User's Manual

SIDEP
Page 10 of 19
therefore, a dedicated line shall be provided directly from the switching board.
This line shall be installed by an approved installer.
A number of switching power supplies as used e.g., in Electronic Information
Systems (EIS) operate at a harmonic frequency similar to that of the EAS
SYSTEM and may cause system jamming and therefore, under no
circumstances should the power supply unit be connected to a line backed up
by an Uninterrupted Power Supply (UPS) (rectified current).
Metallic masses generate interference because of system absorbed and
reverberated electromagnetic waves.
Avoid installing antennas close to such metallic masses while keeping to a
minimum distance of 60 cm.
In case of implementing problems because of the site configuration, perform
testing in order to determine the best location.
Metal frames or guide bars sometimes behave like resonance circuits tuned to
the system frequency. Install antennas remotely from these structures or fit
bonding braids in order to cancel resonance phenomena.
Steel frames of doors sometimes behave in the same manner. Install antennas
remotely from such structures or fit shunts or bonding braids in order to cancel
resonance phenomena.
Position the system away from steel frame door(s), then open and close door(s)
and check the LED level bar for evidence of distorted signals (tag signal).
Defective fluorescent lighting, e.g. neon type, generates interference because
of permanent DC energizing on switching on. Please feel free to have this type
of lighting switched off and compare results with the LED level bar. Some
transformers used in this type of lighting appliances may be defective and
cause similar interference.
All electromagnetic field generating appliances typically incorporate
transformers, motors or mobile magnets, including: fluorescent neon tubes,
halogen quartz bulbs, cashiers conveyor belts, etc.
Power leads may also be a cause for interference. Prevent antennas from
standing too close to electrical leads. Move antennas and perform various
tests to assess the best location.