Allied Telesis AT-8500 Series manual Power Over Ethernet

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AT-8500 Series Layer 2+ Fast Ethernet Switches Installation Guide

Power Over Ethernet

The following discussion applies only to the AT-8524POE switch.

The twisted pair ports on the AT-8524POE switch feature Power over Ethernet (PoE). PoE is a mechanism for supplying power to network devices over the same twisted pair cables used to carry network traffic. This feature can simplify network installation and maintenance by allowing you to use the switch as a central power source for other network devices.

A device that receives its power over an Ethernet cable is called a powered device. Examples of such devices can be wireless access points, IP telephones, web cams, and even other Ethernet switches. A powered device connected to a port on the switch will receive both network traffic and power over the same twisted pair cable.

There are several advantages that the PoE feature of the AT-8524POE switch adds to the installation and maintenance of your network. First, because the switch acts as the central power source for your powered devices, adding an uninterruptible power source (UPS) to the switch increases the protection not just to the switch itself from possible power source problems but also to all of the powered devices connected to it. This can increase the reliability of your network by minimizing the impact to network operations from a power failure.

PoE can also simplify the installation of your network. A frequent issue in selecting a location for a network device is whether there is a power source nearby. This often limits equipment placement or requires the added cost and time of having additional electrical sources installed. With PoE, you can install PoE-compatible network equipment wherever they are needed without having to worry about whether they are near a power source.

The switch automatically determines whether or not a device connected to a port is a powered device. A powered device has a signature resistor or signature capacitor that the switch can detect over the Ethernet cabling. If the resistor or capacitor is present, the switch assumes that the device is a powered device.

Power Budgeting The AT-8524POE Layer 2+ Fast Ethernet Switch provides a maximum of

15.4W of power per port on all 24 ports for a total power consumption of 370 W, while at the same time furnishing standard 10/100 Mbps Ethernet functionality.

The AT-8524POE smart power management functionality supports any combination of Ethernet ports (1-24) that supply power for IEEE 802.3af Class 0, 1, 2, or 3 powered devices up to a maximum of 370 watts, as

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Contents Installation Guide Page Electrical Safety and Emissions Standards Translated Safety Statements Contents Page Figures Figures Tables Tables Preface Symbol Meaning Description Safety Symbols Used in this DocumentWhere to Find Web-based Guides Contacting Allied Telesis Management Software UpdatesChapter OverviewModel Configuration Model ConfigurationsPort LEDs System LEDs Model DescriptionsShows the front and back panels of the AT-8524M switch Shows the front and back panels of the AT-8524POE switch Shows the front and back panels of the AT-8550GB switch AT-8550SP Switch Front and Back Panels 10/100Base-TX Twisted Pair Ports Port DescriptionsMaximum Distance 10/100/ 1000Base-T Twisted Pair Ports 100Base-FX Fiber Optic Ports Type of Cable Power Over Ethernet Minimum Power Maximum Power Class Gbic Module Gbic and SFP SlotsModule Expansion Slots Twisted Pair Port LEDs LED Mode Select Button LEDsState Description Mode FDX OFF Indicates that the port is operating at 10 or Fiber Optic Port LEDs Gbic and SFP Expansion Slot LEDs Maste RS-232 Terminal Port Power Options and Connectors AC Power Connector DC Power Connector MAC Address Table Duplex Mode Few Basics about Ethernet SwitchingBack Pressure and Flow Control Store ForwardOverview Power Workgroup Topology Network TopologiesCollapsed Backbone Topology Mixed Topology Mixed Topology Overview Installation Reviewing Safety Precautions Page Installation Selecting a Site for the Switch Planning the Installation MaximumModel Speed Cable Type Maximum Unpacking the Switch Installing the Switch in a Rack Installation Page Removing the Expansion Slot Faceplate Installing an Optional Expansion or Stacking ModuleAT-A46 Installing an Optional Gbic Ferrules of the optical connector Bore Installing an Optional SFP Transceiver Page Cabling Twisted Pair Ports Cabling the SwitchCabling Fiber Optic Ports SC Port Transmitter Fiber Connector Cabling Expansion Modules Powering on an AC Powered Switch Page Positive, Ground, and Negative Terminals Wiring and Powering on an DC Powered Unit8mm ±1mm 31in. ±0.039in Installation Starting a Local Management Session Installation Warranty Registration Installation Twisted Pair Port Link LED is Off PWR LED is OffFiber Optic Port Link LED is Off Fault LED is On Continuously PoE Device is Not Receiving PowerCannot Establish a Local Management Session Physical Specifications Environmental SpecificationsAppendix a Safety and Electromagnetic Emissions Certifications Power SpecificationsRJ-45 Twisted Pair Port Pinouts Pin MDI SignalSignal Pin MDI Signal MDI-X SignalUnused RX- and Vport-2 TX- and Vport-2 MDI Configuration MDI-X Configuration Pinout PairAT-8516F/SC Fiber Optic Port Specifications RS-232 Terminal Port Pinouts Pin SignalPin Definition RPS Connector Port PinoutsPin 3V RS13 3.3V RS+ Dual SC Type Connector