Rptu Loop-Back Test - Toshiba STRATA CTX100 Installation And Maintenance Manual

## BUU LOOP BACK TEST ##
SLOT=ss CIRCUIT=m B1:OK B2:OK D:OK
The above response indicates the test was passed and that the B1, B2 and D channels and the
wire connections for the tested device are operating properly.
If the Strata CTX responds with:
TEST FAIL
The test failure could be caused by:
• U-terminal is in busy state when the test was started.
• U-terminal is in TQ/ACB/ACD mode when the test was started
• The Strata CTX BRI PCB slot or circuit number was not entered correctly.
• U-terminal can not support loop back testing U-terminal, BRI PCB, or wiring is defective.
If The Strata CTX responds with:
TEST EXIT
Test exit could be caused by:
• The Strata CTX processor did not get test results from the BRI circuit within 5 second from
start of the test.
• U-terminal or BRI circuit was unplugged during the test.
• User made the exit request during testing

RPTU Loop-back Test

The RPTU has loop-back test jumpers that enable physical connections (cables/jacks/plugs)
between the RPTU, CSU, and the network PRI line to be tested (see
that the CSU receives and transmits the PRI signal properly in both directions. The test signals,
generated by the Network PRI provider, pass through the CSU and loop around the RPTU. The
RPTU sends the received test signal back through the CSU to the Network and the Network
detector checks for a valid signal.
CO ISDN
ISDN PRI
PRI Test
Signal
Network
Jack
RJ48C
or RJ48X
Demarcation Point
Figure 5-28 Loop-back Test
Strata CTX I&M 10/02
ISDN PRI
CSU
(RJ45)
ISDN Testing and Troubleshooting
Figure 5-28). The tests check
RPTU
JP1
(LB-ON)
1.5MHz
line
Interface
LSI
JP2
(LB-ON)
ISDN Interfaces
2756
5-31