Allied Telesis AT-GS900/16 manual Maximum Distance

Chapter 1: Product Description

Maximum Distance

Each twisted pair port has a maximum operating distance of 100 m (328 feet).

Type of Cabling

For 10 Mbps operation, Category 3 or better 100 ohm shielded or unshielded twisted pair cabling is required. For 100 or 1000 Mbps operation, Category 5 and Enhanced Category 5 (5E) 100 ohm shielded or unshielded twisted pair cabling is required.

Auto MDI/MDI-X

All of the ports on the switch are auto-MDI and IEEE 802.3ab-compatible. Since each port's speed and duplex mode are set through Auto- Negotiation, the port uses the auto-MDI feature to automatically configure itself as MDI or MDI-X when connected to an end-node. Consequently, you can use either a straight-through or crossover twisted pair cable when connecting any network device to a port.

Green Power Saving Ports

All Ethernet ports support the power saving functions including Link-Down and Cable Length power savings. The greatest power savings occur when all 8 ports’ linked status is down and the ports are inactive. The switch uses the most power when all 8 ports are linked up to via Ethernet cables that are the maximum length or 100 meters.

When a link is not established on an individual port, the switch controller automatically reduces the power supplied to the port’s circuitry to an idle level. The greater the number of ports that are not linked up results in a greater cumulative power savings for the switch.

When a link is established on an individual port, the power provided to the PHY circuitry is based on the length of the Ethernet cable that you connect to the port. Full power is provided to the port’s circuitry if the cable length is detected to be the maximum specified cable length or 100 m. If the cable length is shorter than this, the switch senses the cable length and reduces the available port power in proportion to the detected cable length. This feature provides power efficiencies for the port even when it is actively linked to another network device.

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