Instruction manual

Features
Centrex service supports only touch-tone telephones,
With Full Centrex, the Recall and fixed function buttons (Conference,
Transfer, and Drop) control Centrex functions. Corresponding communications
system functions can be programmed on buttons if any are available. (See
Recall/Timed Flash for additional information.) With Limited Centrex, the Recall
and fixed function buttons control communications system functions. In either
case, some Centrex functions can be programmed on Directory and Auto Dial
buttons, but not on other blank feature buttons.
During high-traffic periods, the loop-start lines used by Centrex can cause a
glare problem when multiple calls access the same line simultaneously. Loop-
start lines also have higher cable losses than ground-start lines, and cannot
guarantee secure toll restriction.
With Limited Centrex, in either Key or Hybrid/PBX mode, DID, TIE, WATS, and
T1 lines can be used. They cannot be used with Full Centrex in Behind Switch
mode.
With Limited Centrex, outside calls made by using an SA button to access a
pool require two access codes for outside calls, one access code for the pool,
and one for outside lines on the Centrex.
Centrex users should not be assigned Calling Restrictions because the system
prevents a telephone with Calling Restrictions from sending a switchhook flash
to the CO. Calling restrictions should be placed at the Centrex.
Once a call connection is made with Centrex service, the system cannot detect
additional calls that are initiated following a Centrex switchhook flash. Therefore,
the SMDR and systems such as CAS, Integrated Solution II (IS-II), Integrated
Solution III (IS-III), and CAT do not report the additional calls.
Users who have access to both Centrex and communications system features
must be aware of which they are connected to when they attempt to use a
feature. Use of Centrex buttons when connected to the communications system,
or of communications system buttons when connected to Centrex Service will
cause misdialed calls.
If an MFM is not being used on an MLX telephone, the second extension should
be removed in order to reduce the number of Centrex lines. The automatic
assignment of two extensions to each MLX set may mean the installer must
renumber the system because the removed numbers are not automatically
reassigned, and because their removal leaves empty places in the sequential
numbering of extensions. See System Numbering for additional information.
88 Centrex Operation