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www.nieaf-smitt.com
Nieaf-Smitt is a brand name of Mors Smitt
Per IEC1010 overvoltage installation category
Overvoltage category I
Equipment of OVERVOLTAGE CATEGORY I is equipment
for connection to circuits in which measures are taken
to limit the transient overvoltages to an appropriate low
level. Examples include protected electronic circuits.
Overvoltage category II
Equipment of OVERVOLTAGE CATEGORY II is energy-
consuming equipment to be supplied from the fixed
installation. Examples include household, office, and
laboratory appliances.
Overvoltage category III
Equipment of OVERVOLTAGE CATEGORY III is equipment
in fixed installations. Examples include switches in the
fixed installation and some equipment for industrial use
with permanent connection to the fixed installation.
Overvoltage category IV
Equipment of OVERVOLTAGE CATEGORY IV is for use at
the origin of the installation. Examples include electricity
meters and primary overcurrent protection equipment
