Functions and Screen Modes

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Functions and Screen Modes

The Tester uses a set of multipurpose screens to present each type of measurement (volts, amps, watts) as a waveform, a relational bar chart of harmonics, or a series of digital (text) readouts. With multiple values and computations on each screen, you only need to press a few keys to see everything there is to know about power (or just voltage or current) at the test point. Cycle through the choices by pressing either (or both) of these keys.

The Tester preserves selections that are active in one screen as you switch to another screen. For example, if you are measuring harmonic 7in the Volts Harmonic Screen and change function, the Tester continues measuring harmonic 7in the amps and watts harmonic screens.

Waveform Screen Mode

Volts, amps, and watts waveform screens (Figure 10) use a common format to present information about the measurement inputs. This format shows digital information on top and a waveform on the bottom. The waveform vertical scale limits usually change automatically (AUTO on) to accommodate the magnitude of the input. The horizontal scale represents 0 through 360 degrees (one cycle) of the fundamental frequency.

With a waveform screen displayed, press <or >to activate the vertical cursor bar. Continue to press these keys to position the cursor along the horizontal degree scale. A second line of digital information defines the magnitude and phase for the point where the cursor bar intersects the waveform.

Note

In the waveform screens, the frequency displayed is the frequency of the fundamental. This is normally true even when the signal being measured contains an individual harmonic with an amplitude greater than the fundamental (such as the third harmonic in the neutral current of a 3P, 4-wire system supplying non-linear loads). To obtain the frequency of a harmonic, select the harmonic screen and use <and >to position the cursor arrow under the harmonic of interest.

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Fluke 39, 41B user manual Functions and Screen Modes, Waveform Screen Mode