user manual

ND-20292
CHAPTER 5
APRIL, 1990
Intermittent Ring Problems
I
Check memory block 16 to
ensure line is programmed to
ring on an existing station
No No
v v
Program ring Program ring
Assignment and Assignment and
test test
Run the following tests:
1. Measure CO ring voltage
with AC meter (100 vat
2OHz) at the MDF.
2. Perform a second
initialization.
3. Place an external ringer in
front of the system on a
worst case CO line. Find
out if the customer can
hearthe external ringer at
times when the system
does not detect ringing on
this line.
4.
Replace TSW-E and
test. If problem is not
solved, perform 1 st
initialization, replace CPU-
E ( ). Test system using
default program.
11
End
I
Testto see if problem
occurs on all Multiline
Terminals assigned ringing
a:. AlI
Terminals
7
Replace at least one Multiline
1 Terminal whicihas problems. 1
and deny the DND feature.
v+ No+7
Check tosee if lines
affected can be isolated
to one COLE ETU
Check to see if lines
affected can be isolated
to one module
Reset COI-E( ) ETU and test.
Replace COI-E( ) ETU
Reset MMC-E ETU and test.
Replace MMC-E ETU.
Reset TSW-E ETU and test.
Replace TSW-E ETU.
1 .
.
./
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