Installation guide

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Catalyst 3750 Switch Hardware Installation Guide
OL-6336-01
Chapter 1 Product Overview
Front Panel Description
powered device first boots up in low-power mode, consumes less than 7 W, and
negotiates to obtain enough power to operate in high-power mode. The device
changes to high-power mode only when it receives confirmation from the switch.
High-power devices can operate in low-power mode on switches that do not
support power-negotiation CDP.
For information about configuring and monitoring PoE ports, see the device
manager online help and the switch software configuration guide.
Note You also can connect a Cisco IP Phone or Cisco Aironet Access Point to a Catalyst
3750 PoE switch 10/100 or 10/100/1000 port and to an AC power source for
redundant power. The powered device might switch to the AC power source as its
primary power source upon being connected to it. In that case, the PoE port
becomes the backup power source for the powered device.
If the primary source fails, the second power source becomes the primary power
source to the powered device. During the power transfer, an IP Phone might
reboot or reestablish link with the switch.
For information about Cisco IP Phones and Cisco Aironet Access Points, see the
documentation that came with your IP phone or access point.
Note 100BASE-TX and 1000BASE-T traffic requires Category 5 cable. 10BASE-T
traffic can use Category 3 or Category 4 cables.
When connecting the switch to workstations, servers, routers, and Cisco IP
Phones, be sure that the cable is a straight-through cable. When connecting the
switch to switches or hubs, use a crossover cable. When using a straight-through
or crossover cable for 1000BASE-T connections, be sure to use a twisted
four-pair, Category 5 cable for proper operation. Pinouts for the cables are
described in Appendix B, “Connector and Cable Specifications.”