Allied Telesis AT-8500 Series manual Minimum Power Maximum Power Class

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Chapter 1: Overview

described in Table 3. .

Table 3. IEEE 802.3af Class vs. Power Levels

 

 

Minimum Power

Maximum Power

Class

Usage

Levels Output at

Levels Output at

 

 

the PSE

the PD

 

 

 

 

 

 

 

 

0

Default

15.4W

0.44W to 12.95W

 

 

 

 

1

Optional

4.0W

0.44W to 3.84W

 

 

 

 

2

Optional

7.0W

3.84W to 6.49W

 

 

 

 

3

Optional

15.4W

6.49W to 12.95W

 

 

 

 

A port connected to a network node that is not a powered device (that is, a device that receives its power from another power source) functions as a regular Ethernet port, without PoE. The PoE feature remains enabled on the port but no power is delivered to the device.

Implementation A standard Ethernet twisted pair cable contains four pairs of strands for a total of eight strands. 10/100 Mbps network traffic requires only four strands (1, 2, 3, and 6), leaving four strands in the cable unused (4, 5, 7, and 8).

The PoE standard, IEEE 802.3af, describes two alternative ways for delivering power to a powered device (PD) over twisted pair cabling. Alternative A uses the same strands that carry the network traffic.

Alternative B uses the spare strands. The PoE implementation on the AT- 8524POE Layer 2+ Fast Ethernet Switch is Alternative A, where power is transmitted over strands 1, 2, 3, and 6.

PD’s that comply with the IEEE 802.3af standard typically support both power delivery methods. So long as a PD is compliant with the standard, it should be able to receive its power from the switch while using either a straight or cross-over cable. The PoE feature on the AT-8524POE Layer 2+ Fast Ethernet Switch should also work with most legacy PD’s as long as the device can be powered on pins 1, 2, 3, and 6. A legacy device is a node that was manufactured before the IEEE 802.3af standard was completed and, consequently, may not adhere to the standard. If this is the case, a straight (MDI) cable may be needed to insure that the DC polarity is correct.

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Contents Installation Guide Page Electrical Safety and Emissions Standards Translated Safety Statements Contents Page Figures Figures Tables Tables Preface Safety Symbols Used in this Document Symbol Meaning DescriptionWhere to Find Web-based Guides Management Software Updates Contacting Allied TelesisOverview ChapterModel Configurations Model ConfigurationModel Descriptions Port LEDs System LEDsShows 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 Port Descriptions 10/100Base-TX Twisted Pair PortsMaximum 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 and SFP Slots Gbic ModuleModule Expansion Slots LEDs Twisted Pair Port LEDs LED Mode Select ButtonState 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 Few Basics about Ethernet Switching MAC Address Table Duplex ModeStore Forward Back Pressure and Flow ControlOverview Network Topologies Power Workgroup TopologyCollapsed Backbone Topology Mixed Topology Mixed Topology Overview Installation Reviewing Safety Precautions Page Installation Selecting a Site for the Switch Maximum Planning the InstallationModel Speed Cable Type Maximum Unpacking the Switch Installing the Switch in a Rack Installation Page Installing an Optional Expansion or Stacking Module Removing the Expansion Slot FaceplateAT-A46 Installing an Optional Gbic Ferrules of the optical connector Bore Installing an Optional SFP Transceiver Page Cabling the Switch Cabling Twisted Pair PortsCabling Fiber Optic Ports SC Port Transmitter Fiber Connector Cabling Expansion Modules Powering on an AC Powered Switch Page Wiring and Powering on an DC Powered Unit Positive, Ground, and Negative Terminals8mm ±1mm 31in. ±0.039in Installation Starting a Local Management Session Installation Warranty Registration Installation PWR LED is Off Twisted Pair Port Link LED is OffFiber Optic Port Link LED is Off PoE Device is Not Receiving Power Fault LED is On ContinuouslyCannot Establish a Local Management Session Environmental Specifications Physical SpecificationsAppendix a Power Specifications Safety and Electromagnetic Emissions CertificationsPin MDI Signal SignalPin MDI Signal MDI-X Signal RJ-45 Twisted Pair Port PinoutsMDI Configuration MDI-X Configuration Pinout Pair Unused RX- and Vport-2 TX- and Vport-2AT-8516F/SC Fiber Optic Port Specifications Pin Signal RS-232 Terminal Port PinoutsRPS Connector Port Pinouts Pin Definition3V RS Pin13 3.3V RS+ Dual SC Type Connector