Alarms; Tests; Maintenance - ADTRAN 1500 Installation And Maintenance Practice

13. Select T1: This option is used to select the T1 for
which performance monitoring statistics will be
displayed.
For each statistic, the following specific data is stored:
• Near End – Line: Code Violations (BVP), Errored
Seconds (ES), and Severely Errored Seconds (SES)
• Near End – Path: Code Violation (BVP), Errored
Seconds (ES), Severely Errored Seconds (SES),
Bursty Errored Seconds (BES), Severely Errored
Framing Seconds (SEFS), Controlled Slip Seconds
(CSS), and Unavailable Seconds (US)
• Far End – Path: Code Violation (BVP), Errored
Seconds (ES), Severely Errored Seconds (SES),
Bursty Errored Seconds (BES), Severely Errored
Framing Seconds (SEFS), Controlled Slip Seconds
(CSS), and Unavailable Seconds (US)
The threshold for each statistic can be independently
enabled, disabled, or have a specific value entered.
When enabled, and crossing of the threshold value will
result in a threshold entry into the Total Access 1500
Alarm Log. All thresholds are defaulted to disabled.

4. ALARMS

The Dual LIU supports an external clock input out-of-
service alarm and can be enabled or disabled. When the
alarms are enabled, an alarm condition will be created
when the external timing source is lost.

5. TESTS

The Test menu controls testing for the Dual LIU. The
Test menu allows the user to select either T1 A or B for
testing, perform local and remote loopbacks, select
which T1 to monitor, and reset the Dual LIU. The
loopbacks are described below.
Loopback Tests
The Dual LIU supports loopback tests to aid circuit
turnup and maintenance efforts. These tests are initiated
from the Total Access Site Manager or the Total Access
1500 local port on the SCU.
ADMIN
Local Loopback
T1 data is looped back toward the customer. The
transmit data is looped back after it has passed through
the framer and Dual LIU circuitry.
Line and Local Loopback
The Dual LIU supports a bi-directional loopback via
menu access only. The loopback in the network
direction will be of a line loopback type.
10
Payload Loopback
For a Payload Loopback, the T1 data is looped back
toward the network. The framing pattern, CRC6 calcu-
lation, and FDL bits are not looped back.
Line Loopback
For a Line Loopback, the T1 data is looped back toward
the network with framing and line coding unchanged.
Remote In-band Loopback
A Remote In-band Loopback initiates the transmission
of an in-band line loopback code toward the far end as
specified in ANSI T1.403.
Remote Line Loopback
A Remote Line loopback initiates the transmission of a
Facility Data Link (FDL) line loop up toward the ar end
as specified ANSI T1.403. This loopback is only
available when the Total Access 1500 is provisioned for
Extended Superframe (ESF).
Remote Payload Loopback
A Remote Payload Loopback initiates the transmission
of a FDL Payload loop up code toward the far end as
specified in ANSI T1.403. This loopback is only
available when the Total Access 1500 is provisioned for
Extended Superframe (ESF).

6. MAINTENANCE

The Dual LIU requires no routine maintenance for
normal operation.
ADTRAN does not recommend that repairs be
attempted in the field. Repair services can be obtained
by returning the defective unit to ADTRAN. Refer to
the Warranty and Customer Service
information.
Issue 4, May 2006
section for further
61180009L1-5D