Comnet CWGE2FE8MSPOE, Installation And Operation Manual

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Introduction
Power-over-Ethernet (PoE) eliminates the need to run VAC power to other devices on a
wired LAN. Using a Power-over-Ethernet system installers needs to run only a single
Category 5 Ethernet cable that carries both power and data to each device. This allows
greater flexibility in the location of network devices and significantly decreases installation
costs in many cases.
There are two system components in PoE—the Power Sourcing Equipment (PSE) initiates
the connection to the second component, and the Powered Device (PD). The current is
transmitted over two of the four twisted pairs of wires in a Category-5 cable.
Power over Ethernet (PoE) follows the IEEE 802.3af standard and is completely compatible
with existing Ethernet switches and networked devices. Because the Power Sourcing
Equipment (PSE) tests whether a networked device is PoE-capable, power is never
transmitted unless a Powered Device is at other end of the cable. It also continues to
monitor the channel. If the Powered Device does not draw a minimum current, because it
has been unplugged or physically turned off, the PSE shuts down the power to that port.
Optionally, the standard permits Powered Devices to signal to the PSEs exactly how much
power they need.
The
CWGE2FE8MSPOE Managed Switch is one of the ComWorx multi-port switches that
can be used to build high-performance switched workgroup networks. Any one of the
switches is a store-and-forward device that offers low latency for high-speed networking. It
also features a “store-and-forward “switching scheme. This allows the switch to auto-learn
and store source addresses in an 8K-entry MAC address table. The switch is targeted at
workgroup, department or backbone computing environment.