Z8 G4 Site Prep Guide

Input Voltage and Maximum Output Power Summary

Z8 G4 maximum power output

Input voltage <90V >90V >104V >180V

At 1125W PSU 900W 1125W 1275W 1450W

At 1450W PSU 1160W 1450W 1550W 1700W

Uninterruptible power supply (UPS)

• What is a power interruption?

A power interruption can take the form of a power failure (blackout), voltage sag, voltage surge, voltage spike, brownout

(drop), line noise, frequency variation, and switching transient and harmonic distortion.

• What is an uninterruptible power supply (UPS)?

A UPS provides power when the primary source is unavailable or insufficient. It keeps the computer powered on and

operational in the event of a power interruption.

There are three types of UPS – standby/offline, line Interactive, and online continuous. A standby/offline UPS enables the

computer to draw power from the main AC power source until there is a power interruption. It protects against power

surges, brownouts, and power failures.

A line interactive UPS protects against power problems, power failure, sags, surges, brownouts, and line noise. The

supply offers voltage regulation by bumping the mains voltage up or down. This feature improves the quality of AC power

to the supported load, reduces the number of transfers to and from battery mode, reduces the number of brief power

interruptions to the load when switching to and from battery mode, and improves battery life.

An online continuous UPS is the most dependable solution. It is also referred to as a double-conversion UPS. It provides

protection against power failures, sags, surges, brownouts, line noise, spikes, frequency variations, switching transients,

and harmonic distortion. The inverter is always on and supplies the supported load with clean, regulated power, and the

incoming power is always fully conditioned. Constant voltage and frequency regulation significantly reduce switching to

and from the battery, increasing the life and reliability of the UPS.

• How do you select a UPS?

Use a UPS for a fully loaded workstation configuration that operates in a poor power grid area. The UPS must be rated at

least 2kVA for the 1125W PSU. A UPS is necessary because without line conditioning to guarantee the minimum input

voltage the maximum output power is limited. See Power dissipation for the HP Z8 G4 Workstation on page 4 for

configurations and maximum power estimates.

HP recommends an online continuous UPS that provides a layer of insulation from quality problems. The type of supply

also allows control of output voltage and frequency regardless of input voltage and frequency. To reach the 1275W

(1125W) or 1550W (1450W) of output power, you must maintain 115V, ideally.

CAUTION! Check with your power provider to see if your facility can reliably maintain 90V power. If 90V cannot be

guaranteed to your workstation, the input voltage source might blow the fuse in the power supply or trip the breaker. For

reliable workstation operation under heavy loading, use a UPS because it provides reliable voltage levels.

• To reduce risk of a power interruption:

– Do not exceed the rated load of any single power supply (PSU). For maximum voltage/current ratings, refer to the

product’s ratings label.

– Only use the power cord included with the product.

– In general, verify that each power source circuit can safely provide the current needed for equipment that draws power

from it.