Chapter 2: Site Preparation
Perle 833IS User Guide 19
Telephony Cabling
The connection to the ISDN network is made via an RJ-45 connector. The 833IS is
shipped with the appropriate cables required to connect to the telephone network.
These cables are standard UTP cables.
The carrier brings the ISDN BRI service to a "Demarcation Point" (also known as
Demark or Demarc), and assumes responsibility for wiring and equipment up to the
Demarc. You are responsible for the wiring from the Demarc to the 833IS.
Depending on the carrier, the Demarc may either be brought to the 833IS or it may
terminate some considerable distance from the unit. You will need to work with the
carrier in advance to determine where the ISDN BRI service will be brought, and if
necessary, arrange for the wiring from the Demarc to the 833IS.
S/T Termination A BRI S/T interface requires line termination. Some telcos require that this 100-ohm
termination be provided within the customer equipment. Check with your telco to
see if it is necessary for the 833IS to provide this termination.
An improperly terminated BRI line may cause line errors on the BRI line. This
would typically be seen as a dial in client abnormally losing connection.
The 833IS ships with termination enabled. Termination is enabled or disabled by
using jumpers on the System Card and (if installed) Expansion Card. There is one
pair of jumpers for each interface:
■JP250 - BRI 1
■JP350 - BRI 2
■JP450 - BRI 3
■JP550 - BRI 4
! UTP Cable