Measurement for Grid power quality

Some regulations or specific contracts require energy providers to keep voltage characteristics at any supply terminal within specified limits. These specifications cover limits or values related to voltage, frequency, rapid voltage changes, harmonics, interharmonics, unbalance, dips, swells, interruptions, flicker, ….

Measurements are typically made on the energy provider side (to check delivered energy complies to the contract) and on the consumer side (to check received energy complies with the contract) with Power Quality Instruments class A according to IEC 61000-4-30.

Fig. S7 – Standards for Grid power quality assessment

Application assessment standard	Measuring methods standard	Product standard
EN 50160 Voltage characteristics of electricity supplied by public electricity networks	IEC 61000-4-30 class A Testing and measuring techniques – Power quality measurement methods	PQI (Power Quality Instruments) IEC 62586-1 Power quality measurement in power supply systems - Power Quality Instruments (PQI) and IEC 62586-2 Power quality measurement in power supply systems - Functional tests and uncertainty requirements (Compliance to IEC 62586-2 means compliance to IEC 61000-4-30)
IEC/TS 62749 Assessment of Power Quality – Characteristics of electricity supplied by public electricity networks