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Altai Technologies Ltd. All rights reserved
AX500 Series Installation Manual
12.
Surge Protection
12.1
Ethernet Cable Selection
Type of Ethernet cable in outdoor deployment is critical. The Ethernet cable should be either CAT 5e or CAT
6, outdoor rated, and shielded. Specifically, the following types of Ethernet cable should be used for
outdoor installation: screened fully shielded twisted pair (sFTP) cable, foiled twisted pair (FTP) cable, or
shielded twisted pair (STP) cable.
Unshielded twisted pair (UTP) Ethernet cable and/or unshielded RJ-45 jack are not recommended in
outdoor deployment due to increasing electromagnetic noise level. Furthermore, using shielded Ethernet
cable with unshielded RJ45 jack between the AP unit and PoE injector is not recommended. Improperly
grounded STP Ethernet cable acts as a magnet for static surges presented in the environment. Since the
charges discharged improperly, it couples with the data lines or power lines of the PoE cable. As a result, the
coupling high voltages which presents on the PoE cable may damage the AP. Therefore, it is very important
that using shielded outdoor rated Ethernet cable together with shielded RJ45 jack for outdoor deployment.
The differentiation between unshielded twisted pair (UTP) Ethernet cable and foiled twisted pair (FTP) cable
is that the latter has a small wire under the foil. This wire (preferably 2 cm longer than other wires), also
known as the drain wire, should be wrapped around the outside of the shield when installing the shielded
RJ45 plug. It is very important to have direct contact between the foil and the shield of the RJ45 connector.
Figure 12-1 shows a shielded, metal-enclosed RJ45 connector. First the boot is slid onto the cable, then the
cable shield and drain wire are folded back, next the load bar is loaded with the eight inner cable
conductors, then the load bar/cable assembly is inserted into the connector housing and crimped. Finally,
the boot is slid over the assembly for additional strain relief.
Figure 12-1 Shielded, Metal-enclosed RJ45 Connector
12.2
Ethernet Surge Protector Selection and Installation
It is
STRONGLY
recommended to install Ethernet surge protectors for outdoor AP deployment as it provides
additional and effective protection for the AP against electrical surge via Ethernet cable.
