Eicon Networks DIVA LAN ISDN manual Termination, Determining termination requirements

Appendix B: Technical Information Termination 161

Termination

If you are in North America or Australia and you are installing a DIVA LAN ISDN Modem with an S/T interface, you must connect the terminating resistor to ensure the proper operation of your equipment.

Determining termination requirements

Termination requirements vary depending on the number of devices connected to an external NT1 and the distance between these devices and the NT1.

Single ISDN device

If the DIVA LAN ISDN Modem is the only device connected to the external NT1, then determine the length of the cable linking the two devices.

If the cable is longer than 75 meters (250 feet):

•Connect the included terminating resistor.

•Set the NT1 to provide 100 ohms of resistance. Consult the manual provided with the NT1 for more detailed instructions.

Note Some NT1s do not support connections over 75 meters (250 feet). Check your user documentation to determine the distance supported.

If the cable is shorter than 75 meters (250 feet):

•Do not connect the included terminating resistor.

•Set the NT1 to provide 50 ohms of resistance. Consult the manual provided with the NT1 for more detailed instructions.

Multiple ISDN devices

If the NT1 is connected to more that one ISDN device, determine the length of cable connecting the DIVA LAN ISDN Modem to the NT1.

If the cable is longer than 75 meters (250 feet):

•Connect the included terminating resistor.

•Set the other ISDN devices to 100 ohms of resistance. Consult the manuals provided with these devices for more detailed instructions.

•Set the NT1 to no termination. Consult the manual provided with the NT1 for more detailed instructions.

Note Some NT1s do not support connections over 75 meters (250 feet). Check your user documentation to determine the distance supported.

If the cable is shorter than 75 meters (250 feet):

•Do not connect the included terminating resistor.

•Set the other ISDN devices to no termination. Consult the manuals provided with these devices for more detailed instructions.

•Set the NT1 to provide 50 ohms of resistance. Consult the manual provided with the NT1 for more detailed instructions.

Installing the resistor

If termination is required, install the 100 ohm terminating resistor that is included in your package as follows:

1.Insert the RJ-45 end of the ISDN cable into the resistor

TerminatingISDN

ResistorCable

2.Insert the resistor into the ISDN wall outlet.