NEC SV8500 Operation And Maintenance Manual - page 704
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CHAPTER 5
Operation Procedure for System with PIR
4.13 Integrated Service Digital Network (ISDN) Line Fault
This section explains the fault repair procedure when any of the faults shown in Table 5-11 occur to a spe-
cific ISDN.
Table 5-11 ISDN Line Fault Situation
4.13.1 Check Point
When repairing an ISDN Line fault, consider the following items:
(1) Check the alarm lamps on the DCH or PRT circuit card.
(2) Refer to Figure 5-28, and check the cable connection.
4.13.2 ISDN Line Control
The DCH/PRT circuit card controls the signal link (digital) of the ISDN line and transmits/receives call
processing information.
The signal link controls permit normal transmission and reception of call processing information. Figure
5-28 shows the ISDN line control route.
Figure 5-28 Controlling ISDN Line
FAULTY SITUATION
REFERENCE SECTION
A specific CCH/CCT card is faulty.
Section 4.13.3, Specific DCH/PRT Card Is Faulty
When the signal transmission line is a digital line, transmitting/
receiving of control signals cannot be performed.
Section 4.13.4, Fault of DCH, DTI, and Related Flat
MUX
DCH
PRT
DTI
LT Cable
Front
Cable
MDF
To ISDN Line
LT Cable