Harmonic voltage

All harmonic measurements are performed as defined by IEC 61000-4-30.

  • Observation period of one week with fixed steps of 10 minutes.

  • N = the number of valid 10-minute intervals monitored by your meter.

  • N1 = number of intervals in which one or more of the individual harmonic levels defined in the table below are exceeded.

  • N2 = number of intervals in which the THD (total harmonic distortion) value for each voltage phase exceeds 8%. The THD calculation includes all harmonics up to the highest value the modules goes up to (40th, 50th or 63rd).

  • Ninvalid = the number of observed intervals or partial intervals that are not included in EN50160:2010 compliance calculations.

Harmonic voltage complies with the standard if N1/N ≤ 5% and N2/N ≤ 5% during the observation period.

Harmonic voltage criteria for low voltage systems

Odd harmonics

Order h Relative amplitude uh Multiple of 3
3 5.0% Yes
5 6.0% No
7 5.0% No
9 1.5% Yes
11 3.5% No
13 3.0% No
15 0.5% Yes
17 2.0% No
19 1.5% No
21 0.5% Yes
23 1.5% No
25 1.5% No

Even harmonics

Order h Relative amplitude uh
2 2.0%
4 1.0%
6....24 0.5%
NOTE: No values are given for harmonics of order higher than 25, as they are usually small, but largely unpredictable due to resonance effects.
NOTE: To configure your meter for medium or high voltage systems, configure the Harmonics Evaluation modules’ limits for medium or high harmonic voltage criteria.

EN50160 data (current observation period): the meter generates the N, N1 and N2 counts described. These counters are reset at the beginning of the next observation period.

EN50160 data (previous observation period): the meter stores the N, N1 and N2 counter values at the end of each observation period before these counters are reset. These registers are also stored in a data recorder for each observation period.

Events: the meter creates an entry in its onboard event log every time the N1 and N2 counters increases. The N1 event includes the associated harmonic.

QR code for this page

Was this helpful?