Fuse Blown Fault - NEC Univerge SV8500 Operation And Maintenance Manual

4.9.2

Fuse Blown Fault

(1) Check the backplane of the PIR.
(a) Make a visual check on the backplane for pin contacting, melting or burn, etc.
(2) Extract all the circuit cards from the PIR, and insert them back into their slots individually to see if the fuse
blows.
(a) Set the MB switch of the PWR supply UP.
(b) Set the circuit breaker of the PWR supply DOWN.
(c) Extract all the circuit cards from their mounting slots, except PWR supply.
(d) Replace the fuse with spare.
(e) Set the circuit breaker of the PWR supply UP side.
(f) Set the MB switch of the PWR supply DOWN.
(g) Insert the circuit cards into their mounting slots individually, with their MB switch to UP side.
(h) Check to see if the fuse blows when the MB switch has been set to DOWN.
4.9.3 Circuit Breaker OFF Fault in PWR Supply
(1) Check the backplane of the PIR.
(a) Make a visual check on the backplane for pin contacting, melting or burning, etc.
(2) Extract all the circuit cards from the PIR, and make a visual check of the circuit cards.
(a) Set MB switch of the PWR supply UP.
(b) Set the circuit breaker of the PWR supply DOWN.
(c) Extract all circuit cards out of their mounting slots.
(d) Make a visual check of the extracted circuit cards. Check ICs, resistors, and capacitors to see if any
are burned.
CHAPTER 5 Operation Procedure for System with PIR
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