3Com DUA 1648-5AAA02 manual Spot Checks, Connecting to a Network Device, SFP Operation

Spot Checks

At frequent intervals you should visually check the Switch. Regular checks can give you an early warning of a possible failure; any problems can then be attended to when there will be least effect on users. Check the following:

Cabling	Check that all external cabling connections are secure
	and that no cables are pulled taut.
Cooling fan	Where possible, check that the cooling fan is operating
	by listening to the unit. The fan is fitted near to the
	front right hand side of the unit (when viewed from the
	front).

If you experience any problems operating the Switch, refer to “Problem Solving” on page 41.

Connecting to a Network Device

To connect a device to the Switch use Category 5 unshielded or shielded (screened) 100 Ohm TP cable (or Category 3 cable for a 10 Mbps connection). The maximum length of cable for each connection is 100 m (328 ft). Connect one end of the cable to an RJ-45 port on the Switch and the other end to the appropriate RJ-45 port on the connecting device.

3Com recommends the use of Category 5e or 6 cables for 1000BASE-T operation.

SFP Operation

The following sections describe how to insert an SFP transceiver into an SFP slot.

SFP transceivers are hot-insertable and hot-swappable. You can remove them from and insert them into any SFP port without having to power down the Switch.

Approved SFP Transceivers

The following list of approved SFP transceivers is correct at the time of publication:

■3CSFP91 SFP (SX)

■3CSFP92 SFP (LX)

To access the latest list of approved SFP transceivers for the Switch on the 3Com Corporation World Wide Web site, enter this URL into your internet browser:

http://www.3com.com

Inserting an SFP Transceiver

To be recognised as valid, the SFP transceiver must have the following characteristics:

■1000BASE-SX or 1000BASE-LX media type:

■1000BASE-SX SFP transceiver

Use this transceiver to connect the Switch directly to a multimode fiber-optic cable.

■1000BASE-LX SFP transceiver

Use this transceiver to connect the Switch directly to a single-mode fiber-optic cable or to multimode fiber using a conditioned launch cable.

If the SFP transceiver is faulty, it will not operate within the Switch. See “Problem Solving” on page 41.

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