75
isnotconsideredOVcategoryIV.
• category III applies to equipment permanently connected in fixed
installations(downstreamof,andincluding,themaindistribution board).Examplesare
switchgearandotherequipmentinanindustrialinstallation;
• category II applies to equipment not permanently connected to the fixed
installation.Examples are appliances, portable tools and other pl
ug‐connected
equipment;
• category I applies to equipment connected to a circuit where measures have
beentakentoreducetransientovervoltagestoalowlevel.