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
|Order h||Relative amplitude uh||Multiple of 3|
|Order h||Relative amplitude uh|
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.