NEC ND-71762(E) system manual END Fault Supervision, Fault Check of Work

MAINTENANCE PROCEDURE

Figure 8-2 Example of Diagnostic Work Items and Symbols

START		(1)	(2)
	When
				FAULT	: It is the fault of
		(4)				paragraph ⋅. ⋅. ⋅

(3)

Perform

(5) When

When

(4)

Perform

END

(6)
				(7)
	FAULT SUPERVISION
(2 )
	FAULT	: It is the fault of		(3 )
			paragraph ⋅. ⋅. ⋅
(2 )
	FAULT	:
			CHECK OF WORK	(8)

Note: (1): Judgment of faulty status

(2): When the fault status coincides with the indication, the cause for the fault is indicated.

(3): Operating items for diagnosis

(4): When the operating method is unknown, refer to the Operations and Maintenance Manual.

(5): Branching as the result of the operation (4)

(6): Judgment of the status as the result of the operation

(7): If, as a result of a fault diagnosis, the faulty condition cannot be reproduced and is judged to be temporary, this information is displayed.

In this case, clear the indicated alarm and the system message using the RALM command and place the system under supervision to see if the same fault recurs.

(8): While a fault repair is in progress, perform various operations such as system changeover, ini- tialization, etc. When such operations are performed, they affect the normally operating station lines, attendant consoles, trunks, etc. in the form of momentary disconnection, speech interrup- tion, forced release of calls in progress, etc.

By comparing the urgency of the required fault repair with the above-mentioned effects on the lines, trunks, etc., determine the proper timing for performing the necessary recovery work.

CHAPTER 8 ND-71762 (E)

Page 90

Issue 2