NonStop NS2200 Series Planning Guide

Also consider air conditioning failures during a real power failure because increased ambient
temperature typically causes the fans to run faster, which causes the system to draw more power.
By allowing for the maximum power consumption and applying those figures to the UPS calculations
provided in the UPS manuals, you can increase the ride-through time.
Guideline for Determining Ride-Through Time
A guideline for determining an appropriate ride-through time for your system is to use “Enclosure
Power Loads” (page 73) to calculate the maximum total rack power consumption for your system,
then find the estimated battery run time for that total using one of these documents:
• HP UPS Best Practices located at:
http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c01788957/c01788957.pdf
• HP UPS R5000 User Guide located at:
http://h10032.www1.hp.com/ctg/Manual/c02945229.pdf
• HP UPS 3 Phase User Guide located at:
http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c01079392/c01079392.pdf
The power failure time configured in SCF should be no more than 75 percent of the estimated
battery run time, converted to seconds.
Considerations for Site UPS Configurations
OSM cannot monitor a site UPS. The SCF configured ride-through time on a NonStop NS2200
system has no effect if only a site UPS is used. With a site UPS instead of a rack-mounted UPS, the
customer must perform manual system shutdown if the backup generators cannot be started.
It is also possible to have a rack-mounted UPS in addition to a site UPS. Since the site UPS can
supply a whole computer room or part of that room, including required cooling, from the perspective
of OSM, site UPS power can supply the group 100 AC power. The group 100 UPS power
configured in OSM, in this case, would still come from a rack-mounted UPS (one of the supported
models).
AC Power-Fail States
These states occur when a power failure occurs and an optional HP model R5000, R5500 XR, or
R12000/3 UPS is installed in each cabinet within the system:
DescriptionSystem State
NonStop operating system is running normally.NSK_RUNNING
OSM has detected a power failure and begins timing the outage. AC power
returning terminates RIDE_THRU and puts the operating system back into an
RIDE_THRU
NSK_RUNNING state. At the end of the predetermined RIDE_THRU time, if AC
has not returned, the system goes to POWER_OFF.
Normal halt condition. Halted processors do not participate in power-fail
handling. A normal power-on also puts the processors into the HALTED state.
HALTED
Loss of optic power from the blade element occurs, or the UPS batteries suppling
the blade elements are completely depleted. When power returns, the system
is essentially in a cold-boot condition.
POWER_OFF
AC Power-Fail States 77