DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126 Issue 4
June 1999
Maintenance Object Repair Procedures
9-1814TTR-LEV (TTR Level)
9
When a user goes off-hook to place a c all, dial tone is returned to the user,
indicating that a tone d etector is connec ted and ready to receive and interpret
tones. The tone detector is in use until the total numb er of digits needed is
collected or until a time-ou t occurs. If all tone detec tors in the system are being
used simultaneously, the next user to go off-hook will not receiv e dial tone until a
tone detector bec omes available. It is therefore necessar y to have a sufficient
number of tone detectors in the system to prevent delays in receivin g dial tone.
The list measurements tone-receiver c ommand shows the level of tone
detector usage. For more information on this command, refer to the following
documents:
■

DEFINITY Enterprise Communications Server Release 5.4 Administration

and Feature Description
■

DEFINITY Communications System Generic 3 V2 Traffic Reports,

555-230-511
In order to prevent dial-tone d elays and other shortcoming s in system
performance, threshold levels for the 3 types of tone receivers are administered
on the change system-parameters maintenance form. Whenever the number of
tone receivers in service falls below the ad ministered threshold for that typ e of
tone receiver, an alarm is logg ed against the TTR Level maintenance objec t. At
this point, the system is operating properly, but call proc essing capac ity is
reduced. Another alarm is log ged if the number fall s to zero. At this point, system
operation is severely compromised .
Typical causes of these events are:
1. The threshold for GPTD-PTs or DTMR-PTs is administered incorrectly on
the maintenance-related system p arameters form.
2. Too many GPTD-PTs, DTMR-PTs, or CLSFY-PTs have been taken out of
service, possibly b y maintenance software or a demand busyout.
3. A tone detector circ uit pack has been removed or suffered a fatal failure,
resulting in the loss of all its por ts.
4. The system has an insufficient number of TN748/TN744/TN420 circuit
packs.
Repair Procedure for TTR-LEV
To resolve a TTR-LEV alarm:
1. Display errors and use the TTR-LEV Error Log Table to determine which
type of tone receiver has fallen bel ow its threshold.
2. Enter change system-parameters maintenance, and check the
administered value. On the form, TTR represents DTMR-PTs, CPTR
represents GPTD-PTs, and Call Classifier represents CLSFY-PTs. If the
threshold value is set too high, c hange it to a lower value and wait a
minute for the alarm to clear.