Toshiba Strata CTX670 - Network;Csu;Rdtu Span Test

T1
Loop Back Testing
Strata CTX I&M 10/02 6-11
T1
Network/CSU/RDTU Span Test
This test checks all equipment that is checked with the test in the above paragraph, but this test
also checks that the RDTU Mitel LSI chip is functioning. Guidelines for this test are described in
Figures 6-8~6-10.
Note Loop back tests with CSU and Network equipment can also be performed when connecting
the RDTU PCB directly to a customer premise (PBX, Key Hybrid, Channel bank) T1
circuit.
The RDTU Self Test is an active test of the RDTU circuit.
The Network/CSU Test checks all cables, the Network and CSU equipment (RDTU is not active).
The Remote Loop Back (RLB) Test is an Active test of RDTU (LSI MM8976B), CSU, Network
equipment and all cables.
Refer to Figure 6-4 and the CSU manufacturer’s Installation and Maintenance manual for
information on CSU Local/Network Loopback Tests.
Figure 6-10 Network/CSU/RDTU Span Test
RDTU
RDTU TX Open
MITEL Chip
P4
MM8976B
P1/P26 Transmit
P2/P27 Receive
NDTU Cable
RDTU Amphenol Pin Nos.
Network
CSU
Network
Interface
Unit (NIU)
2581
Top LED
Bottom LED
T = About 1/2 Second
Continue to Cycle when
P4 is in ON Position
0
0
0
0
0
ON Steady
ON
OFF
OFF
OFF
OFF
ON
OFF
OFF
OFF
OFF
ON
OFF
OFF
OFF
OFF
ON
ON
OFF
OFF
OFF
Busy
FALM
FMALM
YALM
BALM
T1 T2 T3 T4 T5
0
0
ON or OFF, Steady
ON or OFF, Steady
Primary SYNC
Secondary SYNC
LEDS ON RDTU PCB
T6
1673