Fiber optic cabling with PoE converters
allows long-distance IP camera placement
Power
over Ethernet (PoE) technology enables powering IP surveillance cameras through
the transfer of DC electrical power along with data over standard unshielded
twisted pair (UTP) cabling. This cabling connects to a network device through
an RJ-45 port that injects the power from power sourcing equipment such as a
PoE switch or midspan PoE injector. PoE provides a flexible and convenient
means of powering devices that are located in out-of-the-way locations, and
saves money by eliminating the expense and difficulty of direct electrical
wiring. A challenge with PoE is reaching remote locations outside the distance
limitation of UTP cabling. According to the TIA/EIA 568-5-A standard for
category 5e cable, the maximum length for a cable segment is 100 meters (328
ft), and PoE power injectors or midspans do not increase the distance of the
data link.
So, how
do you get beyond that 100-meter limit? Once answer is through fiber optics.
Fiber optic cabling is an effective method to overcome the distance and bandwidth
limitations of UTP, and media converters are a commonly used to integrate
copper network equipment and fiber. Since DC power cannot be conducted over
fiber, PoE media converters are the solution to extend network distances via
fiber to remote IP cameras. A PoE media converter converts the fiber to copper,
and sends DC power to the camera over the UTP cabling.
How PoE Media Converters Work
On the main article image/PoE schematic that appears at right, an Ethernet
switch with RJ-45 ports resides in a control room or data closet. The copper
UTP cabling is converted to fiber with a standard media converter. The fiber is
run a long distance to the PoE media converter located near a convenient AC or
DC power source, where it converts the fiber back to copper UTP. The PoE media
converter also functions as a power-sourcing mini switch, and injects PoE (DC
power) over the UTP cable. At the other end of the UTP cable is the IP camera,
located up to 100 meters away from the PoE media converter.
PoE media converters are available with Gigabit Ethernet
and Fast Ethernet data rates and can support PoE (15.4 watts) or PoE+ (25.5
watts). PoE media converters function like PoE mini-switches, and are available
in a variety of multi-port configurations, including dual RJ-45 and dual fiber
ports. They can support fixed fiber connectors or small form pluggable
transceivers.
To understand those power specifications, it’s worth
knowing that in 2003, the IEEE ratified the 802.3af PoE Standard. That standard
provides up to 15.4 watts of power per port. Late in 2009, the IEEE ratified
the 802.3at PoE Standard known as PoE+ that provides up to 25.5 watts of power
for each port. PoE+ can be required to power IP cameras with Pan-Tilt-Zoom
(PTZ) capabilities, and weather-hardened cameras used in cold
environments.
Key Features to Consider When Selecting a PoE Media Converter:
• PoE+ to future proof applications
• Out-of-the-box support for IEEE Alternative A and B,
and Legacy Power detection
options (without the need for jumper wires or external
cables)
• Jumbo Ethernet Frames to enhance throughput for
reliable data flow
• Multiple port configurations for deploying a variety of
architectures and topologies:
– Daisy chain media converters or
install in ring topology
– Redundant fiber with less than 50ms
switch over time
– Dual UTP ports for powering two PoE
devices per converter
• Ability to be powered by either AC or DC power source
• Industrial hardened temperature ranges for outdoor
applications
• Determines and delivers the specific power level
required by the PD
• Fully configurable DIP-switches for easy set up:
– Link Fault Propagation Modes
– PoE Power Reset on fiber Rx loss
that automatically resets
Leverage the Benefits of Fiber
There are several solutions available to extend the distances of PoE
network links, including LAN extenders that convert Ethernet to DSL, UTP to
coax converters and wireless technology. When you’re going long distance,
however, fiber optic cabling provides several advantages over these
technologies.
Unlike copper, fiber extends network distances up to 87
miles (140 kilometers) per link with no data deterioration over distance
(signal deterioration is to be expected in copper cabling). LAN extenders can
only extend network distances about 3,300 feet, but a data rate of 100 Mbps can
drop by 70 percent at longer distances.
Fiber cabling provides security benefits as well. It is a
secure medium that generates no electro-magnetic emission and is very difficult
to tap. Fiber is also very reliable because it is not susceptible to electrical
interference, or data loss due to temperature or atmospheric conditions.
【Installation Steps】
1) Please turn off the signal source and the device's power, installation with power on may damage the device;
2) Check if the network cable and other transmission line that will be used is occupied by other device;
3) Use a network cable to connect video to POE Ethernet Optical Transceiver's LAN port with PoE IP camera or other PoE network device;
4) Use two single mode double optical fibers to connect two converter's optical port, please attention the optical fiber which connect the RX and TX port should be across; that means one optical fiber, one side is to connect the optical module TX port, the other side should connect the RX port;
5) Check if the installation is correct and device is good, make sure all the connection is reliable and power up the system;
6) Make sure the Ethernet and PoE power supply is working normal.
Another Application:
