Demand test descriptions and error codes - Avaya Support

TTR-LEV (TTR Level)
MO Name Alarm Level Initial Command to Run Full Name of MO
TTR-LEV MAJ
MIN
WRN
See the Repair Procedure for TTR-LEV. TTR Level
TN748 and TN420 Tone Detector circuit packs and TN744 Call Classifier circuit packs provide
tone receivers for detecting various types of signaling tones. These circuit packs are shared
resources that serve every user of the PBX. This discussion uses the following terms and
abbreviations (note that the Maintenance-Related System-Parameters screen uses different
names than the alarm and error logs):
Type of Tone Receiver MO Also Known As Location
Dual-Tone Multifrequency
Tone Receiver
General-Purpose Tone
Detector
DTMR-PT Touch-Tone Receiver (TTR) 4 per TN420/TN748
GPTD-PT Call-Progress Tone
Receiver (CPTR)
Call Classifier CLSFY-PT Call-Classification Tone
Receiver (CCTR)
TN748s and TN420s each have 4 DTMR-PTs and 2 GPTD-PTs. DTMR-PTs interpret dual-tone
multifrequency (DTMF) calling signals and translate them into logical digits 0 through 9, *, and
#. GPTD-PTs detect call-progress tones, modem answer tones, and transmission test tones.
TN744 Call Classifier circuit packs have 8 CLSFY-PTs. These ports detect DTMF tones and
classify network and MFC (multifrequency compelled) signaling tones. (That is, CLSFY-PTs can
function as DTMR-PTs or GPTD-PTs, and have other additional capacities).
When a user goes off-hook to place a call, dial tone is returned to the user, indicating that a tone
detector is connected and ready to receive and interpret tones. The tone detector is in use until
the total number of digits needed is collected or until a time-out occurs. If every tone detector in
the system is being used simultaneously, the next user to go off-hook will not receive dial tone
until a tone detector becomes available. It is therefore necessary to have a sufficient number of
tone detectors in the system to prevent delays in receiving dial tone. The list
measurements tone-receiver command shows the level of tone detector usage.
In order to prevent dial-tone delays and other shortcomings in system performance, threshold
levels for the 3 types of tone receivers are administered on the System-Parameters
Maintenance screen. Whenever the number of tone receivers in service falls below the
administered threshold for that type of tone receiver, an alarm is logged against the TTR Level
MO. At this point, the system is operating properly, but call processing capacity is reduced.
Another alarm is logged if the number falls to zero. At this point, system operation is severely
compromised.
1018 Maintenance Alarms for Communication Manager, Media Gateways and Servers
2 per TN420/TN748
8 per TN744