Testing - ADC HiGain HLU-200 User Manual

150-200-114-03, Issue 03
The green Loop LED on the HLU front panel lights whenever any of the circuit modules, HLU, HDU, or HRU,
is in a loopback state.

Testing

Tables 11 through 16 provide step-by-step test procedures for the HLU-200 List 1D as a function of the
loopback option selected. These procedures allow verification of the integrity of the HDSL channels at every
module location as well as the DS1 channels to the customer and the remote/local T1 interface.
If trouble is encountered on the HLU-200 List 1D Litespan-2000 Interface, verify that the HLU-200 List 1D is
making a positive connection to the CBA backplane.
Upstream
loopbacks
toward
Litespan
backplane
* The SmartJack loopback is a metallic loopback in the HRU list 6,7, and 8.
It is a logic loopback in all HRU of lists 1-5.
** Set the SAIS option to ENA to send the AIS pattern to the CI during
SmartJack loopback.
Figure 7. HLU-200 List 1D Non-Doubler GNLB Loopback Configurations
HLU-200 List 1D
HLU-200 HDSL
HLU-200 HDSL
HLU-200
HDSL
HLU-200
4 -in- 7 HDSL
NLOC
HLU-200
AIS
6 -in- 7 HDSL
CREM
AIS
HLU-200
HDSL
November 22, 1996
HRU-412
AIS
LOGIC
TLOS
HRU-412
AIS
3 -in- 7
NREM
HRU-412
AIS**
2 -in- 5
SMJK*
CI
AIS
HRU-412
HRU-412
Downstream
loopbacks
HRU-412
5-in-7
CLOC
toward
customer
1150
25