This part of IEC 60947 applies to control and protective switching devices (or equipment)
(CPS), the main contacts of which are intended to be connected to circuits of rated voltage not
exceeding 1 000 V a.c. or 1 500 V d.c.
CPSs are intended to provide both protective and control functions for circuits and are
operated otherwise than by hand. They may also fulfill additional functions, such as isolation.
Digital inputs and/or digital outputs contained in CPSs, and intended to be compatible with
PLCs are covered by IEC 61131-2.