This standard PD CLC/TR 50656:2016 SPD application in conjunction with Class II equipment is classified in these ICS categories:
29.120.50 Fuses and other overcurrent protection devices
In addition to CLC/TS 61643-12, this Technical Report describes the principle of erecting SPDs to be connected to 50 Hz a.c. power circuits, rated up to 1 000 V r.m.s. in conjunction with Class II equipments.
In addition to EN 61643-11, this Technical Report gives specific guidance for SPDs intended to be installed in class II equipments.