Power Quality Logger
Glossary
45
Glossary
[1] Requires IEEE 519/Report License.
Unbalance (u2)
Supply Voltage Unbalance
Condition in a three phase system in which the RMS values of the line-to-line voltages (fundamental component), or the phase angles between
consecutive line voltages, are not all equal. The unbalance value is the ratio of the negative sequence to the positive sequence in percent and is
typically in the range between 0 % and 2 %.
h01 [V, A]
Fundamental Frequency Component
RMS value of the fundamental frequency component of voltage or current. Sub grouping according to IEC 61000-4-7 is applied.
h02 … h50 [%]
Harmonic component of voltage or current.
The ratio of the RMS value of the voltage or current harmonic components h02 … h50 to the RMS value of the fundamental component h01 of
voltage or current. Depending on the selected harmonics calculation method, Sub grouping, grouping or harmonic component is applied according
to IEC 61000-4-7.
THD [%]
Total Harmonic Distortion
The ratio of the RMS value of the sum of all the voltage or current harmonic components h02 … h50 to the RMS value of the fundamental
component h01 of voltage or current.
THC [V, A]
Total Harmonic Content
The RMS value of the sum of all the voltage or current harmonic components h02 … h50.
ih01 … ih50 [%]
Interharmonic component of voltage or current. The ratio of the RMS value of the voltage or current interharmonic components ih01… ih50 to the
RMS value of the fundamental component h01 of voltage or current. Depending on the selected harmonics calculation method, Sub grouping or
harmonic component is applied according to IEC 61000-4-7.
TID [%]
Total Interharmonic Distortion
The ratio of the RMS value of the sum of all voltage or current interharmonic components ih01 … ih50 to the RMS value of the fundamental
component h01 of voltage or current. Depending on the selected harmonics calculation method, Sub grouping or harmonic component is
applied according to IEC 61000-4-7.
TIC [V, A]
Total Interharmonic Content
The RMS value of the sum of all the voltage or current interharmonic components ih02 … ih50.
TDD
[1]
[%]
Total Demand Distortion
The ratio of the RMS value of the sum of all the current harmonic components h02 … h50 to I
L
, the maximum demand current.
I
L
[1]
[A]
Maximum Demand Load Current
The current value is established at the point of common coupling and should be taken as the sum of the currents corresponding to the maximum
demand during each of the twelve previous months divided by 12.
This value is required to calculate TDD and to determine the applicable current harmonic limits defined by IEEE 519. This value is a user input in
the measurement configuration.
I
SC
[1]
[A]
Maximum Short Circuit Current at Point of Common Coupling
This value is required to determine the applicable current harmonic limits defined by IEEE 519. This value is a user input in the measurement
configuration.
P
ST
, P
LT
PST is the short term flicker value calculated over defined 10-minute periods. PLT is the long term flicker calculated over defined 2-hour periods.
SSID
Service Set Identifier (WiFi) - name of the access point or the name of a hidden SSID
