NEC Neax 2400 Ipx System Operations And Maintenance Manual

							NDA-24307 CHAPTER 5
Page 403
Issue 1
FAULT REPAIR PROCEDURES
(2) For Single Configuration
Check to see if the fault occurs by
replacing TSW circuit cards one by one.Replace the TSW circuit card referring to
Section 2.3.2, TSW Card Replacement
Procedure, Chapter 4.
Check to see if a station-to-station connection
can be set up and identify a TSW circuit card
responsible for the fault.
Perform the above check by extracting the TSW
circuit cards individually.
Check to see if the fault occurs by
replacing MUX circuit cards one by one.Replace the MUX circuit card referring to
Section 3.3.2, MUX Card Replacement
Procedure, Chapter 4.
Initialize the system by pressing the START
button on the TOPU.
Check to see if a station-to-station connection
can be set up and identify a TSW circuit card
responsible for the fault.
Perform the above check by extracting the TSW
circuit cards individually.
ATTENTIONContents
Static Sensitive
Handling
Precautions Required
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							CHAPTER 5 NDA-24307
Page 404
Issue 1
FAULT REPAIR PROCEDURES
When the PLO (PH-CK16-A/17-A)/CLK
(PH-CK18) circuit card is mounted for
digital interface, replace the PLO circuit
card with a spare and check it.Set MB switch of the PLO/CLK circuit card
to UP side.
Confirm OPE lamp on the PLO/CLK circuit
card goes out.
Extract PLO/CLK circuit card from its
mounting slot.
Set MB switch UP and insert the new PLO/
CLK circuit card into its mounting slot.
Set MB switch DOWN.
Confirm the OPE lamp on the new PLO/CLK
circuit card illuminates.
Confirm that speech can be carried out
normally by a station-to-station call.
ATTENTIONContents
Static Sensitive
Handling
Precautions Required
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							NDA-24307 CHAPTER 5
Page 405
Issue 1
FAULT REPAIR PROCEDURES
5.3 Speech Path System Fault - When Dial Tone (DT) Cannot Be Heard
Faulty Situation:
Dial Tone (DT) cannot be heard.
[1-A] Both TSW Failure (Permanent)
[1-E] Both TSW Clock Failure
[4-C] Both TSW Ready Failure
[23-Y] MUX Clock Failure
Note:For dual system configuration, if a system message indicates that both systems are faulty, first repair
the fault in the indicated system and then proceed to repair the PIM in the other system.
Check to see if the TSW circuit card is
making poor contact.Set TSW circuit card into STBY mode. Refer to
Section 12, Chapter 6.
Set TSW MBR switch on the TSW card UP.
Set MB switch of the TSW circuit card UP.
Extract the TSW circuit card from its mounting
slot and clean the contact portion.
If cleaning cannot be done, repeat insertion and
extraction of the circuit card two or three times.
Set TSW MBR and MB switches on the TSW
circuit card UP and insert the circuit card into
its mounting slot.
Set MB switch of the TSW circuit card DOWN.
Set TSW MBR switch DOWN.
Check if a station-to-station connection can be
set up.
Check PCM cables. Check the PCM cables. (See Figure 5-8).
Initialize the system by pressing the START
button on the TOPU and see if a station-to-sta-
tion connection can be set up.
ATTENTIONContents
Static Sensitive
Handling
Precautions Required
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							CHAPTER 5 NDA-24307
Page 406
Issue 1
FAULT REPAIR PROCEDURES
5.4 Speech Path System Fault (LN) - STBY Side Has Become Faulty
Faulty Situation:
A fault occurred in the STBY side of the dual configuration system.
[1-B] TSW Failure (Permanent)
[1-D] TSW Write Failure
[1-F] TSW Clock Failure
[4-D] TSW Ready Failure
Check to see if the TSW circuit card
(STBY) is making poor contact.Set the TSW MBR switch of the TSW circuit
card UP.
Set the MB switch of the TSW circuit card UP
and extract the circuit card from its mounting
slot.
Extract the TSW circuit card from its mounting
slot and clean the contact portion.
If cleaning cannot be done, repeat insertion and
extraction of the circuit card two or three times.
Set the TSW MBR and MB switches of the
TSW circuit card UP and insert the circuit card
into its mounting slot.
Set the MB switch of the TSW circuit card
DOWN.
Set the TSW MBR switch DOWN.
Check if a station-to-station connection can be
set up.
Check PCM cables. Check the PCM cables. See Figure 5-8.
Initialize the system by pressing the START
button on the TOPU and see if a station-to-
station connection can be set up.
ATTENTIONContents
Static Sensitive
Handling
Precautions Required
START
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							NDA-24307 CHAPTER 5
Page 407
Issue 1
FAULT REPAIR PROCEDURES
Faulty Situation:
Fault related to speech such as noise, one-way speech, no-speed, etc. occurs.
Even if dialing started, Dial Tone (DT) does not stop.
[1-C] Both TSW Write Failure
[1-D] TSW Write Failure
Check to see if fault occurs by extracting
TSW circuit cards one by one.Replace the TSW circuit card referring to
Section 2.3.2, TSW Card Replacement
Procedure, Chapter 4.
Set the TSW circuit card into ACT mode. Refer
to Section 12, Chapter 6.
Check to see if a station-to-station connection
can be set up to identify a TSW circuit card re-
sponsible for the fault.
Perform the above check by extracting the TSW
circuit cards individually.
Check to see if the fault occurs by
extracting MUX circuit cards one by one.Replace the MUX circuit card referring to
Section 3.3.2, MUX Card Replacement
Procedure, Chapter 4.
Set the MUX circuit card into ACT mode. Refer
to Perform the above check by extracting the
TSW circuit cards individually.
Check to see if a station-to-station connection
can be set up and identify a TSW circuit card
responsible for the fault.
Perform the above check by extracting the
MUX circuit cards individually.
ATTENTIONContents
Static Sensitive
Handling
Precautions Required
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							CHAPTER 5 NDA-24307
Page 408
Issue 1
FAULT REPAIR PROCEDURES
6. SPEECH PATH SYSTEM FAULT (WHOLE SYSTEM/ISW)
This section explains the fault repair procedure when any of the fault shown in Table 5-8 has occurred in a
whole system.
6.1 Check Point
System messages pertaining to whole system fault are shown in Figure 5-9. Check the system messages.
Figure 5-9   System Messages Related to Speech Path System Fault (Whole System/ISW)Table 5-8  Speech Path (TSW) System Fault Situation (LN)
FAULTY SITUATION REFERENCE SECTION
Noise, one-way speech, no tone
Even after dialing a digit, dial tone is still heard.
Dial tone cannot be heard.Section 6.2, Speech Path System Fault (Whole 
System/ISW) - Fault Related to Speech
The system message that indicates a fault occurrence to the active 
Speech Path System (Whole System /ISW) is intermittently printed 
out.
The alarm lamp on the circuit card of the active Speech Path System 
(Whole System /ISW) lights up intermittently.Section 6.3, Speech Path System Fault (Whole 
System/ISW) - ACT side becomes Faulty 
Intermittently
The system message that indicates a fault occurrence to the STBY 
Speech Path System (Whole System /ISW) is intermittently printed 
out.
The alarm lamp on the circuit card of the STBY Speech Path 
System (Whole System /ISW) lights up intermittently.Section 6.4, Speech Path System Fault (Whole 
System/ISW) - STBY side becomes Faulty 
Intermittently
Clock (CALK, PLOT) is faulty.
CPUTSW
PLO/CLK
HSW
“1-G” ~ “1-J”HSW Write Failure
“1-K” ~ “1-L”HSW Clock Failure
“4-E” ~ “4-F”HSW Ready Failure
“1-A” ~ “1-D”TSW Write Failure
“1-E” ~ “1-F”TSW Clock Failure
“4-C” ~ “4-D”TSW Ready Failure
“1-O” ~ “1-P”PLO Clock Failure 
						

							NDA-24307 CHAPTER 5
Page 409
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FAULT REPAIR PROCEDURES
6.2 Speech Path System Fault (Whole System/ISW) - Fault Related to Speech
Replace the TSW card mounted in the 
ISWM with a spare.Replace the TSW card by referring to Section 
4.3.2, TSW Card Replacement Procedure, 
Chapter 4.
Place the TSW circuit card on the ACT mode.
Refer to Section 12, Chapter 6.
After replacement of the TSW card, 
make a station to station call and 
check and see if a fault occurs.
When a fault occurs in the whole system, 
replace the HSW card with a spare.Replace the HSW card by referring to Section 
4.3.3, HSW Card Replacement Procedure, 
Chapter 4.
Place the HSW card on the ACT mode. 
Refer to Section 12, Chapter 6.
After replacement of the HSW card, 
make a station to station call, and 
check and see if a fault occurs.
AT T E N T I O NContents
Static Sensitive
Handling
Precautions Required
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							CHAPTER 5 NDA-24307
Page 410
Issue 1
FAULT REPAIR PROCEDURES
6.3 Speech Path System Fault (Whole System/ISW) - ACT side becomes Faulty 
Intermittently
Check by replacing related circuit cards of 
the ACT mode with a spare.Related circuit cards: 
IOGT (Section 4.3.1, Chapter 4)
TSW (Section 4.3.2, Chapter 4)
HSW (Section 4.3.3, Chapter 4)
Set the faulty system on the STBY mode.
Refer to Section 12, Chapter 6.
On the circuit card, set its MB switch UP and 
extract the circuit card out of its mounting slot.
Make switch setting on the new circuit card.
On the new circuit card, set its MB switch UP 
and insert the circuit card into its mounting slot.
Set MB switch DOWN.
If a fault occurs, set the faulty system on the 
STBY mode. Refer to Section 12, Chapter 
6.Set the faulty system on the ACT mode.
Refer to Section 12, Chapter 6.
Check and see if a fault indication is made. Faulty Situation:
ACT-side Speech Path System becomes faulty intermittently in ISW/Whole System.
[1-I] HSW Write Temporary Failure (Both Systems)
[1-J] HSW Write Temporary Failure (One System)
ATTENTIONContents
Static Sensitive
Handling
Precautions Required
START
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							NDA-24307 CHAPTER 5
Page 411
Issue 1
FAULT REPAIR PROCEDURES
6.4 Speech Path System Fault (Whole System/ISW) - STBY side becomes Faulty 
Intermittently
Check by replacing related circuit cards of 
the STBYmode with a spare.Related circuit cards: 
IOGT (Section 4.3.1, Chapter 4)
TSW (Section 4.3.2, Chapter 4)
HSW (Section 4.3.3, Chapter 4)
Set the faulty system on the STBY mode.
Refer to Section 12, Chapter 6.
On the circuit card, set its MB switch UP and 
extract the circuit card out of its mounting slot.
Make switch setting on the new circuit card.
On the new circuit card, set its MB switch UP 
and insert the circuit card into its mounting slot.
Set MB switch DOWN.
If a fault occurs, set the faulty system on the 
STBY mode. Refer to Section 12, Chapter 
6.Set the faulty system on the ACT mode.
Refer to Section 12, Chapter 6.
Check and see if a fault indication is made. Faulty Situation:
STBY-side Speech Path System becomes faulty intermittently in ISW/Whole System.
[1-I] HSW Write Temporary Failure (Both Systems)
ATTENTIONContents
Static Sensitive
Handling
Precautions Required
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							CHAPTER 5 NDA-24307
Page 412
Issue 1
FAULT REPAIR PROCEDURES
6.5 PLO Fault
Replace the faulty PLO circuit card with a 
spare.Set MB switch of the PLO circuit card UP and 
extract the circuit card from its mounting slot.
Make necessary switch settings on the new PLO 
circuit card.
Set MB switch UP and insert the circuit card 
into its mounting slot.
Set MB switch DOWN.
Confirm that no noise generates in a station- 
to-station connection.If the system has been operated by the STBY 
side, set MB switch on the ACT-side PLO 
circuit card UP and execute system changeover.
Refer to Section 12, Chapter 6.
OPE lamp (Green) illuminates on the PLO 
circuit card.
Confirm that digital interface connection can 
be set up. Faulty Situation:
Both PLOs have become faulty, and the system is in operation by clocks from the
HSW.
One of the two PLOs has become faulty and the other PLO has been set on the ACT
mode.
[1-O], [1-P] PLO Clock Failure
[1-K], [1-L] HSW Clock Failure
ATTENTIONContents
Static Sensitive
Handling
Precautions Required
START
END