Routing The Cables; Lightening Protection - Cisco AIR-BR1410A-A-K9 - Aironet 1410 Wireless Bridge Deployment Manual

An optional Roof/Wall mount kit is available - Cisco Part number AIR-ACCRWM1400

6.4 Routing the cables

The shielded Dual RG-6 cables connect to the 1400 Series outdoor unit to the grounding block
and then finally to the Power Injector. The Bridge comes with dual 50 and 20 Ft RG-6 cables.
Typically the 20 Ft cable is used from the grounding block to the inside of the building where
the Power injector is located. Additional cable can be purchased in 100 Ft lengths. Common
75 Ohm cable TV cable like the kind found in home appliance or electronic stores like Radio
Shack can be used if Cisco cable is not readily available.
Tip: Coaxial Cable length is limited to 100 Meter from power injector to the Bridge
When routing the cable down a radio tower one must secure the cable to the tower. This is
typically done by using plastic or nylon ties securing the cable to either one leg of the tower or
to the existing cables traveling down the tower. When using plastic or nylon ties one should
make sure the cable ties are UV (ultraviolet light) resistive so they will not crack or break from
exposure over time to the suns rays.
Always keep the coaxial cable away from sharp objects, if mounting on a roof top do not
stretch the cable across places where people will walk or move heavy equipment that might cut
or damage the cable. Always make sure the cable lies flat on the roof and never suspend it
where someone could trip over it.
Before the cable enters into the building make sure the cable is routed through the grounding
block and that care is taken to not damage or compromise the cable when routing it into the
building. Beware of sharp edges around the wire path or hole you are using to get the cables
into the building.
Tip: It is good practice to create a small cable loop around all outside connections.
Should the weatherproofing fail, this would limit the water damage to the loop
preserving the rest of the cable so that it could be spliced and reused.
Maximum cable length up to 200 meters is possible (100 meters of coax cable between Bridge
and power injector and another 100 meters of Category 5 cable between power injector and
Ethernet port).
6.5

Lightening Protection

Lightning is caused by the build up of electrical potential between the clouds and ground,
between clouds, or between clouds and the surrounding air. During thunderstorms, static
electricity builds up within the clouds. A positive charge builds in the upper part of the cloud,
while a large negative charge builds in the lower portion. When the difference between the
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