Ufer ground.
Name after the man who invented and tested it, a Ufer ground is a grounding electrode consisting of at least 20 feet (6 m) of 1/2-inch (13 mm) rebar (either a continuous single bar or shorter lengths tied-wired together) or of at least 20 feet of wire-size 4 AWG or larger copper wire embedded in a concrete footing or piling.
Ungrounded.
An electrical power distribution system that is not connected to earth ground or to a conductive body that extends the ground connection.
Uninterruptible Power Supply (UPS).
A self-contained, battery backed-up regulated power supply.
