Additional maintenance procedures
DS1 CPE loopback jack (T1 only)
Maintenance Procedures
365
December 2003
Figure 111: Network Interface at “Dumb” Block with repeater line to Fiber MUX
Span Section 2 includes the short cable from the loopback jack to the “dumb” block demarcation point
(part of the loopback jack). This is the only portion of section 2 that is part of customer premises wiring
but is not covered in the loopback jack’s loopback path.
A problem can exist in one or both of the two sections. The field technician is responsible for finding and
correcting problems in Span Section 1 and the loopback cable portion of Span Section 2. The DS1 service
provider is responsible for finding and correcting problems in the majority of Span Section 2. Testing is
divided into two steps:
1
Test customer premises wiring (section 1 in
Figure 110, Network Interface at “Dumb” Block, on
) from the ICSU to the loopback jack as described in
2
Test the loopback jack-to-”dumb” block and”dumb” block-to-CO wiring (Span Section 2 in
Figure 110, Network Interface at “Dumb” Block, on page 364
). This can be done using a
loopback that “overlaps” the section of the span. Any of the following loopbacks can do this:
a
The local ICSU’s line loopback, which is typically activated, tested, and then deactivated
by the DS1 service provider at the CO end.
Figure notes
1
Span Section 1
5
Loopback Jack
2
Span Section 2
6
“Dumb” Block (Demarcation
Point)
3
120A2 (or later) Integrated Channel Service Unit
(ICSU)
7
Repeater
4
RJ-48 to Network Interface (up to 1000 Feet) (305
m)
8
Fiber MUX
9
Central Office
Summary of Contents for CMC1
Page 1: ...Maintenance Procedures 555 245 103 Issue 1 1 December 2003 ...
Page 14: ...Contents 14 Maintenance Procedures December 2003 ...
Page 416: ...Additional maintenance procedures IP Telephones 416 Maintenance Procedures December 2003 ...
Page 426: ...Index X 426 Maintenance Procedures December 2003 ...
