Using A Dc Power Source - Cisco AIR-LAP1310G Mounting Instructions

Using a DC Power Source

The access point can be powered from a DC power source using the optional LR2T power injector. The
following sections identify the maximum cable length that can be supported in these environments using
a few different coax cable types.
When choosing cables other than those shown in the following examples, take care to ensure that the RF
characteristics of the new cable meets or exceeds the RF characteristics of the cable examples up to
500 MHz. Also, be sure to use good quality cable connectors and grounding blocks such that the DC
resistive losses associated with all the connections "combined" are less than 0.2 ohms.
Warning Only trained and qualified personnel should be allowed to install, replace, or service this equipment.
Statement 1030
The Cisco Aironet Power Injector LR2T must be used with a DC power source.
Note
Electrical Load-Dump Protection
In battery power systems, a load-dump occurs when the battery is disconnected from the charging system
while supplying power, and the devices connected to the battery system must dissipate the very large
energy transient that is produced. For example, this situation can occur if the battery cables are loose or
in a service shop where a mechanic accidentally removes the battery cable while the engine is running.
In order to comply with the transportation vehicle load-dump requirements specified in SAE 1211 and
SAE1455 standards, you must use an external load-dump protection device. This device must be
connected to the power cable between your vehicle's battery system and the power injector.
You must install an external load-dump protection device in all vehicle systems that can experience a
load-dump and that are supplying +24 VDC (or above) to the power injector.
For more information on load-dump protection devices, refer to Appendix I of the Cisco Aironet 1300
Series Outdoor Access Point/Bridge Hardware Installation Guide.
DC Power Cable and Connector
When using a DC power source, you are responsible for providing the power cable, fuse, and power
connector used for the power injector. The power injector requires an external power supply capable of
supplying 13 W of power at a typical vehicle battery voltage: +12 VDC, +24 VDC, or +40 VDC. For the
power cable, the positive voltage is connected to the center pin and the return is connected to the external
barrel of the power plug.
Warning A readily accessible two-poled disconnect device must be incorporated in the fixed wiring.
Statement 1022
Connect the unit only to DC power source that complies with the safety extra-low voltage (SELV)
Warning
requirements in IEC 60950 based safety standards. Statement 1033
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Cisco Aironet 1300 Series Lightweight Outdoor Access Point Mounting Instructions
Using a DC Power Source
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