Trotec INT BE20 Manual De Instrucciones página 15

The four overvoltage categories were specified on the ba-
sis of the following general description:
- Overvoltage category I covers appliances that are inten-
ded for connection to the permanent electrical installati-
on of a building. Measures have been taken externally to
the appliance, either in the permanent installation or bet-
ween the permanent installation and the appliance, to limit
transient overvoltages to the respective value.
- Overvoltage category II covers appliances that are inten-
ded for connection to the permanent electrical installation
of a building. Examples of such appliances are household
appliances, portable tools and similar power consumers.
- Overvoltage category III covers appliances that are part
of the permanent installation and other appliances of
which a higher degree of availability is expected.
EN
Examples of such appliances are distribution panels, pow-
er switches, distributors (IEV 826-06-01, including cables,
bus bars, distribution boxes, switches, sockets) in the per-
manent installation and appliances for industrial use, such
as stationary motors, with a constant connection to the
permanent installation.
- Overvoltage category IV covers appliances intended for
use on or near the infeed into the electrical installations
of buildings, as viewed from the main distributor towards
the grid. Examples of such appliances are electricity
meters, overcurrent protection switches and ripple con-
trol devices.
- Small air gaps can be bridged by solid parts, dust or
water.
Operating Manual – 2-pole Voltage Checker BE20 B - 2