1.Safety Information
4
Measurement CAT II
applies to protect against transients from energy-consuming
equipment supplied from the fixed installation, such as TVs, PCs, portable tools, and
other household circuits.
Measurement CAT III
applies to protect against transients in equipment in fixed
equipment installations, such as distribution panels, feeders and short branch circuits,
and lighting systems in large buildings.
Measurement CAT IV
applies to measurements performed at the source of the low-
voltage installation. Examples are electricity meters and measurements on primary over
current protection devices and ripple control units.