Installation guide

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Cisco IGX 8400 Series Installation Guide, Release 9.3.3 and Later Releases

OL-1165-06

Chapter 5 Replacing Parts on the IGX

Backplane Fuses

Backplane fuses rarely, if ever, need replacement. Backplane fuses are intended to prevent catastrophic

damage to the backplane in the event of accidental shorting of –48 VDC on the backplane to chassis

ground. This type of event could be caused by bent backplane pins, contact of conductive elements (EMI

cans, EMI gaskets, and so on) to power pins. These events would most likely happen during a factory

build or initial system installation.

Because of design constraints, these fuses need to be in sockets on the backplane and are, therefore, not

readily accessible. A special tool (Cisco P/N 218090-00) and set of instructions are required for fuse

replacement. Cisco recommends that only factory-trained personnel do the procedure.

If a bad card slot is verified, call Cisco TAC (see the “Obtaining Technical Assistance” section on

page xxiii). If a card with an open fuse is verified, return it to Cisco.

In the IGX 8410 node, backplane fuses exist only on the back of the backplane. In an IGX 8420 or

IGX 8430 node, the location of the fuse depends on the version of the backplane. In older

IGX 8420 or IGX 8430 backplanes, the fuses reside on the front. Figure 5-8 shows the location of each

fuse in an IGX 8410 backplane. The fuse numbers are F1–F8. Two spare fuses are also present.

Figure 5-9 and Figure 5-10 show current and early backplane fuse locations in the IGX 8420 backplane.

Figure 5-8 Fuse Locations, IGX 8410 Backplane

SPARE

F8 F7 F6 F5 F4 F3

5A fast blow

fuses (8 total)

System power connection

H9886