Formulary for universal measurement devices
RMS value of the current for phase conductor p
RMS value of the neutral conductor current
Effective voltage L-N
Effective voltage L-L
Neutral point voltage (vector)
Active power for phase conductor
Apparent power for phase conductor p
The apparent power is unsigned.
Total apparent power (arithmetic)
The apparent power is unsigned.
Order number of harmonics
THD
THD (Total Harmonic Distortion) refers to the distortion factor. It indicates the relationship of the harmonic components of an oscillation to the fundamental oscillation.
Distortion factor for the voltage
- M = ordinal number of harmonic
- M = 40 (UMG 604, UMG 508, UMG 96RM)
- M = 63 (UMG 605, UMG 511)
- Fundamental oscillation fund corresponds to n = 1
Distortion factor for the current
- M = ordinal number of harmonic
- M = 40 (UMG 604, UMG 508, UMG 96RM)
- M = 63 (UMG 605, UMG 511)
- Fundamental oscillation fund corresponds to n = 1
ZHD
- ZHD is the THD for the interharmonics
- It is calculated in the UMG 511 and UMG 605 device series
Interharmonics
- Interharmonics are sinusoidal oscillations whose frequency is not an integer multiple of the mains frequency (fundamental oscillation).
- It is calculated in the UMG 511 and UMG 605 device series
- Calculation and measuring methods correspond to DIN EN 61000-4-30
- The order number of an interharmonic corresponds to the order number of the next-smallest harmonic. For example, the 3rd interharmonic is between the 3rd and 4th harmonics.
TDD (I)
- TDD (Total Demand Distortion) refers to the ratio between the current harmonics (THD) and the effective current value at full load.
- IL = Full load current
- M = 40 (UMG 604, UMG 508, UMG 96RM)
- M = 63 (UMG 605, UMG 511)
Ripple control signal U (EN 61000-4-30)
The ripple control signal U is a voltage (200ms measured value) measured at a carrier frequency specified by the user. Only frequencies below 3kHz are considered.
Ripple control signal I
The ripple control signal I is a current (200ms measured value) measured at a carrier frequency specified by the user. Only frequencies below 3kHz are considered.
Positive sequence component-Negative sequence component-Zero sequence component
- The size of the voltage or current imbalance in a three-phase system is identified by the positive sequence, negative sequence, and zero sequence components.
- The symmetry of three-phase systems that is desirable during normal operation is disturbed by unbalanced loads, faults and equipment.
- Symmetry in a three-phase system is said to be present when the three phase conductor voltages and currents are equal and 120° out of phase with each other. Unbalance occurs when one or both conditions are not met. A simplified analysis of an unbalanced fault in a three-phase system is possible by calculating the symmetrical components, which are comprised of positive sequence, negative sequence, and zero sequence components.
- Unbalance is a characteristic of the power quality, for which limit values have been set according to international standards (e.g. EN 50160).
Positive sequence component
Negative sequence component
Zero sequence component
A zero sequence component can only appear if a summation current can flow back via the neutral conductor.
Voltage unbalance
Underdeviation U (EN 61000-4-30)
Underdeviation I
K-factor
The K-factor describes the increase in eddy-current losses when exposed to harmonics. If the transformer has a sinusoidal load, the K-factor = 1. The larger the K-factor, the more harmonics a transformer can be exposed to without overheating.
Power Factor (arithmetic)
The power factor is unsigned.
cos phi – Fundamental Power Factor
- Only the fundamental oscillation component is used to calculate the cos phi.
- Cos phi sign:
- - = for delivery of active power
- + = for consumption of active power
Phase angle Phi
- The phase angle between current and voltage of phase conductor p is calculated and displayed in accordance with DIN EN 61557-12.
- The sign of the phase angle corresponds to the sign of the reactive power.
Total cos phi
- Cos phi sign:
- - = for delivery of active power
- + = for consumption of active power
Fundamental oscillation-reactive power
The fundamental oscillation-reactive power is the reactive power of the fundamental oscillation and is calculated using Fourier analysis (FFT). Voltage and current do not have to be sinusoidal. All reactive power calculated in the device is fundamental oscillation-reactive power.
Sign of reactive power
- Sign Q = +1 for phi in Area 0... 180 ° (inductive)
- Sign Q = -1 for phi in Area 180... 360 ° (capacitive)
Reactive distortion power
- The reactive distortion power is the reactive power of all harmonics and is calculated using Fourier analysis (FFT).
- The apparent power S contains the fundamental oscillation und all harmonics up to the Mth harmonic.
- The active power P contains the fundamental oscillation und all harmonics up to the Mth harmonic.
- M = 40 (UMG 604, UMG 508, UMG 96RM)
- M = 63 (UMG 605, UMG 511)
Reactive power for phase conductor p
Reactive power of the fundamental oscillation
Total reactive power
Reactive power of the fundamental oscillation
Reactive energy per phase
Reactive energy per phase, inductive
Reactive energy per phase, capacitive
Reactive energy, sum L1-L3
Reactive energy, sum L1-L3, inductive
