Sais Set To Dis - ADC HRU-419 HiGain User Manual

150-419-100-03>
HLU Code option is set to either AUTO or AMI. The HRU LED indicates
B8ZS if the Code option is set to B8ZS.
The AIS/ENA metallic loopback scenario includes and therefore tests all
HiGain active circuits and fully conforms with TR-TSY-000312. In this sense
it outperforms the loopback function found in most standard NID devices,
since these devices, do not include either the AIS generator or the CI T1 LOS
detector in their loopback path.
SAIS S
ET TO
This metallic loopback state is initiated in the same manner as when the ENA
option is chosen. However, once initiated, the AIS signal is not sent to the NI.
Instead the network signal is sent both towards the NI and through the relay
back towards the network. The customer's T1 transmit input port is opened
and terminated into 100 Ω. No logic loopback is required since the relay is
performing the network signal loopback function. This simple metallic
loopback state remains until a loopdown command is issued or the default
timer (if enabled) expires.
When the HRU is in its AIS/DIS SmartJack metallic loop back state, its T1
input LOS, Code and Frame monitoring circuits are connected to the
network's signal which is being looped back to these circuits through the
loopback relay.
The CPE input signal is no longer being monitored since its input circuit has
been opened and terminated into 100 Ω. The FRM and LOC LOS LEDs
indicate the status of this signal from the network. The Code LED also
indicates the code (AMI or B8ZS) of this signal if the Code option is set to
AUTO. It indicates AMI or B8ZS if the Code option is set to either AMI or
B8ZS respectively.
All of the HRU loopbacks towards the network (NREM and SMJK) are
metallic/logic (AIS/ENA) or metallic only (AIS/DIS). The SMJK and NREM
loopbacks are identical. They differ only in how they are initiated. The SMJK
identifying label indicates that the loopback was initiated by the 3- in 5-in
band command. NREM is used to indicate that the metallic loopback was
initiated by other than the 3-in 5-command (3-in 7-, 16-bit addressable
repeater commands or front panel push-button).
The HRU-419 front panel loopback (LB) button can be used to terminate any
HRU loopback (by pressing and holding the button down for five seconds).
HRU-419 List 1
DIS
September 25, 1998
Loopbacks
45