Frequent false alarms in EAS AM detection systems are typically caused by the following factors, which can be analyzed from four aspects: environment, equipment, labels, and operation:
1. Environmental Factors
Metal Interference: Metal objects such as door frames, shelves, brackets, and decorative parts near the detection door can interfere with the magnetic field, leading to false alarms.
Electromagnetic Interference (EMI): The presence of strong electromagnetic sources nearby (inverters, wireless equipment, mobile phone base stations, etc.) can interfere with AM signals.
Improper Door Installation: Doors near areas with high magnetic interference or improperly installed can cause the system to misjudge.
2. Equipment Factors
Aging or Damaged Antenna: Damaged antennas, aging wiring, or poor contact can produce abnormal signals.
Excessively High Sensitivity Setting: Excessively high sensitivity can trigger alarms even with weak signals.
Controller or Signal Processing Failure: Internal system malfunctions can lead to frequent false alarms.
3. Label Factors
Residual or Damaged Labels: Unremoved labels, damaged labels, or labels hidden inside packaging can trigger alarms.
Mismatched Label Types: Labels that are not AM or have different frequencies may cause interference.
Tag overlap or attachment to metal: This strengthens the signal and causes false alarms.
4. Operational and Management Factors
Incorrect tag removal: Improper operation by sales personnel may result in tags not being demagnetized or removed.
Goods placed too densely or near doorways: Increases magnetic field interference, leading to false alarms.
Insufficient system maintenance: Failure to clean dust around the antenna or regular calibration increases the false alarm rate.
Summary: False alarms in the EAS AM detection system are mainly caused by four categories of reasons: environmental interference, equipment status, tag problems, and improper operation.