Walk-through metal detectors (WTMDs) are used at airports, transportation venues, government facilities, and other buildings to screen individuals for concealed weapons or other contraband. WTMDs typically consist of a rectangular archway, wide enough for one person to pass through, and visible and audible alarm indicators. They may be designed to be installed at a specific location or to be easily transportable to different locations.
Current Technologies of Walk-thru metal detectors(WTMDs):
WTMDs identify metal objects by sensing the metal’s interaction with a magnetic field. The magnetic field may come from the device (active detection devices) or from the ever-present magnetic field of the Earth (passive detection devices). In active detection, the magnetic field is generated by a transmitter coil in the device. Two categories of active detection technologies are distinguished by the types of magnetic fields that they transmit:
A. Pulse induction (PI) detectors transmit a pulsed or time-varying field that induces an electric current, or eddy current, in a target metal object passing through the portal.
Current generates an opposite magnetic field in the metal object. Electronic circuitry analyzes the pulse decay at the receiver and identifies the presence of a metal object by sensing the slight difference in decay time caused by this additional magnetic field.
B. Continuous wave (CW) detectors transmit a continuously oscillating magnetic field that also induces eddy currents and magnetic fields in metal objects passing through the portal. In these detectors, electronics analyze small changes in the phase and amplitude at the receiver to identify the presence of metal objects.
The principle of security metal detector gate:
First, It is sinusoidal oscillation of 3.5-4.95M by crystal oscillator. The frequency divider is divided into sine wave of about 7.8K. After power amplification by triode and coil, input into the large coil of door panel (6 zone) for electromagnetic wave emission. The coils in zones 1-6 are received separately. After receiving, the received signal is compared with the reference signal. After the change is found, the output level of the acquisition card is changed. The CPU scans the data of the six location acquisition cards within 300 milliseconds to determine the location of the metal and output the display.
Second, the structure : the door panel structure: consists of a large coil, 6 small coils, compensation coils and graphite. 2, the head host structure
Third, the detection time workflow CPU detection → a group of infrared blocked → detect whether the data of each acquisition card changes → alarm → detect another group of infrared → reset re-detection.
Key points of purchasing the stable and quality walk through metal detectors:
1. High level of security check function:
Metal detector doors are required to have high security requirements, including the following
Through the security check factor:
(1) The uniformity of the magnetic field is the key to the 100% detection rate;
(2) The security investigation and search force must be sufficient to detect any hazardous metal objects, regardless of their entry position and angle of view;
(3) The security investigation and search force must be sufficient to detect the passing of the personnel at any speed;
(4) It is necessary to have the ability to simultaneously detect iron and non-ferrous metals.
2. High level of visibility:
It is required to be able to distinguish small amounts of hazardous metal objects (such as small arms) from various metal materials carried by individuals.
The resolution is based on the following factors:
(1) Uniform consistency of magnetic field distribution;
(2) Various analytical capabilities of metal materials;
(3) Immunity to external motor noise interference;
(4) Immunity to external mechanical interference;
3. Excellent (noise interference):
Immune noise interference is an important factor affecting the performance of metal detectors. The noise interference is divided into the following types:
(1), instantaneous noise: the noise generated by the motor, the electronically controlled lock, and the co-load on the power line;
(2) Intermittent noise: radio frequency noise generated by the power supply device on the voltage;
(3) Noise generated by other nearby metal detectors;
(4) Noise generated by moving or vibrating metal mass.
4. Equipment proper rate:
To consider the proper rate of equipment, you can observe from two points:
(1) Whether to assemble an electronic substrate using SMD technology;
(2) Whether the control panel host performs functional test.
In addition to the above characteristics, the metal detector door with high efficiency has different requirements for the safety of use, the ease of operation, and the practicability of the product.
How to judge a stable and good quality walk through metal detectors?
1. High level of security check function:
For standardized testing, the NIJ 0602 standard is usually mentioned.
The NIJ 0601.02 Walk Through Metal Detector Test Kit is designed to maintain and improve the security of correctional facilities and enhances the security of security personnel. These kits are particularly effective for random testing of operator alertness and training of new detector operators .
Professional manufacturers are equipped with NIJ test tools to commission equipment to meet international safety levels.
If the supplier is unable to provide a professional NIJ test tool, you can also replace the test with a regular coin or other small metal object.
First test the uniformity of the magnetic field, and use the test kit to walk through the middle,left, right, upper or lower of the security metal detector door if the alarm area is correct. At the same time, the test kit is randomly hidden in any part of the body, and the device can accurately detect and alarm to indicate the correct position.
Iron and non-ferrous metal detection, preparation of relevant test bodies, including iron, copper, aluminum, gold, silver, etc., carrying such objects pass through the archway metal detector, whether it can correctly alarm and indicate the corresponding location.
2. Highly discrimination of security metal detectors:
Walk through metal detector doors to maximum ignore the safety metal objects carried by individuals, such as buttons, belts, zippers, mobile phones, and leather shoes. And alarms for dangerous metal objects, such as pistols,guns, knives, bombs, etc.
3. Excellent anti-interference and environmental adaptation:
The metal detector system can have more than 100 frequency adjustable, avoiding multiple devices running in the same place and causing false alarms. When the surrounding environment of the device changes or is closing to a large metal, the security metal detector gate can adjust itself and the system automatically adapts. The alarm can be prepared during operation without being disturbed by the surrounding environment or large metal objects.
4. Equipment suitability check:
The modular design and assembly are simple and convenient, and the main control box is sealed, dustproof and waterproof. Adopt a one-piece main control board, maintenance free. Whether the system has functions can automatically diagnose and report errors. Whether the system can arrange visual sensitivity adjustment: for example, it is necessary to ignore specific metal objects, and the system can enter the learning mode by visualizing sensitivity adjustment, and the test can not alarm for specific metal objects.
Which is the best brand of walkthrough metal detectors?
The following six brands recommended for the development and production of walk through metal detector doors, all of them have unique features, so that their brand image in the international market is highly praised and recognized.
Please see the picture below:
(Note: The following description of the ranking does not represent the world ranking of each brand.)
1. CEIA from Italy.
In recent years, ceia's international market share has been increasing. In particular, the 60-zone detection security metal detector door with core technology is in the lead of the world.
2.Fisher from USA
Fisher is a manufacturer of established metal detectors. In the field of security screening and detection, it is widely known that the portable folding security door has the characteristics of long battery life and easy movement.
3. Garrett from USA
Garret is also an established manufacturer specializing in metal detection. In the security scanning market, the most popular is the 33 zones security metal detector gate with model NO.:PD6500i.
4. RSD(Ranger)from USA
As a security scanning system supplier, RSD has the most stable and durable features for walk through metal detectors. But it seems that the influence of the international market is decreasing recently.
5. Rapiscan from USA
As a professional security scanning and detection integration solution provider. In recent years, it has been involved in the production and development of security metal detector gates.
6. Autoclear from USA
Also as a professional manufacturer of security scanning and detection systems, how can there be no security metal detector door products?Security inspection x-ray machines and metal detector doors have become a standard requirement for each project.
7. Securina from China , waiting for your testing and comments :) :) :)
Securina focuses on R&D security metal detectors with a 15years experiences engineer team. It's the first company to develop and sell a single control panel system(One-piece control board) with stable operation and zero failure rate within two years in China.
Each brand Walk-through metal detectors recommend system details and prices:
1. CEIA: PMD2 Plus Walk-through metal detector:
Technology: Continuous Wave Detector (CWD)
Assembly (minutes): 7 minutes
Detection zone: 60 zones
Detection program: 40 standard programs
Sensitive levels: 0-200 selectable sensitivity range settings
Random alarm: 0-100% available
Remote program：available (options)
Remote monitoring: available (options)
Basic physical details of PMD2 Plus:
Overall Dimensions: 2255 (H) x 1065 (W) x 600 (D)mm;
Passageway Clearance: 720(W) x 2050(H) mm
Net Weight: 56 kgs
Operating temperature range: -20ºC to 70 ºC
Relative humidity range: 0 to 95%, non-condensing
Weatherization: IP65 option: available
Power: 100-240 volts alternating current (VAC)
Battery: optional battery backup
Warranty: 2-year parts and in-house labor
Price range: USD3,500.0-USD5,999.0
2. Fisher M-Scope Walk Through Metal Detector:
Technology: Pulse Induction Detector (PID)
Assembly (minutes): 5 minutes
Detection zone: 3 zones
Detection program: 4 standard programs
Sensitive levels: 0-100 selectable sensitivity range settings
Random alarm: Non-available
Remote program：Non-available
Remote monitoring: Non-available
Basic physical details of Fisher M-scope:
Portable Dimensions: 940 (L) x 610 (W) x 660 (H)mm;
Weight: 38 kgs
Operating temperature range: -20ºC to 70 ºC
Relative humidity range: 0 to 95%, non-condensing
Weatherization: IP65 option: available
Power: 100-220 VAC; runs on two internal 12-volt batteries that recharge when unit is plugged into AC power.
Battery: 40 hours battery life
Warranty: 2-year parts and labor
Price range: USD4,000.0-USD5,000.0
3. Garrett PD 6500i Walk Through Metal Detector :
Technology: Pulse Induction Detector (PID)
Assembly (minutes): 15 minutes
Detection zone: 33 zones
Detection program: 20 application programs
Sensitive levels: 0-200 selectable sensitivity range settings
Random alarm: 0-50%cavailable
Remote program：available (optional)
Remote monitoring: available (optional)
Basic physical details of Garrett PD6500i:
Portable Dimensions: 2210 (H) x 900 (W) x 580 (D)mm;
Passageway Clearance: 760(W) x 2030(H) mm
Net Weight: 74 kgs
Operating temperature range: -20ºC to 65 ºC
Relative humidity range: 0 to 95%, non-condensing
Weatherization: IP65
Power: 100-220 VAC; 50 or 60 Hertz, 45Watts
Battery: 10 hours or 30 hours backup available(optional)
Warranty: 2-year parts and labor
Price range: USD4,000.0-USD5,999.0
4. RSD : Intelli-scan 33 Zone Walkthrough Metal Detector:
Technology: Continuous Wave Detector (CWD)
Assembly (minutes): 10 minutes
Detection zone: 33 zones
Detection program: 20 application programs
Sensitive levels: Non-available
Random alarm: Non-available
Remote program：Non-available
Remote monitoring: available (optional)
Basic physical details of Intelli-scan 33 zones:
Portable Dimensions: 2222 (H) x 900 (W) x 550 (D)mm;
Passageway Clearance: 760(W) x 2040(H) mm
Net Weight: 81 kgs
Operating temperature range: -20ºC to 65 ºC
Relative humidity range: 0 to 95%, non-condensing
Weatherization: optional for outdoor using
Power: 115-230 VAC; 50 or 60 Hertz
Battery: available(optional)
Warranty: 2-year parts and labor
Price range: USD2,999.0-USD4,999.0
5. Rapiscan Metro 6S Walk-thru Metal Detector:
Technology: Continuous Wave Detector (CWD)
Assembly (minutes): 10 minutes
Detection zone: 20 zones
Detection program: 10 application programs
Sensitive levels: 0-100 selectable sensitivity range settings
Random alarm: available
Remote program: available(optional)
Remote monitoring: available (optional)
Basic physical details of Rapiscan Metro 6S:
Portable Dimensions: 2240 (H) x 850 (W) x 700 (D)mm;
Passageway Clearance: 710(W) x 2050(H) mm
Net Weight: 63 kgs
Operating temperature range: -20ºC to 60 ºC
Relative humidity range: 0 to 95%, non-condensing
Weatherization: IP 55
Power: 115-230 VAC; 50 or 60 Hertz
Battery: 8 hours available(optional)
Warranty: 2-year parts and labor
Price range: USD2,999.0-USD4,999.0
6. AutoClear, LLC: CheckGate® 8000 Walkthrough Metal Detector:
Technology: Pulse Induction Detector (PID)
Assembly (minutes): 10 minutes
Detection zone: Single zone
Detection program: 70 standard programs
Sensitive levels: 0-100 selectable sensitivity range settings
Random alarm: Not available
Remote program：Not available
Remote monitoring: Yes, in options
Basic physical details of Autoclear CheckGate 8000:
Overall Dimensions: 2200 (H) x 890 (W) x 610 (D)mm;
Passageway Clearance: 711(W) x 2022(H) mm
Net Weight: 48 kgs
Operating temperature range: -10ºC to 55 ºC
Relative humidity range: 0 to 98%, non-condensing
Weatherization option: available
Power: 90-265 volts alternating current (VAC)
Battery: optional battery backup
Warranty: 1-year parts and labor; extended warranty available
Price range: USD2,000.0-USD3,999.0
7. Securina SA300S Walk Through Metal Detector :
Technology: Continuous Wave Detector (CWD)
Assembly (minutes): 10 minutes
Detection zone: 33 zones (45 zones in optional)
Detection program: 60 application programs
Sensitive levels: 0-300 selectable sensitivity range settings
Random alarm: 0-20% available
Remote program: available(optional)
Remote monitoring: available (optional)
Basic physical details of Securina SA300S:
Portable Dimensions: 2210 (H) x 880 (W) x 600 (D)mm;
Passageway Clearance: 760(W) x 2010(H) mm
Net Weight: 80 kgs
Operating temperature range: -20ºC to 55 ºC
Relative humidity range: 20 to 95%, non-condensing
Weatherization: IP 65
Power: 100-240 VAC; 50 or 60 Hertz, 15Watt
Battery: 4 \ 8 \ 10 \ 12 hours available(optional)
Warranty: 2-year parts and labor
Price range: USD999.0-USD1,999.0
(If any information is wrong, please feel free to correct us. Thank you.)