Counteracting Magnetic Fields
People often take the wonders of magnetic fields for granted, but they can also be strong enough to adversely affect our electronic equipment if not properly managed. Magnetic fields are invisible forces that exist everywhere in nature. The Earth’s magnetic field helps to protect us from cosmic radiation and can also be used for navigation and mapping. Humanmade magnets can be used for a variety of purposes, most notably in the production of electricity in the form of alternating current. However, when magnetic fields are too strong or are even conflicting, it can create a problem.
The magnetic fields around our electronics and in other instruments have to be properly managed or “counteracted” in order to protect them from any potential damage or interference. Magnetic fields that are too strong can scramble the delicate circuits of our computer, television, or other devices, resulting in noticeable interference or permanent damage. The physical components of our electronic devices, such as wires and chips, are also vulnerable to interference and can be affected by too much magnetic flux.
The trick to counteracting the physical effects of a magnetic field is to set up an opposing magnetic field. This is done by using a device called a “magnetic shield” or “magnetic deflector”. Basically, this is a device that generates a magnetic field in the opposite direction of the interfering field. The strength and shape of the magnetic shield can be adjusted based on the exact type of interference that needs to be dampened or kept out.
The most basic and common types of magnetic shields are constructed from soft ferromagnetic materials like iron and steel, which will act as a barrier to the magnetic field and block or reduce its effects. These materials can be folded into concentric circles or wound into specific shapes to better capture and absorb the unwanted field.
The next level of protection from magnetic fields comes in the form of active shielding. This method uses an active component like a coil or electromagnet in conjunction with the basic ferromagnetic shield to provide extra protection and dampening. The active component generates its own magnetic field, and when this magnetic field is aligned properly with the offending field, it can actually cancel out or reduce the overall magnetic field strength. This type of active shielding is often used to protect sensitive equipment like medical imaging devices and high-speed communication systems.
Finally, there are several passive countermeasures that can be employed to reduce the effects of magnetic fields. Routing cables away from areas taking high magnetic flux readings is one, as well as placing small ferromagnetic materials like steel boxes into the right areas. Other passive methods include surface treatment and specialized fabrics designed to absorb, re-direct, or dampen the unwanted field.
Overall, magnetic fields are everywhere, but they don’t have to be a nuisance. Through shielding, routing, and other countermeasures, we can keep magnetic flux from impairing our electronics and other delicate instruments, allowing us to use them without fear of interference.
