Polycom MLC-model Telephone User Manual


 
Changing Settings to Support PBX or Centrex Services
2-11
locations, keep the same extension numbers, and retain the phones’ programmed
settings.
Changing Settings to Support
PBX or Centrex Services
This section applies only if you use PBX or Centrex services with your system. If it
does not apply, go to the next section, “System Programming Options.
PBX services are provided by a private telephone switch.
Centrex services are provided by your local telephone company from a
Central Office (CO) outside your premises. These services include the
Centrex lines connected to your control unit modules and some set of
features—such as hold, conference, or transfer—that are available on
those lines. Centrex services may be offered in your area under a different
name. For specific Centrex features to be available to you, your company
must subscribe to those features. For specific information about using
Centrex, see the Centrex documentation provided by your local telephone
company.
Some of the issues you should consider when setting up your system to work
effectively behind a PBX or Centrex system are discussed below. Chapter 5
explains how to use the programming procedures discussed here.
Recall Setting
To set up your equipment to work properly with a PBX or Centrex system, first set
Recall Timer Duration (#107) to match the setting used by your PBX or Centrex
system (usually 800 msec, or “32”). This setting affects the length of a Recall
signal sent by the control unit to access PBX or Centrex services.
Dialing Restrictions
Outgoing Call Restriction (#401) is an equipment restriction intended to limit an
extension’s dialing to “inside calls only” (using the
i buttons on system
phones) or to “inside and local calls only” (allowing calls within the PBX or Centrex
system and local calls outside the PBX or Centrex system). However, if users in
your system use a dial-out code (9 on most PBX or Centrex systems) before
dialing numbers outside the PBX or Centrex system, the equipment will not be
able to prevent toll calls for extensions restricted to “inside and local calls only”
[unless you use Disallowed Phone Number Lists (#404) to prevent dialing to
specific classes of numbers].
If your PBX or Centrex system includes dialing restrictions, use those instead of
the equipment restrictions. If you have PBX or Centrex dialing restrictions on a line
and also program equipment restrictions, both the PBX or Centrex system and