Toshiba Strata CTX100, Installation And Maintenance Manual

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T1
Loop Back Testing
6-10
Strata CTX I&M 10/02
Loop Back Testing
The RDTU provides three loop back test configurations. These loop back tests should be
performed as required in conjunction with CSU loop back tests (see CSU loop back test
documentation).
RDTU Self Test
This test should be performed upon initial installation of a RDTU PCB. Program the RDTU per
the Strata CTX Programming Manual; then perform the RDTU loop back test, per the instructions
in
Figure 6-8 , before connecting the far end (CSU, Network, or CPE) T1 span line.
Figure 6-8 RDTU Self Test
Network/CSU T1 Span Test
This test will verify that the far end (CSU, Network, or CPE) T1 equipment and span cabling is
functioning properly. This test checks all T1 span cabling including the RDTU Amphenol cable
and connector. Guidelines for this test are provided in
Figure 6-9 .
Figure 6-9 Network/CSU T1 Span Test
RDTU Self Check
MITEL Chip
P1
Network
Interface
Unit
CSU
Remove NDTU Cable
P2
MM8976B
Network
1671
Notes
• P1 and P2 to On position (see Figure 6-2 ).
• Remove NDTU cable from RDTU amphenol connector.
• After about 12 seconds, all RDTU LEDs (except PRI/SEC SYNC) turn Off.
• Appropriate Primary or Secondary sync. LED flashes if RDTU is Primary or Secondary reference.
• If RDTU is not a Primary or Secondary reference, then the Primary and Secondary sync LEDs should
turn Off.
Network/CSU Check
Loop
Back
P1
Network
Interface
Unit
CSU
NDTU Cable
P2
On On
P26, TT
P1, TR
P27, RT
P2, RR
Network
1672
Notes
• P1 and P2 to On position (see Figure 6-2 ).
• Unplug RDTU from Strata CTX back plane.
• CSU or Network T1 equipment should receive its own transmitted signal.
• Indications and results depend on CSU and/or Network equipment.