3Com SUPERSTACK 3 3870 Series Getting Started Manual page 28

28 C 2: I
HAPTER NSTALLING THE
S
WITCH
Use this transceiver to connect the Switch directly to a single-mode
fiber-optic cable or to multimode fiber using a conditioned launch
cable.
1000BASE-LH70 SFP transceiver
■
Use this transceiver to connect the Switch directly to a single-mode
fiber-optic cable.
If the SFP transceiver is faulty, it will not operate within the Switch. See
"Solving Hardware Problems"
3Com recommends that you only use SFPs supplied by 3Com. If the SFP
transceiver is invalid it will not be recognized by the Switch.
Use the following sequence of steps to activate the SFP ports:
1 The SFP transceiver is keyed and there is only one way in which it can be
installed correctly. It is not necessary to power-down your Switch.
2 Hold the transceiver so that the connector is toward you and the product
label is visible. Ensure the wire release lever is closed (in the upright
position).
3 Gently slide the transceiver into the SFP port until it clicks. If the
transceiver does not click into place, remove it, turn it over and re-insert.
4 Remove the plastic protective cover if fitted.
CAUTION: The dual personality ports on the Switch 3870 enable you to
activate an RJ-45 port or an SFP port or a mixture of both (for example,on
the 24 Port Switch, you can activate the RJ-45 ports 21 and 22 and the
SFP ports 23 and 24 at the same time). If you try to activate the same dual
personality RJ-45 port and SFP port (for example, RJ-45 port 23 and SFP
port 23 at the same time), the SFP port will take priority.
on page 49.