Working Principle of Security Walk-through metal detector (WTMD)

Working Principle of Security Walk-through metal detector (WTMD)

WTMD works through the principle of electromagnetic induction, the internal transmitting coil generates a low-frequency alternating electromagnetic field, when the personnel carries the metal object through, the metal object will be induced to generate eddy currents and form a reverse electromagnetic field, which interferes with the original electromagnetic wave. The receiving coil detects this change in the electromagnetic field and converts it into an electrical signal, which is transmitted to the signal processing unit for analysis. Based on the comparison of the signal strength with the preset threshold, the system will trigger an alarm if the threshold is exceeded.

Modern WTMD usually adopt a multi-zone design, capable of detecting metal objects independently by means of coils in different zones. This design allows the WTMD to roughly determine the location of a metal object on the human body (e.g. head, torso or leg), thus improving inspection efficiency and accuracy. These zones are typically categorized as 3, 6, 12 or more zones. Improve detection accuracy and efficiency. In order to adapt to different scenarios, WTMD usually have a sensitivity adjustment function. By adjusting the sensitivity, the device can selectively ignore smaller metal objects (e.g. coins, keys) and only alarm detect larger, potentially threatening objects (e.g. knives, guns, etc.). The sensitivity adjustment can be set via the control panel. Once the WTMD an anomaly, the operator is usually alerted by an audible sound (buzzer) or visual signal (LED light). Some advanced devices can also indicate the approximate location or type of metal object.

The Walk-through metal detector EI-MD3000 D90 from our company adopts advanced electromagnetic induction technology and multi-zone detection design, with detection zones up to 90 zones, which can accurately identify different types of metal objects and accurately determine their location through the multi-zone positioning function. Ensure operators can respond quickly. Choose our intelligent WMTD to provide comprehensive and safe protection for your premises.