Eicon Networks DIVA LAN ISDN - Manual (Page 161)

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
2. Insert the resistor into the ISDN wall outlet.
Terminating
Resistor
ISDN
Cable