NEC NDA-24300 manual Trunk Faulty Situation Reference Section

FAULT REPAIR PROCEDURES

2.TRUNK FAULT

This paragraph explains the fault repair procedure when a fault, shown in Table 5-3, has occurred to a specific trunk.

Table 5-3 Trunk Fault Situation

TRUNK	FAULTY SITUATION	REFERENCE SECTION
ORT	No connection can be set up.	Section 2.3, Trunk (ORT, SND,
	PB/DP signals are erroneously received or cannot be received.	CFT) Fault
SND	No connections can be set up.
	PB/DP signals are erroneously sent out or cannot be sent out.
CFT	No connections can be set up.
	No three-way calling can be made.
	Noise gets in an established connection.
COT	No connections can be set up.	Section 2.4, Trunk (COT, TLT, DTI)
TLT	A connection results in no speech.	Fault
DTI	Noise gets in an established connection.

2.1 Check Point

When repairing a trunk fault, consider the following items:

(1)Check alarm lamps on trunk circuit cards.

(2)When an outgoing call cannot be originated to a specific trunk or when an incoming call cannot be termi- nated from a specific trunk, check Tenant Restriction Data (assigned via ATNR command) and Route Re- striction Data (assigned via ARSC command).

(3)Three-Way Conference Trunk (CFT) is on the MUX (PH-PC36) circuit cards. If a three-way conference call cannot be established, check the MUX cards.

(4)If the present timing for supervising the trunk/sender status is considered to be responsible for the fault, change the timing. The specifications for timings that can be changed with respect to trunks and senders are shown in Table 5-4and Table 5-5.

CHAPTER 5 NDA-24300

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