Instruction manual

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. ”
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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 on
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 Centrex services.
Dialing Restrictions
Outgoing Call Restriction (#401) enables you to limit an extension’s dialing to
“inside calls only” (using the [
Intercom ] buttons on MLS-model 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 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 equipment restrictions apply. However, equipment dialing permissions will
not override PBX or Centrex system restrictions.
2-6 Programming