Avaya 555-233-116 manual

Testing a loopback jack without a smart jack

Proceed as follows.

1.Test customer premises wiring from the ICSU, or from the MM710, to the loopback jack, as described in the “DS1 Span Test” section.

2.Test the loopback jack-to-dumbblock and dumb block-to-CO wiring (section 2 in Figure 30 through Figure 33). This can be done using a loopback that “overlaps” the section of the span. Any of the following loopbacks can do this:

■The local ICSU’s line loopback, which the DS1 service provider at the CO end typically activates, tests, and then deactivates.

■The local DS1 interface’s payload loopback, which the DS1 service provider at the CO end activates and tests.

■The far-end ICSU’s line loopback. Activate this test at the management terminal by entering test ds1-looplocation far-csu-loopback-test-begin, where location is the DS1 interface circuit pack corresponding to the loopback jack. Terminate this test by entering test ds1-looplocation end-loopback/span-test, where location is the DS1 interface circuit pack corresponding to the loopback jack.

Bit error counts are examined as described in the “DS1 Span Test” section. This test only isolates problems to Section 2 wiring if there are no problems in the wiring between the far-end CO and the far- end ICSU. Coordinate this test with the DS1 service provider.

Failure of any of the above tests (a, b, or c) indicate a problem in Section 2. This could mean bad loopback jack -to-”dumb” block cabling, but is more likely to indicate a problem somewhere between the “dumb” block and the CO. This is the responsibility of the DS1 service provider.

If the DS1 Span Test confirms that there are no problems in Section 1, the technician should proceed as follows to avoid unnecessary dispatch.

1.Identify and contact the DS1 service provider.

2.Inform the DS1 provider that loopback tests of the CPE wiring to the “dumb” block (section 1) showed no problems.

3.If the far-end ICSU line loopback test failed, inform the DS1 provider.

4.Request that the DS1 provider perform a loopback test of their portion of the Section 2 wiring by sending someone out to loop Section 2 back to the CO at the “dumb” block.

If this test fails, the problem is in the service provider’s wiring.

If the test passes, the problem is in the cable between the loopback jack and the “dumb” block. Replace the loopback jack.

555-233-116 Issue 4 October 2002 155