Note

An open fuse condition can be alsobe determined from the scsipba

 

diagnostic.

 

If another device on the SCSIbus provides termination power, the bus

 

can continue to operate normally.

Before replacing the TERMPWR fuse,identify the reasonfor the failure. Check for sonrces of short circuits on the SCSI buscables and connectors. Check for proper mating of contact pins on the SCSIbus cables. Be sure that power is off on the host computer and peripheral deviceswhen connecting SCSIbus cablesto prevent inadvertent shorting.

To remove and replace the fuse, proceed as follows:

1. Remove the card from the hostcomputer asdescribed previously in this chapter.

2As shown in figure 2-3, pull the fuse out of its socket. It is usually a good idea to verify that the fuseis open by using a continuity tester.

3.To install the replacement fuse,carefully align the two contact pins with the socket holes. Then simply pressthe fusein. The fusehas no polarity, so the pins cango into either sockethole.

Wiggle fuse ollghlly whllr pulling lt

Flgure 2-3. Replacing the TERMPWR Fuse

Service Information 2-13

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HP 28642A manual Diagnostic, Can continue to operate normally, Flgure 2-3. Replacing the Termpwr Fuse Service Information