NEC SV8500, Manual

Page: 2727 / 3438

VOL.3-240
CHAPTER 2 TERMINAL-RELATED DEVICES
7.9.5 How to Proceed with Diagnostic Work from System Message
The diagnostic procedure to follow after receiving a system message is illustrated in the figure on the next
page. Decide if the fault status coincides with the indicated status, following the sequence beginning with
START.
STEP 1: Decide if the fault coincides with the fault status (1).
STEP 2: If the fault status does coincide, the fault is indicated by (2). Repair the fault according to section as
shown by (3). Otherwise, proceed to (4).
STEP 3: Perform the work indicated by (4). The result of the work (4) is broken down.
STEP 4: Decide if the result of work (4) coincides with the statuses indicated by (5).
If so, the fault is indicated either by (6) or by (2). If not, proceed to the next step.
Note:
While a fault repair is in-progress, perform various operations such as system changeover, initialization,
etc. When such operations are performed, they may affect the normally operating station lines, attendant
consoles, trunks, etc. in the form of momentary disconnection, speech interruption, 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.
The meaning of the symbol used in diagnostic work is explained below.
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.
FAULT SUPERVISION