Install the TDU1

Electrostatic Discharge (ESD)

Observe and follow all ESD instructions while handling Tellabs plug-in equipment.

Caution! The Tellabs plug-in equipment uses semiconductor devices that can be damaged by electrostatic discharge (ESD). Do not remove a plug-in from a protective packing box or equipment rack until the time of installation or replacement. To equalize the static charge on the plug-in, establish a body path to the ground using an ESD wrist strap connected to an ESD ground. [If storing or shipping the plug-in becomes necessary, place the plug-in in a conductive shipping box to prevent static buildup.]

Apply the following precautions:

• Use grounded wrist straps, table mats, floor mats
• Handle static-sensitive devices in the nonconductive areas
• Place static-sensitive cards into an antistatic plastic bag    
• Use protective ESD-sensitive packing and shipping bags when returning repairable components

Note: Installation of the TDU1 is only required for the MDS5 shelf.

When the Timing Distribution Units (TDUs) are installed in the MDS5 OLT, the MDS5 can be configured as a:

• Timing Server
• Timing Client

In the server configuration, primary and secondary composite clock (CC) inputs are connected to the TDU (CC A and CC B, respectively) inputs. The TDU digitizes the analog composite clock timing signal. The digitized signal is then transported across the backplane to all of the input/output (I/O) slots in the MDS5. The TDU can then be provisioned, in the Tellabs 1191 Element Management System (EMS) and can support up to thirty-two (32) Remote Terminal (RT) Internet Protocol (IP) addresses (refer to Managing the Tellabs 1100 Series Optical LAN User’s Guide, Configure the Timing Server and Clients).

The TDU, via the ESU in the COT Timing Server, then transports the composite clock timing signal, to those RTs configured as clients in the EMS, using Timing over Packet (ToP) protocol.

The timing server can also be wired to support local timing clients.

In the RT configuration, if the RT is located in physical proximity to the COT or RT Timing Server, the composite clock signal can be wired to RT Timing Clients, in a daisy-chain configuration, from the TDUs in the Timing Server MDS5 shelf.

Note: In this configuration, the RT Timing Clients, using the daisy-chained composite clock signal, do not require an EMS provisioned connection to a timing server.

Use the following procedure to install the redundant TDUs.

1. If not already open, open the MDS5 cover.
2. Remove the blank faceplates from the slots labeled TDU A and TDU B.
3. Unpack and inspect the TDUs for any apparent damage. If there is apparent damage, notify the supervisor for assistance and do not proceed (see Figure 1).

Figure 1: Timing Distribution Unit (TDU1)

4. Insert the primary TDU into the upper and lower card guides of the slot labeled TDU A until the card contacts the backplane connector. Then apply equal pressure on both upper and lower ejectors to seat the TDU.
5. Upon insertion, the STAT LED illuminates RED while performing internal power-up diagnostics. Upon successful completion of the power up diagnostics, the STAT LED blinks GREEN at 0.5-second intervals while initializing. Upon completion of initialization, the STAT LED illuminates solid GREEN (see Figure ).

Figure 2: MDS5 with ESUs and TDUs

6. Did the STAT LED sequence as described in Step 5?
   • If YES, go to Step 7.
   • If NO, remove the card and replace it with a known good unit.
7. Repeat Step 3 through Step 6 and install the secondary TDU in the slot labeled TDU B.

8. Run two pairs of 24-26 gauge CAT5 shielded twisted pair wire from the TSG distribution to the vicinity of the TDU A CC A and CC B connectors (see Figure 3).

   Note: It is not necessary to loosen the connector mounting screws. These screws secure the connectors to the faceplate.

Figure 3: TDU Composite Clock Connector

9. Using a small screwdriver, loosen the two wire terminating screws on each of the CC A and CC B connectors on both TDUs (see Figure 3).
    

   Note: There are three possible timing circuit wiring configurations.

• Figure 4 shows the wiring for a MDS5 COT or RT timing server.
• Figure 5 shows the wiring for a MDS5 RT timing server.

10. Locate the 100MHz ferrite core and wrap it around the shielded twisted pair timing cable.

    Note: The ferrite core should be attached to the twisted pair timing cable as close as possible to the shield breakout (see Figure 19).

11. Separate the shield ground from the twisted-pair cable.
12. Using a Phillips screw driver, loosen the shield ground screw on the faceplate of TDU A.
13. Place the shield ground under the head of the shield ground screw and tighten (see Figure 4).
14. Connect one pair of 24-26 gauge shielded twisted pair from the TSG output distribution to the CC A and CC B connectors on TDU A (see Figure 4).

Figure 4: MDS5 COT Timing Server or RT Timing Client Input Wiring

15. Using the same wire size and type, connect a jumper from the CC A and CC B connectors of TDU A to the CC A and CC B connectors of TDU B (see Figure 4).
16. Connect a 133-Ohm termination resistor to the CC A and CC B terminals of TDU B.
17. If timing is to be distributed to multiple shelves in an area where there is no timing distribution available, such as in a cabinet, the outputs of one shelf can be daisy-chained to the inputs of another shelf, as shown in Figure 5,

    Note: This configuration would be used when the customer wants to save on Internet Protocol (IP) addresses at the Tellabs 1191 EMS Timing Server configuration. The EMS timing server configuration is limited to thirty-two (32) IP addresses.

Figure 5: MDS5 Timing Output Wiring

18. Tighten the screws on each connector to secure the composite clock connections and terminating resistors (see Figure 18).
19. Notify the Data Center/Network Operations Center (NOC) that the TDU has been installed and is ready to be provisioned (refer to Managing the Tellabs 1100 Series Optical LAN User’s Guide, Configure the Timing Server and Clients).
20. Is this MDS5 to be configured as a Central Office Terminal (COT)?
    • If YES, the EXT TIM LED on the TDUs illuminate as soon as a valid timing source is detected.
    • If NO, the EXT TIM LED on the TDUs illuminate after approximately 3 to 6 minutes while the TDUs achieve synchronization with the configured timing server.