Internet Router Hardware Guide

Replacing Hardware Components
2. A tt ach an electrostatic discharge (ESD) grounding strap to your bare wrist and
connect the strap to one of the ESD points on the chassis. Make sure t he router
is attached to a proper earth ground. For more information about ESD, see
“Preventing Electrostatic Discharge Damage” on page 226.
3. Label the cable connected to the SFP so that you can later reconnect it
to the correct SFP.
4. Disconnect the cable from the SFP. Immediately cov er the transceiver and the
end of the cable with a rubber safety cap.
WARNING: Do not look directly into the ends of fiber-optic cables or into the
transceivers on the interface faceplate. Single-mode fiber-optic cable and the
interfaces that use it (such as ATM and SONET/SDH interfaces) emit laser light
that can damage your eyes.
CAUTION: Do not leave a fiber-optic transceiver uncovered except when inserting
or removing cable. The safety cap keeps the port clean and prevents accidental
exposure to laser light.
5. Arrange the cable in the cable management system to prevent it from
dislodging or developing stress points. Secure the cable so that it is not
supporting its own weight as it hangs to the floor. Place excess cable out of the
way in a neatly coiled loop in the cable management system. Placing fasteners
on the loop helps to maintain its shape.
CAUTION: Avoid bending fiber-optic cable beyond its minimum bend radius. An arc
smaller than a few inches in diameter can damage the cable and cause problems
that are difficult to diagnose.
6. Pull the ejector handle away from the SFP faceplate to unseat the SFP from
the PIC. Pull the SFP out of the PIC and place it on the antistatic mat or in
the electrostatic bag.
Installing an SFP
To install a replacement SFP, follow t his procedure (see Figure 98):
1. A tt ach an electrostatic discharge (ESD) grounding strap to your bare wrist and
connect the strap to one of the ESD points on the chassis. Make sure t he router
Replacing Packet Forwarding Engine Components 191