Magnetic Locators VS Metal Detectors

Magnetic locators and metal detectors are similar devices. Both are used to find buried metal objects in the ground. However, metal detectors and magnetic locators work very differently from each other. This means that each device has its own strengths and weaknesses.

In this article, we provide an overview of what magnetic locators and metal detectors are, how each device works, and the ideal circumstances in which to use each device.

What is a Magnetic Locator?

Magnetic locators are handheld devices used to detect ferromagnetic materials buried underground. Ferromagnetic materials can be made of steel, stainless steel, iron, cast iron, or any other iron-based metal that is magnetic.

What is a Metal Detector?

Metal detectors are handheld devices used to locate buried metals of all types. Due to the way a metal detector functions, it can detect items that conduct electricity. This means that even non-metallic materials can be detected, such as graphite rods or some anthracite coals.

How a Magnetic Locator Works

To understand how a magnetic locator works, we must first cover a few basics of magnetism.

• Magnets and magnetized items each have a north and south pole. This includes every ferromagnetic item: from refrigerator magnets to the earth itself.
• Magnetic fields can be induced on non-magnetic items if they are ferromagnetic. An example of induction is when a strong magnet is put next to a steel paper clip. The paperclip can then magnetically attract a staple even though it is not normally magnetic. A magnetic field has been created or “induced” in the paperclip by the strong magnet.
• Magnetic poles and induction work at all scales, from the very small to the very large. This means that all ferromagnetic items will have a slight magnetic field that has been induced by the magnetic field of the Earth itself.

Now that we have covered some of the basics of magnetism, let us dive into how a magnetic locator works.

Magnetic locators are equipped with two sensors, one near the handle, and one near the tip. The sensor in the handle is used to read the magnetic field of the Earth. The sensor in the tip is used to read magnetic fields in the ground.

If a ferromagnetic item is buried nearby, it will have its own magnetic field induced on it by the Earth’s gravitational field. The difference between this magnetic field and the Earth’s magnetic field will be read by the two sensors and a signal will be sent to the operator.

How a Metal Detector Works

A metal detector works through electromagnetic induction. The head of a metal detector contains two coils. When a current is run through the first coil, an electromagnetic field is created on either side of the coil. As the head of the detector is swung, this moving electromagnetic field will induce a complementary electromagnetic field in any conductor within range.

The conductor in the first field then becomes electromagnetically charged itself. This secondary induced field is read by the second coil. The operator is then notified by the metal detector, usually with audio or visual signals.

When to Use a Magnetic Locator

Since magnetic locators can read small differences in very weak magnetic fields, they are extremely sensitive devices. They can locate ferromagnetic items at greater depths than a metal detector and can locate smaller items. In addition, a skilled operator can use the high sensitivity of a magnetic locator to identify the size, shape, and depth of an item before digging.

Magnetic locators are also less sensitive to electromagnetic interference generated by power lines and other external power sources than metal detectors. This is because they work solely with magnetic fields.

However, unlike metal detectors, magnetic locators can only locate magnetic items: those made from steel or iron. Other conductors such as copper, brass, gold, and lead, cannot be read by magnetic locators. This can be useful in areas with a lot of trash where only magnetic items are being searched for.

When to Use a Metal Detector

Metal detectors are best used for nonferrous items such as brass, gold, silver, copper, and aluminum. They will also detect iron items, but large iron signals can occasionally “null-out” or overload a metal detector.

Since metal detectors read the presence of materials by their conductivity, the signals can be sorted by how well a metal conducts electricity. This allows some metal detectors to have “discrimination” settings that enable the user to null-out signals from unwanted metal types.

Metal detectors are great at finding all metals, but they will be outmatched on iron or steel items when it comes to detection at depth.

Conclusion: Magnetic Locators vs Metal Detectors

Metal detectors and Magnetic Locators are both useful devices for locating metal objects. Each device has its own strengths and weaknesses which should be considered before beginning a locating project.

If you are looking for more information on magnetic locators, please feel free to review our Ultimate Guide to Magnetic Locators article. If you would like to view the magnetic locators that are for sold by Precision Outdoor Tech, then head over to our Magnetic Locators collection page.

If you are deciding on whether a metal detector or magnetic locator is best for your location needs, please feel free to contact us here. We will be glad to listen to your needs and to point you in the right direction for equipment appropriate to your project.