User's Manual

Radio Activity S.r.l. 9 / 44
2.2 Improper use
It is recommended to install the equipment in closed cabinet, to allow only authorized people to access to
them, in order to avoid handling or improper use of equipment and to avoid accidental contact with hot
surfaces.
2.3 Power supply
The equipment requires a 13.2Vdc/5A, negative grounded, power supply. It is recommended to insert a 10A
fuse in the power supply cable near the power supply source (e.g.: a battery) to avoid dangerous damage
due to lightening event or to accidental short circuits along power supply cables.
The equipment is designed to be powered by a safe supply source which grants a double insulation of output
voltage from dangerous voltages. The electric plant must contain a switch to cut off power supply lines,
according to national law and directives.
Use only certified power supply devices and connect a ground cable to the GND Ø5MA nut to avoid lightning
and rescue problems. Remember that a lightning on the antenna system could pass the RF discharger arriving
to the chassis of the equipment. A robust GND cable short the energy preserving the other equipments in
the same site.
2.4 Antenna system / lightning
Providing adequate lightning protection is critical to a safe reliable communications site. Unless KAIROS has
got many protections, RF transmission cables, and AC and DC power lines must all be protected to prevent
excessive lightning energy from entering the site.
To reduce lightning problems, use lightning rod on the top of the radiating tower; anchor strongly the metallic
parts of the tower to the GND plane.
Insert, in coaxial cables coming from the antennas, adequate RF dischargers before to enter in the shelter
and connect them shortly to the extern GND plane.