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# Applications

### Inrush & TrueInrush

The Inrush current corresponds to the maximum input current drawn by an electrical device when it is powered up. This measurement helps to size the electrical installation correctly.

The Inrush is measured over a period of 10 minutes. Once the acquisition mode has been chosen (RMS or peak), the Qualistar+ captures everything. The PEAK mode can be used to view the envelopes over a period of 1 minute 20 seconds and wave forms of the inrush current captured.

### Short-term or long-term Flicker

The flicker (term specified by the IEC/EN 61000-4-15 standard) characterizes the voltage variations, which cause fluctuations in lighting, for example.

According to the applicable standards, the level of flicker is expressed by two parameters:

• The Pst or short-term flicker;

The calculation of the Pst parameter, which contributes to assessment of the flicker, is based on an algorithm of the voltage signal sampled. It is measured over a 10-minute period.

• The Plt or long-term flicker which is measured over a period of 2 hours.

### Energy values, including the Tonne Oil Equivalent

The Qualistar models can measure energy. This mode displays all the values related to power and energy.

• "Start" and "Stop" keys to trigger and halt summing of the energy values.

• New: the wide variety of units available: kW, Joule, nuclear toe, non-nuclear toe, , BTU, etc.

### Calculation of transformer K factor

Harmonic currents flowing in a network cause increased losses in the windings. This leads to heating of the transformer, thus reducing the life span of the devices connected to it.

• compliance with the NF EN 50464-3 standard for calculating transformer derating.

• the FHL and European K factor parameters are recorded and measured simultaneously.

### Harmonics

All the useful parameters are measured: THD (global and per-phase) on U, I, V, VA, phase shift of the harmonics.

Some models offer a VA harmonics function and an "expert mode".

New: the harmonics measurement function is more comprehensive:

• calculation of the harmonics in %f and %r

• decomposition of the harmonics on the neutral conductor

• calculation of the distorting voltages and currents

### Distorting power

Decomposition of the reactive power values, with the concept of non-active power (N), distorting power (D) and reactive power (Q & Q1).

• Decomposition of the reactive power to find the distorting power linked to the harmonics (VAD).

• Distorting power for sizing the harmonic filters.

• Reactive power (var) of the fundamental for sizing the battery of the power factor correction capacitor.