NEC SV8500, Operation And Maintenance Manual

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CHAPTER 5 Operation Procedure for System with PIR
(3) Extract all the line/trunk circuit cards from their mounting slots in the unit. Insert the cards back into their
slots one after another and see if the dial tone is heard each time.
(a) Extract all the line/trunk circuit cards from their slots.
Note: Set the MB switch of the line/trunk circuit card UP and extract.
(b) Confirm the MUX ACT lamp on the MUX circuit card illuminates.
(c) Set the MB switch of an extracted line/trunk circuit card UP and insert the circuit cards into their
mounting slots one by one.
(d) Confirm the OPE lamp of the inserted circuit card illuminates by setting the MB switch DOWN.
(e) Make a station-to-station call and see if DT can be heard.
[If Dial Tone (DT) is heard, check the next circuit card.]
[If DT is not heard, replace the circuit card with a spare.]
Note:
Perform this check on the rest of the circuit cards by inserting them into their individual slots.
<<For Single Configuration>>
(1) Check to see if the MUX circuit card is making poor contact.
(a) Set the MB switch of the MUX circuit card UP.
(b) Extract the MUX 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.
(c) Set the MB switch of the MUX circuit card UP and insert the circuit card into its mounting slot.
(d) Set the MB switch of the MUX circuit card DOWN.
(e) Check to see if a station-to-station connection can be set up within the faulty unit.
(2) Check by replacing the MUX circuit card with a spare.
(a) Replace the MUX circuit card referring to Section 1.5, Replacement Procedure of MUX (Multiplexer)
Circuit Card .
(b) Place the MUX circuit card into ACT mode referring to How to Control Switching Block in Chapter 2.
(c) Check to see if a station-to-station connection can be set up to identify a circuit card responsible for
the fault.
(3) Extract all the line/trunk circuit cards from their mounting slots in the unit. Insert the cards back into their
slots one after another and see if the dial tone is heard each time.
(a) Extract all the line/trunk circuit cards from their slots.
Note: Set the MB switch of the line/trunk circuit card UP and extract.
(b) Confirm the MUX ACT lamp on the MUX circuit card illuminates.
(c) Set the MB switch of an extracted Line/Trunk circuit card UP and insert the circuit cards into their
mounting slots one by one.