EM LIBRARIES System
Electromagnetic (EM) Systems
These tags are made of a strip of amorphous metal (metglas) which has a very low magnetic saturation value. Except for permanent tags, this strip is also lined with a strip of ferromagnetic material with a moderate coercive field ( magnetic “hardness” ). Detection is achieved by sensing harmonics and sum or difference signals generated by the non-linear magnetic response of the material under a mixture of low-frequency ( in the 10 Hz to 1000 Hz range) magnetic fields.
When the ferromagnetic material is magnetized, it biases the amorphous metal strip into saturation, where it no longer produces harmonics. Deactivation of these tags is therefore done with magnetization. Activation requires demagnetization.
The Advantages of EM:
- Ability to secure metal articles
- Widest range of adhesive security labels
- Smallest type of labels available
- Capacity to reactivate labels makes them ideal for libraries and video rental service.
- Ability to detect tags tight-shielded by aluminium foil
The EM Technology is used by many:
- Libraries
- Bookstores
- Cosmetic stores
Antenna Specification
- EM-4000: 1500 x 590 x 100mm
- EM-5000: 1450 x 545 x 120mm
- Controller: 61 x 340 x 20mm