3Com MSR 20, MSR 30, MSR 50 manual Connecting interface cable of MIM-4E1/MIM-4E1-F

88CHAPTER 3: MULTIFUNCTIONAL INTERFACE MODULES

■Connect its RJ-45 connector to the RJ-45 port on the device to be connected directly, if cable extension is not needed.

■Connect its RJ-45 connector to a network interface connector and then the other end of the network interface connector to the network device to be connected through a 120-ohm E1 trunk cable, if cable extension is needed.

Figure 98 Extending an E1 120-ohm balanced twisted pair cable

DB-15

Router

	RJ-45	RJ-45Network
			devices such
			as DDN
Network interface connector

120-ohm balanced twisted pair 120-ohm E1 trunk cable

Step 4: Check the behavior of the LINK LED on the module panel. It is OFF when fault has occurred on the link and signal is out of synchronization. In this case, please check the link.

Connecting interface cable of MIM-4E1/MIM-4E1-F

Step 1: Select the appropriate 4E1 cable and E1 cable according to type of the port on the remote device, and set DIP switches of MIM-4E1 or MIM-4E1-F module correctly;

■If the resistance of the port on the device to be connected is 75-ohm, select a 75-ohm E1 non-balanced coaxial cable and a 75-ohm 4E1 conversion cable, and set all the DIP switches on the MIM-4E1/MIM-4E1-F module to “ON” (that is, the port resistance is 75-ohm).

■If the resistance of the port on the device to be connected is 120-ohm, select a 120-ohm E1 balanced twisted pair cable and a 120-ohm 4E1 conversion cable, and set all the DIP switches on the MIM-4E1/MIM-4E1-F module to “OFF” (that is, the port resistance is 120-ohm).

Step 2: Plug the DB-25 connector of the 4E1 conversion cable into a DB-25 port on MIM-4E1 or MIM-4E1-F module, and tighten the screws;

Step 3: Connect the DB-15 connector of the 4E1 conversion cable to the E1 cable, making sure of wire sequence of the connector;

Step 4: Connect the E1 cable to the device to be connected. For the procedures, see “Connecting interface cable of MIM-1E1/MIM-2E1 and MIM-1E1-F/MIM-2E1-F/MIM-4E1-F modules” on page 87.

Step 5: Check the behavior of the LINK LED on the module panel. It is OFF when fault has occurred on the link and signal is out of synchronization. In this case, please check the link.