PD IEC TS 62749:2020

This standard PD IEC TS 62749:2020 Assessment of power quality. Characteristics of electricity supplied by public networks is classified in these ICS categories:

• 17.220.99 Other standards related to electricity and magnetism

This Technical Specification specifies the expected characteristics of electricity at the point of supply of public low, medium and high voltage, 50 Hz or 60 Hz, networks, as well as power quality assessment methods.

NOTE 1 The boundaries between the various voltage levels can be different for different countries/regions. In the context of this TS, the following terms for system voltage are used:

• low voltage (LV) refers to UN ≤ 1 kV;

• medium voltage (MV) refers to 1 kV < UN ≤ 35 kV;

• high voltage (HV) refers to 35 kV < UN ≤ 230 kV.

NOTE 2 Because of existing network structures, in some countries/regions, the boundary between medium and high voltage can be different.

This document applies to the phenomena listed in Table 1.

Table 1 – Classification of electromagnetic phenomena addressed by power quality indices

Continuous phenomena	Discontinuous phenomena – Events	Other phenomena
FREQUENCY DEVIATION	SUPPLY INTERRUPTION	MAINS COMMUNICATING VOLTAGES
SUPPLY VOLTAGE DEVIATION	VOLTAGE DIP
VOLTAGE UNBALANCE	VOLTAGE SWELL
HARMONIC VOLTAGE	TRANSIENT OVERVOLTAGE
INTERHARMONIC VOLTAGE	RAPID VOLTAGE CHANGE
FLICKER （VOLTAGE FLUCTUATION)

NOTE 3 Specification of related measurement methods can be found in IEC 61000-4-30.

NOTE 4 Specification of the performance of related measuring instruments can be found in IEC 62586.

While power quality is related to EMC in a number of ways, especially because compliance with power quality requirements depends on the control of cumulative effect of electromagnetic emission from all/multiple equipment and/or installations, this document is not an EMC publication (see also Annex F).