
- Magnetic metal detectors
- Video metal detectors
We will explain each of them below.
Recreational Metal Detectors (VLF)
Recreational metal detectors known as very low frequency metal detectors are very light and have small discs (about 25 cm).
These types of metal detectors have a lower penetration depth than other metal detectors, and their metal exploration depth is usually between one and two meters. VLF devices are designed to find metal objects that are very close to the surface of the earth and have an advanced digital display screen.
Recreational metal detectors have a resolution of approximately 80%, in other words, these metal detectors can separate ferrous metals from non-ferrous metals with 80% accuracy.
Pulse or advanced metal detectors (PI)
This metal detector has much more power than other metal detectors, pulse metal detectors with a loop of 45 cm have the ability to identify metals in a large volume up to 2 meters and detect small metals at a depth of 40 cm.
Advanced metal detectors (pulse induction) have a relatively heavy weight because they use heavy batteries in their construction, and usually the metal detector itself or their battery is attached to the belt and does not have a monitor, and they are simple.
Advanced metal detectors (PI) do not have a high resolution and cannot separate ferrous metals from non-ferrous metals and will report seeing any metal or alloy.
The advanced type of these devices with the PI-BH working system, which are modified pulses and have more power in separation and depth, are also available.
Industrial metal detectors
Industrial metal detectors are used in various industries such as machine carpets, packaging and lumber industries, and factories.
Metal detectors with the possibility of transmitter and receiver (TR)
Transmitter and receiver metal detectors consist of a transmitter disk in front and a receiver disk at the end of the device, which are usually square in shape.
Transmitter and receiver metal detectors do not have separation power and are only designed to find large metals such as water pipes and large metal veins, and are sometimes called mass detectors.
Working with these metal detectors is difficult and due to the difficulty of setting the metal detector, losing the target, many mistakes and mistakes in determining the exact location of the metal, it has not been widely sold.
Frequency metal detectors
These models of devices are induction frequency or absorption metal detectors with EDIT or VDI DISC separation and detection settings and threshold or target X level and volume, most of the gold detectors are of this type.
The use of frequency metal detectors requires experience and practice, so that the application can adjust the low frequency metal detector according to the situation and identify the main target in any type of work scene.
Magnetic metal detectors
The function of this category of metal detectors includes detecting the phase difference caused by the changes related to the magnetic field conditions in the seeker head or coil, loop and magnetic sensor.
Any type of magnetic change from minerals, sources or changes in the earth’s layers in the work scene can cause a reaction or response in these devices, such as the target metal or gold, and the metal detection settings in the magnetic metal detector are all metals and separation.
Video metal detectors
Image metal detector is called metal detection, which, in addition to the ability to identify metal, has the ability to scan and present the image of the desired metal in an estimated and bounded manner, which generally can be trusted 60% of the image.
This model of metal detectors work based on the magnetic field and can identify holes and old metals that have been buried in the soil for years based on color. All video metal detectors have a magnetometer sensor and are not sensitive to modern metals, and the scanning of these metal detectors is usually done by the famous Visua Laser software.
