%META:TOPICINFO{author="ChrisBartram" date="1147898281" format="1.1" version="1.1"}%
%META:TOPICPARENT{name="Hp3000Hardware"}%
PowerTrust UPSes are the only UPSes the HP3000 supports w/r/t any type of automated shutdown. Many HP3000s have a dedicated (serial) port labelled for UPS on the system chasis; other systems require that you hook the UPS up via a serial port on a DTC. 

9x7 and earlier HP3000 systems had the enviable capability of being able to automatically recover from a power failure (with no data loss). These systems simply saved-state when power was lost, and upon recovery of power, reported "recovery from powerfail" and resumed exactly where they left off. This feature was removed (who knows why?) in 9x8 and all later HP3000s, making them entirely dependent on UPSes to save state, and triggering a (controlled?) system failure when UPS battery reaches critical state; which of course requires manual recovery steps (unless you have HP's additional Autorestart product).

The HP3000 communicates with the UPS via a serial connection, and when it recieves power failure indications from the UPS it will send warning messages (if configured) and finally initiate a system shutdown when the UPS determines it has reached the point of no return (i.e. power has been out long enough that there is only battery power left for an orderly system shutdown).

The HP3000 operating system understands how to communicate (only) with PowerTrust UPSes. Other brands will not work (you can get power protection from any brand, but nothing but PowerTrust UPSes can signal the HP3000 to do an orderly shutdown before the UPS batteries die).

This is a shame for several reasons... Among them the PowerTrust UPSes have no other external monitoring capability aside from colored LEDs on the front panel. If you're not checknig the front panel regularly, the batteries can die on you and you won't know until it's too late.

The PowerTrust units also have harmonics issues; UPS vendors warn about powering one UPS with power from another UPS because in some cases harmonics between the UPSes can cause one or both to fry. I can attest to this first hand as I have had multiple PowerTrusts fry because we were powering them from generator-backed-up datacenter UPSes. HP was never able to resolve the problem; the only solution was to run separate utility power lines to feed the PowerTrust UPSes directly (or not use the PowerTrust UPSes at all and power the system from the other UPSes).

On later MPE releases (6.0+) you can configure some UPS options (warning message, time till shutdown). See http://docs.hp.com/en/32650-90854/ch03s04.html --which also includes detailed guides on hooking up/configuring PowerTrust UPSes to the HP3000.


-- Main.ChrisBartram - 17 May 2006