IEC/TS 61934:2011(E) is applicable to the off-line electrical measurement of partial discharges (PD) that occur in electrical insulation systems (EIS) when stressed by repetitive voltage impulses generated from electronic power devices. Typical applications are EIS belonging to apparatus driven by power electronics, such as motors, inductive reactors and windmill generators. Excluded from the scope of this technical specification are: - methods based on optical or ultrasonic PD detection, - fields of application for PD measurements when stressed by non-repetitive impulse voltages such as lightning impulse or switching impulses from switchgear. The principal changes with regard to the previous edition concern the addition of: - an Introduction that provides some background information on the progress being made in the field of power electronics; - impulse generators; - PD detection methods; - a new informative Annex C covering practical experience obtained from round-robin testing (RRT); - example of noise levels, as shown in new informative Annex D.