ps1_fault_sensor scsi id

[icahn]

After installing a Store Edge DDS4 external tape drive into a brand-new out of the box v280r running Solaris 8, I'm getting this in /var/adm/messages:

[ID 961923 daemon.error] WARNING: Device PS1 failure detected by sensor PS1_FAULT_SENSOR

Any ideas what's causing this?

Also, the scsi id at the back of the tape drive shows "4"; how can I confirm that it's using scsi address 4? From prtconf, all the likely entries have "driver not attached" except for these:
scsi, instance #0
... etc ...
sd, instance #6
... etc ...
scsi, instance #1
... etc ...
st, instance #11

Does this mean that something is using scsi address 11 on scsi adapter 1? Perhaps cdrom on #6 and dds4 on #11? What's sd and st?

(The tape drive seems to work fine)

TIA

 

[icahn]

The fault_sensor message went away after second power supply was connected (machine is dual fed).