Table Of Contents
Cisco 4G Lightning Arrestor (4G-ACC-OUT-LA)
This document describes the Cisco 4G Lightning Arrestor kit for use on Cisco 4G wireless devices, and provides instructions for mounting the arrestor.
The Cisco 4G-ACC-OUT-LA provides a level of safety protection to the user as well as to wireless equipment by shunting to ground over-voltage transients induced into outdoor antennas and cables. These transients, in mild cases can produce interfering signals in a wireless system, and in extreme cases, can be dangerous and destructive.
Overvoltage transients can be created through lightning static discharges, switch processes, direct contact with power lines, or through earth currents. The Cisco 4G-ACC-OUT-LA Lightning Arrestor limits the amplitude and duration of disturbing interference voltages and improves the overvoltage resistance of in-line equipment, systems, and components. A lightning arrestor installed according to these mounting instructions balances the voltage potential, thus providing safety and preventing inductive interference to parallel signal lines within the protected system.
The Cisco 4G-ACC-OUT-LA Lightning Arrestor is designed for use with Cisco 4G wireless devices, and antennas and cables that use standard TNC connectors.
Warning Do not work on the system or connect or disconnect cables during periods of lightning activity. Statement 1001
Warning Only trained and qualified personnel should be allowed to install, replace, or service this equipment. Statement 1030
Warning To report a gas leak, do not use a telephone in the vicinity of the leak. Statement 1039
Warning Disconnect or switch off in-line equipment when installing or inspecting lightning arrestors during an electrical storm.
Warning When connecting lightning arrestors, make sure that the succeeding equipment and components are disconnected or turned off.
Warning Do not work on the system or connect or disconnect cables during periods of lightning activity.
Cisco recommends that you bulkhead mount the lightning arrestor so it can be installed as a wall feed, going through the wall of the protected space.
The importance of obtaining a good ground and bonding connection cannot be overstressed. Consider these points when grounding the lightning arrestor:
•Connect the lightning arrestor components directly to the grounding point.
•Ensure the contact points of the ground connection are clean and free of dust and moisture.
•Tighten threaded contacts to the torque specified by the manufacturer.
Installing the Lightning Arrestor
This lightning arrestor is designed to be installed in series between the antenna cable that is attached to the 4G outdoor antenna and the second antenna cable entering the building. Cisco recommends that the arrestor and its ground connection is made as close as possible to where it enters the building, either just outside or just inside the building.
Cisco recommends that the lightning arrestor be bulkhead-mounted and grounded (i.e., arrestor attached directly onto a well-grounded bracket or well-grounded panel via the arrestor's threaded shaft and the supplied nut). If this is not possible, then the next best option is to use the ground lug provided with the kit. The ground lug requires a 6 AWG copper ground wire (user provided) to be crimped onto the lug, with the other end of the ground wire connected to a good solid ground point (e.g., to an electrical ground buss bar), keeping the ground wire length as short as possible for best results (under 20 inches [0.5 meters]). See Figure 1.
Figure 1 Lightning Arrestor (4G-ACC-OUT-LA) Details
Protected side TNC Plug (to 4G device)
Unprotected side TNC Jack (to antenna)
Note This lightning arrestor is part of a lightning arrestor kit. The kit contains a lightning arrestor, a grounding lug, and this instruction sheet.
Note When you install the lightning arrestor, follow the regulations or best practices applicable to lightning protection installation in your local area.
Coaxial cable loses efficiency as the frequency increases, resulting in signal loss. The cable should be kept as short as possible because cable length also determines the amount of signal loss (the longer the run, the greater the loss).
Cisco recommends a high-quality, low-loss cable for use with the lightning arrestor.
Obtaining Documentation and Submitting a Service Request
For information on obtaining documentation, submitting a service request, and gathering additional information, see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation, at:
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