Specifications

Chapter 3 Testing & Diagnostics
3-4
Yellow: The Access Bank is in a Trunk Processing state (all voice channels are
suspended) due to the T1 signal received from the network being in one of the
following alarm conditions: Loss of Signal, AIS (unframed all ones received),
or Yellow Alarm received. A Yellow Status indication may also have been set
by the Network Loopback test switch on the front of the Access Bank being
turned to the Network Loopback position, which also causes the Channel Cards
to be held in the Trunk Processing state.
Red: The Access Bank controller card has failed internally.
Off: The Access Bank power supply has failed, there is no power connected, the
ACCESS BANK 115Vac Power Supply has tripped its circuit breaker, or a
power source greater than -70Vdc is connected to the Access Bank. There are
no power fuses internal to the Access Bank. Remove power at the Access Bank
-48V Power connector to automatically reset internal solid-state protection
devices. These devices will only interrupt operation (for safety reasons) if an
excessive voltage has been applied continuously to the -48V/RET input to the
Access Bank. Check supply voltages and wiring between the power supply and
the Access Bank with a volt meter to isolate problems.
T1 Line Coding LED
Green: AMI or B8ZS Line Coding Received properly (line coding received must be the
same as configured by T1 Option Switch 5 for a Green indication)
Yellow: Bipolar Violations Received during one second intervals. A yellow flash of 1
second indicates that at least one BPV was received in error (not due to B8ZS
coding) during this second interval.
Red: Loss Of T1 Signal From The Line
Network T1 Framing LED
Green: In Frame and Frame Error Rate < 10E-5 (either ESF or D4 as configured by
T1 Option Switch 4)
Yellow: Yellow Alarm Received from Network
Red: AIS (Unframed All Ones) Received From The T1 Line
Red Flashing: Network T1 Is Out Of Frame (received signal can not be framed to ESF or D4,
as configured by T1 Option Switch 4)
Off: Framing Bit Error Rate Exceeds 10-5 (ESF or D4 framing modes)
T1 Monitor Jacks
Two Bantam type test jacks are on the front panel of the Access Bank for plugging-in T1 test equipment.
The Output Monitor Jack connects directly across the DS1 signal transmitted by the Access Bank to the
line for in-service monitoring of the Access Bank signal. The transmit pair at the Access Bank RJ-48C
(T1 Line modular jack) remains connected at pins 4 and 5 to the line. T1 test equipment plugged into this