Fault detection and locating 2-5
2-Mb/s Remote Peripheral Equipment Appendix 1 to 553-2741-500
Table 2-B (continued)
Fault indications and possible causes
Fa ult in dicatio n Po ssib le cause
PE2-5 LED extinguished Check for tripped PE2, PE3, PE4 or PE5
breaker on QUX20 unit.
Check for extinguished LED on a
QPC706 or QPC659 circuit pack on the
PE shelves. Replace pack with
extinguished LED.
FN LED extinguished Check FN fuse on QUX19 unit.
LED extinguished on QPC705
power converter Press the -48 V CLR button on the
QUAA3 unit.
If fault does not clear, the QPC705 or
the cable connecting it is defective.
Replace the following items until the fault
is cleared.
1) Replace the cable connecting the
QPC705.
2) Replace the QPC705.
LED extinguished on QPC706
power converter Check for tripped breaker on QUX20 unit
Check circuit packs on affected shelf by
unseating all packs, resetting the power
and reinserting packs one-at-a-time. If all
circuit packs are good, replace following
items until fault is cleared.
1) Affected QPC706 converter.
2) Power distribution cable going to shelf.
3) QUX20 unit.
