Getting Started
802.3at Powered Device (PD) Specification:
• 42.5 to 57 V DC at the PD, with 25.5 W maximum input power to the PD
802.3at Cable Specification:
• 100 m maximum length
• Maximum cable pair resistance of 12.5 Ohms, satisfied by using CAT5
or CAT5e as specified by ANSI/TIA/EIA-568 or Class D as specified by
ISO/IEC 11801:1995
• 600 mA maximum current per pair
1.4 Functional Earth Ground and Lightning Protection
Units are not designed to survive a direct lightning hit. However, they are
intended to withstand the voltage and current surges induced from nearby
lightning activity.
The level of required lightning protection depends on regional lightning
conditions and location of installation. For example, an AP installed on a roof
top requires greater lightning protection than an AP installed on the side of a
building. The following is a list of recommended installation practices to mitigate
the voltage and current surges induced from lightning activity. If there is a
conflict between these recommendations and local or national electrical codes,
the local or national electrical codes must be followed.
• For streetlight or hydro/telecom pole mounting the AC power adapter
should be protected with a lightning surge protector. AC power routed to
the power adapter must be routed inside the pole. If power is routed on the
pole exterior, the power must be routed through a metal conduit grounded
at the base of the pole.
• For rooftop installations, the unit must not be mounted at the highest point
on the building. If the building has installed lightning arrestors, the unit must
be located within the umbrella protection zone—a 60 degree zone under
the lighting arrestor, but if possible, the unit should not be located closer
than 30 feet (approx. 10 m) from the lightning arrestor. Power and Ethernet
cables must be routed through independent grounded metal conduits.
• For lightning surge protection, the installer must connect a separate ground
wire between the external chassis of the unit and a ground on the pole. The
ground point on the AP accepts a
1
/4” screw.
• It is recommended for areas susceptible to lightning activity, such as on
poles, rooftops, or on or near any tall structures, that shielded CAT 5e or
CAT 6 Ethernet cable be employed.
• The external antennas ports of the unit require lightning arrestors to be
employed whenever the external antenna is located more than 3 feet
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1/006 92-LZA 101 803 Uen D | 2013-12-13