Replacing a TX Matrix Fiber-Optic Array Cable

1. Removing a TX Matrix Fiber-Optic Array Cable
2. Installing a TX Matrix Fiber-Optic Array Cable

Removing a TX Matrix Fiber-Optic Array Cable

Note: If you have previously routed a spare fiber-optic array cable between the TX Matrix router and T640 router, some of the steps in this procedure have already been performed.

To remove a fiber-optic array cable:

1. Bring the interface connected by the fiber-optic array cable offline using one of the following methods:
   • Issue the following CLI command:
     user@host> request chassis sib slot slot-number lcc lcc-number offline

     The slot number can be from 0 through 4 and corresponds to the TX-SIB chassis slot. The LCC number can be 0 through 3 and corresponds to the TX-SIB adapters labeled LCC0 through LCC3.

   • Press and hold the online/offline button next to the TX-SIB adapter until the RX LED is not lit.
   • Press and hold the online/offline button on the T640-SIB faceplate until the RX LED is not lit.
2. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
3. Remove the fiber-optic array cable connectors from the TX-SIB and T640-SIB. To remove a cable connector, partially loosen the thumbscrew and captive screw on the fiber-optic array cable connector. (Use the supplied small slotted screwdriver to loosen the captive screw.) Alternate between the thumbscrew and captive screw until the cable connector is removed from the adapter.
4. Install a dust cover on each of the two removed cable connectors. Align the dust cover with the cable connector and carefully press them together until they stop. The cover and the cable connector are keyed to ensure proper mating. Secure the dust cover by tightening the thumbscrew and captive screw on the connector. (Use the supplied small slotted screwdriver to tighten the captive screw.)
5. Remove the fiber-optic array cable. If the cable is greater than 10 m long, we recommend that you reinstall the pulling-eye assembly on one end of the cable to facilitate pulling the cable through the raceway.

Installing a TX Matrix Fiber-Optic Array Cable

Caution: While you install the TX Matrix router or replace a fiber-optic array cable, small deposits of oil, dust, and debris can enter the TX-SIB and T640-SIB fiber-optic array adapters, the fiber-optic array cable connectors, and the loopback connectors and adapters. We recommend that you clean the optics in these components, as well as the loopback connector and adapter dust covers, immediately before connecting them. For cleaning instructions, see Cleaning the TX Matrix and T640 Fiber-Optic Components Overview.

1. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
2. Using the supplied label sheets, attach a label to each end of the replacement fiber-optic array cable to help you identify the corresponding TX-SIB adapter and T640-SIB. The labels are marked with the chassis ID and the switching plane (separated with a slash). For example, use the label marked 0/2 to identify a connection between adapter LCC0 on TX-SIB-2 and T640-SIB-2 in router LCC0. Fiber-Optic Array Cable Connections between TX-SIBs and T640-SIBs lists the connections between TX-SIBs and T640-SIBs.

   Note: You must use the same length for every fiber-optic array cable from a particular T640 router to the TX Matrix router. However, you do not need to use the same length for all fiber-optic array cables within a routing matrix.

3. Route the end of the fiber-optic array cable that plugs into the TX-SIB over the TX Matrix router to the TX-SIB adapter. If you have installed the optional cable shelf assembly, use the lowest shelf to support a cable destined to any TX-SIB adapter labeled LCC0, use the next shelf up to support a cable destined to any TX-SIB adapter labeled LCC1, and so on (see Fiber-Optic Array Cable Routing Through Cable Management System).

   Note: If you have previously routed a spare fiber-optic array cable between the TX Matrix router and T640 router, some of the steps in this procedure have already been performed.

   Caution: You must maintain a minimum bend radius of 2 in. (5.1 cm). We recommend that you maintain a bend radius of 10 in. (25.4 cm). If you must bend a fiber-optic array cable to a 2-inch radius, we recommend that you do not use more than two such bends.

   Caution: Plastic wrap-ties can damage or crimp the fiber-optic array cables (see Figure 1). We recommend that you use soft band straps to secure fiber-optic array cables. Figure 1: Using Soft Band Straps to Secure Fiber-Optic Array Cables

4. Grasp the metal cover on the comb within the comb panel assembly that extends over the TX-SIB you will be connecting. Firmly pull the cover away from the chassis until it is removed from the comb (see Removing a Comb Cover on the Comb Panel Assembly).
5. While aligning the fiber-optic array cable connector with its corresponding TX-SIB adapter, route the cable upward along the comb tooth, and press it into the tooth. Use the tooth closest to the chassis to support a cable destined to any TX-SIB adapter labeled LCC0, use the next tooth away from the chassis to support a cable destined to any TX-SIB adapter labeled LCC1, and so on (see Fiber-Optic Array Cable Routing Through Cable Management System).
6. Reinstall the metal cover on the comb by firmly pressing it toward the chassis until it stops.
7. Route the other end of the fiber-optic array cable to the T640-SIB adapter.
8. Dress the fiber-optic array cable so it does not interfere with system airflow and maintenance access (see Figure 2).

   Figure 2: Maintaining a Minimum Bend Radius of 10 in. (25.4 cm)

   

   For an illustration of airflow through the TX Matrix router and the T640 router, see Airflow Through the Chassis and the T640 Core Router Hardware Guide .

9. Remove the dust covers from the fiber-optic array cable connectors. Loosen the thumbscrew and captive screw on each connector. (Use the supplied small slotted screwdriver to loosen the captive screw.) Store the dust covers in a dust-free resealable plastic bag.
10. Align the fiber-optic array cable connector with the corresponding TX-SIB adapter and carefully press it into the adapter until it stops. The cable connector and adapter are keyed to ensure proper mating.

    Note: The optics in a fiber-optic array adapter are spring loaded, so you must continue to apply force to a fiber-optic array cable connector or loopback connector while securing it to a TX-SIB or T640-SIB adapter.

    Warning: Do not look directly into a fiber-optic array adapter or a connector at the end of a fiber-optic array cable attached to an adapter. The fiber optics emit laser light that can damage your eyes.

11. Partially tighten the thumbscrew and captive screw on the fiber-optic array cable connector. (Use the supplied small slotted screwdriver to tighten the captive screw.) Alternate between the thumbscrew and captive screw until the cable connector is secured to the adapter.
12. With the fiber-optic array cable extending toward the left side of the chassis (as you face the rear), align the cable connector with the T640-SIB adapter and carefully press it into the adapter until it stops. The cable connector and adapter are keyed to ensure proper mating.
13. Repeat Step 11 for the fiber-optic array cable connector plugged into the T640-SIB adapter.
14. Bring the interface connected by the fiber-optic array cable online using one of the following methods:
    • Issue the following CLI command:
      user@host> request chassis sib slot slot-number lcc lcc-number online 

      The slot number can be from 0 through 4 and corresponds to the TX-SIB chassis slot. The LCC number can be 0 through 3 and corresponds to the TX-SIB adapters labeled LCC0 through LCC3.

    • Press and hold the online/offline button next to the TX-SIB adapter until the RX LED begins blinking.
    • Press and hold the online/offline button on the T640-SIB faceplate until the RX LED begins blinking.

    If both the TX and RX LEDs next to the TX-SIB adapter and T640-SIB adapter do not steadily light green, look at the display on the craft interface to check the status of the TX-SIB. TX-SIB LEDs describes the functions of these LEDs.