H

Hardware Default Voltage The rectifier output fail-safe operating voltage used if the rectifier microprocessor fails.

Hardwired Describes any equipment connected to its power source by hardware attached directly to terminal blocks or distribution panels.

Harmonic Distortion The presence of harmonics that change the AC voltage waveform from a simple sinusoidal to complex waveform. Harmonic distortion can be generated by a load and fed back to the AC utility line, causing power problems to other equipment on the same circuit.

Heterogeneous Network A network with a multitude of workstations, and operating systems, and a variety of application types from different vendors.

High Rupturing Capacity (HRC) (fuse) A precisely rated fuse which will operate under high fault current conditions, without self-destructing.

Homogeneous Network A network of components - workstation, server, operating system from the same vendor, or compatible equipment that can run under the same network or operating system.

Hot-Swappable Batteries A feature which enables the user to change UPS batteries without powering down the connected load.

Hot-Swappable Power Modules A feature which enables the user to change UPS power modules without powering down the connected load.